Fixed bug #64830 mimetype detection segfaults on mp3 file

private int
mget(struct magic_set *ms, const unsigned char *s, struct magic *m,
    size_t nbytes, size_t o, unsigned int cont_level, int mode, int text,
    int flip, int recursion_level, int *printed_something,
    int *need_separator, int *returnval)
{
	uint32_t soffset, offset = ms->offset;
	uint32_t count = m->str_range;
	int rv, oneed_separator;
	char *sbuf, *rbuf;
	union VALUETYPE *p = &ms->ms_value;
	struct mlist ml;

	if (recursion_level >= 20) {
		file_error(ms, 0, "recursion nesting exceeded");
		return -1;
	}

	if (mcopy(ms, p, m->type, m->flag & INDIR, s, (uint32_t)(offset + o),
	    (uint32_t)nbytes, count) == -1)
		return -1;

	if ((ms->flags & MAGIC_DEBUG) != 0) {
		fprintf(stderr, "mget(type=%d, flag=%x, offset=%u, o=%zu, "
		    "nbytes=%zu, count=%u)\n", m->type, m->flag, offset, o,
		    nbytes, count);
		mdebug(offset, (char *)(void *)p, sizeof(union VALUETYPE));
	}

	if (m->flag & INDIR) {
		int off = m->in_offset;
		if (m->in_op & FILE_OPINDIRECT) {
			const union VALUETYPE *q = CAST(const union VALUETYPE *,
			    ((const void *)(s + offset + off)));
			switch (cvt_flip(m->in_type, flip)) {
			case FILE_BYTE:
				off = q->b;
				break;
			case FILE_SHORT:
				off = q->h;
				break;
			case FILE_BESHORT:
				off = (short)((q->hs[0]<<8)|(q->hs[1]));
				break;
			case FILE_LESHORT:
				off = (short)((q->hs[1]<<8)|(q->hs[0]));
				break;
			case FILE_LONG:
				off = q->l;
				break;
			case FILE_BELONG:
			case FILE_BEID3:
				off = (int32_t)((q->hl[0]<<24)|(q->hl[1]<<16)|
						 (q->hl[2]<<8)|(q->hl[3]));
				break;
			case FILE_LEID3:
			case FILE_LELONG:
				off = (int32_t)((q->hl[3]<<24)|(q->hl[2]<<16)|
						 (q->hl[1]<<8)|(q->hl[0]));
				break;
			case FILE_MELONG:
				off = (int32_t)((q->hl[1]<<24)|(q->hl[0]<<16)|
						 (q->hl[3]<<8)|(q->hl[2]));
				break;
			}
			if ((ms->flags & MAGIC_DEBUG) != 0)
				fprintf(stderr, "indirect offs=%u\n", off);
		}
		switch (cvt_flip(m->in_type, flip)) {
		case FILE_BYTE:
			if (nbytes < (offset + 1))
				return 0;
			if (off) {
				switch (m->in_op & FILE_OPS_MASK) {
				case FILE_OPAND:
					offset = p->b & off;
					break;
				case FILE_OPOR:
					offset = p->b | off;
					break;
				case FILE_OPXOR:
					offset = p->b ^ off;
					break;
				case FILE_OPADD:
					offset = p->b + off;
					break;
				case FILE_OPMINUS:
					offset = p->b - off;
					break;
				case FILE_OPMULTIPLY:
					offset = p->b * off;
					break;
				case FILE_OPDIVIDE:
					offset = p->b / off;
					break;
				case FILE_OPMODULO:
					offset = p->b % off;
					break;
				}
			} else
				offset = p->b;
			if (m->in_op & FILE_OPINVERSE)
				offset = ~offset;
			break;
		case FILE_BESHORT:
			if (nbytes < (offset + 2))
				return 0;
			if (off) {
				switch (m->in_op & FILE_OPS_MASK) {
				case FILE_OPAND:
					offset = (short)((p->hs[0]<<8)|
							 (p->hs[1])) &
						 off;
					break;
				case FILE_OPOR:
					offset = (short)((p->hs[0]<<8)|
							 (p->hs[1])) |
						 off;
					break;
				case FILE_OPXOR:
					offset = (short)((p->hs[0]<<8)|
							 (p->hs[1])) ^
						 off;
					break;
				case FILE_OPADD:
					offset = (short)((p->hs[0]<<8)|
							 (p->hs[1])) +
						 off;
					break;
				case FILE_OPMINUS:
					offset = (short)((p->hs[0]<<8)|
							 (p->hs[1])) -
						 off;
					break;
				case FILE_OPMULTIPLY:
					offset = (short)((p->hs[0]<<8)|
							 (p->hs[1])) *
						 off;
					break;
				case FILE_OPDIVIDE:
					offset = (short)((p->hs[0]<<8)|
							 (p->hs[1])) /
						 off;
					break;
				case FILE_OPMODULO:
					offset = (short)((p->hs[0]<<8)|
							 (p->hs[1])) %
						 off;
					break;
				}
			} else
				offset = (short)((p->hs[0]<<8)|
						 (p->hs[1]));
			if (m->in_op & FILE_OPINVERSE)
				offset = ~offset;
			break;
		case FILE_LESHORT:
			if (nbytes < (offset + 2))
				return 0;
			if (off) {
				switch (m->in_op & FILE_OPS_MASK) {
				case FILE_OPAND:
					offset = (short)((p->hs[1]<<8)|
							 (p->hs[0])) &
						 off;
					break;
				case FILE_OPOR:
					offset = (short)((p->hs[1]<<8)|
							 (p->hs[0])) |
						 off;
					break;
				case FILE_OPXOR:
					offset = (short)((p->hs[1]<<8)|
							 (p->hs[0])) ^
						 off;
					break;
				case FILE_OPADD:
					offset = (short)((p->hs[1]<<8)|
							 (p->hs[0])) +
						 off;
					break;
				case FILE_OPMINUS:
					offset = (short)((p->hs[1]<<8)|
							 (p->hs[0])) -
						 off;
					break;
				case FILE_OPMULTIPLY:
					offset = (short)((p->hs[1]<<8)|
							 (p->hs[0])) *
						 off;
					break;
				case FILE_OPDIVIDE:
					offset = (short)((p->hs[1]<<8)|
							 (p->hs[0])) /
						 off;
					break;
				case FILE_OPMODULO:
					offset = (short)((p->hs[1]<<8)|
							 (p->hs[0])) %
						 off;
					break;
				}
			} else
				offset = (short)((p->hs[1]<<8)|
						 (p->hs[0]));
			if (m->in_op & FILE_OPINVERSE)
				offset = ~offset;
			break;
		case FILE_SHORT:
			if (nbytes < (offset + 2))
				return 0;
			if (off) {
				switch (m->in_op & FILE_OPS_MASK) {
				case FILE_OPAND:
					offset = p->h & off;
					break;
				case FILE_OPOR:
					offset = p->h | off;
					break;
				case FILE_OPXOR:
					offset = p->h ^ off;
					break;
				case FILE_OPADD:
					offset = p->h + off;
					break;
				case FILE_OPMINUS:
					offset = p->h - off;
					break;
				case FILE_OPMULTIPLY:
					offset = p->h * off;
					break;
				case FILE_OPDIVIDE:
					offset = p->h / off;
					break;
				case FILE_OPMODULO:
					offset = p->h % off;
					break;
				}
			}
			else
				offset = p->h;
			if (m->in_op & FILE_OPINVERSE)
				offset = ~offset;
			break;
		case FILE_BELONG:
		case FILE_BEID3:
			if (nbytes < (offset + 4))
				return 0;
			if (off) {
				switch (m->in_op & FILE_OPS_MASK) {
				case FILE_OPAND:
					offset = (int32_t)((p->hl[0]<<24)|
							 (p->hl[1]<<16)|
							 (p->hl[2]<<8)|
							 (p->hl[3])) &
						 off;
					break;
				case FILE_OPOR:
					offset = (int32_t)((p->hl[0]<<24)|
							 (p->hl[1]<<16)|
							 (p->hl[2]<<8)|
							 (p->hl[3])) |
						 off;
					break;
				case FILE_OPXOR:
					offset = (int32_t)((p->hl[0]<<24)|
							 (p->hl[1]<<16)|
							 (p->hl[2]<<8)|
							 (p->hl[3])) ^
						 off;
					break;
				case FILE_OPADD:
					offset = (int32_t)((p->hl[0]<<24)|
							 (p->hl[1]<<16)|
							 (p->hl[2]<<8)|
							 (p->hl[3])) +
						 off;
					break;
				case FILE_OPMINUS:
					offset = (int32_t)((p->hl[0]<<24)|
							 (p->hl[1]<<16)|
							 (p->hl[2]<<8)|
							 (p->hl[3])) -
						 off;
					break;
				case FILE_OPMULTIPLY:
					offset = (int32_t)((p->hl[0]<<24)|
							 (p->hl[1]<<16)|
							 (p->hl[2]<<8)|
							 (p->hl[3])) *
						 off;
					break;
				case FILE_OPDIVIDE:
					offset = (int32_t)((p->hl[0]<<24)|
							 (p->hl[1]<<16)|
							 (p->hl[2]<<8)|
							 (p->hl[3])) /
						 off;
					break;
				case FILE_OPMODULO:
					offset = (int32_t)((p->hl[0]<<24)|
							 (p->hl[1]<<16)|
							 (p->hl[2]<<8)|
							 (p->hl[3])) %
						 off;
					break;
				}
			} else
				offset = (int32_t)((p->hl[0]<<24)|
						 (p->hl[1]<<16)|
						 (p->hl[2]<<8)|
						 (p->hl[3]));
			if (m->in_op & FILE_OPINVERSE)
				offset = ~offset;
			break;
		case FILE_LELONG:
		case FILE_LEID3:
			if (nbytes < (offset + 4))
				return 0;
			if (off) {
				switch (m->in_op & FILE_OPS_MASK) {
				case FILE_OPAND:
					offset = (int32_t)((p->hl[3]<<24)|
							 (p->hl[2]<<16)|
							 (p->hl[1]<<8)|
							 (p->hl[0])) &
						 off;
					break;
				case FILE_OPOR:
					offset = (int32_t)((p->hl[3]<<24)|
							 (p->hl[2]<<16)|
							 (p->hl[1]<<8)|
							 (p->hl[0])) |
						 off;
					break;
				case FILE_OPXOR:
					offset = (int32_t)((p->hl[3]<<24)|
							 (p->hl[2]<<16)|
							 (p->hl[1]<<8)|
							 (p->hl[0])) ^
						 off;
					break;
				case FILE_OPADD:
					offset = (int32_t)((p->hl[3]<<24)|
							 (p->hl[2]<<16)|
							 (p->hl[1]<<8)|
							 (p->hl[0])) +
						 off;
					break;
				case FILE_OPMINUS:
					offset = (int32_t)((p->hl[3]<<24)|
							 (p->hl[2]<<16)|
							 (p->hl[1]<<8)|
							 (p->hl[0])) -
						 off;
					break;
				case FILE_OPMULTIPLY:
					offset = (int32_t)((p->hl[3]<<24)|
							 (p->hl[2]<<16)|
							 (p->hl[1]<<8)|
							 (p->hl[0])) *
						 off;
					break;
				case FILE_OPDIVIDE:
					offset = (int32_t)((p->hl[3]<<24)|
							 (p->hl[2]<<16)|
							 (p->hl[1]<<8)|
							 (p->hl[0])) /
						 off;
					break;
				case FILE_OPMODULO:
					offset = (int32_t)((p->hl[3]<<24)|
							 (p->hl[2]<<16)|
							 (p->hl[1]<<8)|
							 (p->hl[0])) %
						 off;
					break;
				}
			} else
				offset = (int32_t)((p->hl[3]<<24)|
						 (p->hl[2]<<16)|
						 (p->hl[1]<<8)|
						 (p->hl[0]));
			if (m->in_op & FILE_OPINVERSE)
				offset = ~offset;
			break;
		case FILE_MELONG:
			if (nbytes < (offset + 4))
				return 0;
			if (off) {
				switch (m->in_op & FILE_OPS_MASK) {
				case FILE_OPAND:
					offset = (int32_t)((p->hl[1]<<24)|
							 (p->hl[0]<<16)|
							 (p->hl[3]<<8)|
							 (p->hl[2])) &
						 off;
					break;
				case FILE_OPOR:
					offset = (int32_t)((p->hl[1]<<24)|
							 (p->hl[0]<<16)|
							 (p->hl[3]<<8)|
							 (p->hl[2])) |
						 off;
					break;
				case FILE_OPXOR:
					offset = (int32_t)((p->hl[1]<<24)|
							 (p->hl[0]<<16)|
							 (p->hl[3]<<8)|
							 (p->hl[2])) ^
						 off;
					break;
				case FILE_OPADD:
					offset = (int32_t)((p->hl[1]<<24)|
							 (p->hl[0]<<16)|
							 (p->hl[3]<<8)|
							 (p->hl[2])) +
						 off;
					break;
				case FILE_OPMINUS:
					offset = (int32_t)((p->hl[1]<<24)|
							 (p->hl[0]<<16)|
							 (p->hl[3]<<8)|
							 (p->hl[2])) -
						 off;
					break;
				case FILE_OPMULTIPLY:
					offset = (int32_t)((p->hl[1]<<24)|
							 (p->hl[0]<<16)|
							 (p->hl[3]<<8)|
							 (p->hl[2])) *
						 off;
					break;
				case FILE_OPDIVIDE:
					offset = (int32_t)((p->hl[1]<<24)|
							 (p->hl[0]<<16)|
							 (p->hl[3]<<8)|
							 (p->hl[2])) /
						 off;
					break;
				case FILE_OPMODULO:
					offset = (int32_t)((p->hl[1]<<24)|
							 (p->hl[0]<<16)|
							 (p->hl[3]<<8)|
							 (p->hl[2])) %
						 off;
					break;
				}
			} else
				offset = (int32_t)((p->hl[1]<<24)|
						 (p->hl[0]<<16)|
						 (p->hl[3]<<8)|
						 (p->hl[2]));
			if (m->in_op & FILE_OPINVERSE)
				offset = ~offset;
			break;
		case FILE_LONG:
			if (nbytes < (offset + 4))
				return 0;
			if (off) {
				switch (m->in_op & FILE_OPS_MASK) {
				case FILE_OPAND:
					offset = p->l & off;
					break;
				case FILE_OPOR:
					offset = p->l | off;
					break;
				case FILE_OPXOR:
					offset = p->l ^ off;
					break;
				case FILE_OPADD:
					offset = p->l + off;
					break;
				case FILE_OPMINUS:
					offset = p->l - off;
					break;
				case FILE_OPMULTIPLY:
					offset = p->l * off;
					break;
				case FILE_OPDIVIDE:
					offset = p->l / off;
					break;
				case FILE_OPMODULO:
					offset = p->l % off;
					break;
				}
			} else
				offset = p->l;
			if (m->in_op & FILE_OPINVERSE)
				offset = ~offset;
			break;
		}

		switch (cvt_flip(m->in_type, flip)) {
		case FILE_LEID3:
		case FILE_BEID3:
			offset = ((((offset >>  0) & 0x7f) <<  0) |
				 (((offset >>  8) & 0x7f) <<  7) |
				 (((offset >> 16) & 0x7f) << 14) |
				 (((offset >> 24) & 0x7f) << 21)) + 10;
			break;
		default:
			break;
		}

		if (m->flag & INDIROFFADD) {
			offset += ms->c.li[cont_level-1].off;
			if (offset == 0) {
				if ((ms->flags & MAGIC_DEBUG) != 0)
					fprintf(stderr,
					    "indirect *zero* offset\n");
				return 0;
			}
			if ((ms->flags & MAGIC_DEBUG) != 0)
				fprintf(stderr, "indirect +offs=%u\n", offset);
		}
		if (mcopy(ms, p, m->type, 0, s, offset, nbytes, count) == -1)
			return -1;
		ms->offset = offset;

		if ((ms->flags & MAGIC_DEBUG) != 0) {
			mdebug(offset, (char *)(void *)p,
			    sizeof(union VALUETYPE));
		}
	}

	/* Verify we have enough data to match magic type */
	switch (m->type) {
	case FILE_BYTE:
		if (nbytes < (offset + 1)) /* should alway be true */
			return 0;
		break;

	case FILE_SHORT:
	case FILE_BESHORT:
	case FILE_LESHORT:
		if (nbytes < (offset + 2))
			return 0;
		break;

	case FILE_LONG:
	case FILE_BELONG:
	case FILE_LELONG:
	case FILE_MELONG:
	case FILE_DATE:
	case FILE_BEDATE:
	case FILE_LEDATE:
	case FILE_MEDATE:
	case FILE_LDATE:
	case FILE_BELDATE:
	case FILE_LELDATE:
	case FILE_MELDATE:
	case FILE_FLOAT:
	case FILE_BEFLOAT:
	case FILE_LEFLOAT:
		if (nbytes < (offset + 4))
			return 0;
		break;

	case FILE_DOUBLE:
	case FILE_BEDOUBLE:
	case FILE_LEDOUBLE:
		if (nbytes < (offset + 8))
			return 0;
		break;

	case FILE_STRING:
	case FILE_PSTRING:
	case FILE_SEARCH:
		if (nbytes < (offset + m->vallen))
			return 0;
		break;

	case FILE_REGEX:
		if (nbytes < offset)
			return 0;
		break;

	case FILE_INDIRECT:
		if (nbytes < offset)
			return 0;
		sbuf = ms->o.buf;
		soffset = ms->offset;
		ms->o.buf = NULL;
		ms->offset = 0;
		rv = file_softmagic(ms, s + offset, nbytes - offset,
		    BINTEST, text);
		if ((ms->flags & MAGIC_DEBUG) != 0)
			fprintf(stderr, "indirect @offs=%u[%d]\n", offset, rv);
		rbuf = ms->o.buf;
		ms->o.buf = sbuf;
		ms->offset = soffset;
		if (rv == 1) {
	  	if ((ms->flags & (MAGIC_MIME|MAGIC_APPLE)) == 0 &&
			    file_printf(ms, m->desc, offset) == -1)
			return -1;
			if (file_printf(ms, "%s", rbuf) == -1)
				return -1;
			free(rbuf);
		}
		return rv;

	case FILE_USE:
		if (nbytes < offset)
			return 0;
		sbuf = m->value.s;
		if (*sbuf == '^') {
			sbuf++;
			flip = !flip;
		}
		if (file_magicfind(ms, sbuf, &ml) == -1) {
			file_error(ms, 0, "cannot find entry `%s'", sbuf);
			return -1;
		}

		oneed_separator = *need_separator;
		if (m->flag & NOSPACE)
			*need_separator = 0;
		rv = match(ms, ml.magic, ml.nmagic, s, nbytes, offset + o,
		    mode, text, flip, recursion_level, printed_something,
		    need_separator, returnval);
		if (rv != 1)
		    *need_separator = oneed_separator;
		return rv;

	case FILE_NAME:
		if (file_printf(ms, "%s", m->desc) == -1)
			return -1;
		return 1;
	case FILE_DEFAULT:	/* nothing to check */
	default:
		break;
	}
	if (!mconvert(ms, m, flip))
		return 0;

The mget function in libmagic/softmagic.c in the Fileinfo component in PHP 5.4.x before 5.4.16 allows remote attackers to cause a denial of service (invalid pointer dereference and application crash) via an MP3 file that triggers incorrect MIME type detection during access to an finfo object.


Fix FLI DOS -- CVE-2021-28676

* FliDecode did not properly check that the block advance was
  non-zero, potentally leading to an infinite loop on load.
* This dates to the PIL Fork
* Found with oss-fuzz

ImagingFliDecode(Imaging im, ImagingCodecState state, UINT8 *buf, Py_ssize_t bytes) {
    UINT8 *ptr;
    int framesize;
    int c, chunks, advance;
    int l, lines;
    int i, j, x = 0, y, ymax;

    /* If not even the chunk size is present, we'd better leave */

    if (bytes < 4) {
        return 0;
    }

    /* We don't decode anything unless we have a full chunk in the
       input buffer */

    ptr = buf;

    framesize = I32(ptr);
    if (framesize < I32(ptr)) {
        return 0;
    }

    /* Make sure this is a frame chunk.  The Python driver takes
       case of other chunk types. */

    if (bytes < 8) {
        state->errcode = IMAGING_CODEC_OVERRUN;
        return -1;
    }
    if (I16(ptr + 4) != 0xF1FA) {
        state->errcode = IMAGING_CODEC_UNKNOWN;
        return -1;
    }

    chunks = I16(ptr + 6);
    ptr += 16;
    bytes -= 16;

    /* Process subchunks */
    for (c = 0; c < chunks; c++) {
        UINT8 *data;
        if (bytes < 10) {
            state->errcode = IMAGING_CODEC_OVERRUN;
            return -1;
        }
        data = ptr + 6;
        switch (I16(ptr + 4)) {
            case 4:
            case 11:
                /* FLI COLOR chunk */
                break; /* ignored; handled by Python code */
            case 7:
                /* FLI SS2 chunk (word delta) */
                /* OOB ok, we've got 4 bytes min on entry */
                lines = I16(data);
                data += 2;
                for (l = y = 0; l < lines && y < state->ysize; l++, y++) {
                    UINT8 *local_buf = (UINT8 *)im->image[y];
                    int p, packets;
                    ERR_IF_DATA_OOB(2)
                    packets = I16(data);
                    data += 2;
                    while (packets & 0x8000) {
                        /* flag word */
                        if (packets & 0x4000) {
                            y += 65536 - packets; /* skip lines */
                            if (y >= state->ysize) {
                                state->errcode = IMAGING_CODEC_OVERRUN;
                                return -1;
                            }
                            local_buf = (UINT8 *)im->image[y];
                        } else {
                            /* store last byte (used if line width is odd) */
                            local_buf[state->xsize - 1] = (UINT8)packets;
                        }
                        ERR_IF_DATA_OOB(2)
                        packets = I16(data);
                        data += 2;
                    }
                    for (p = x = 0; p < packets; p++) {
                        ERR_IF_DATA_OOB(2)
                        x += data[0]; /* pixel skip */
                        if (data[1] >= 128) {
                            ERR_IF_DATA_OOB(4)
                            i = 256 - data[1]; /* run */
                            if (x + i + i > state->xsize) {
                                break;
                            }
                            for (j = 0; j < i; j++) {
                                local_buf[x++] = data[2];
                                local_buf[x++] = data[3];
                            }
                            data += 2 + 2;
                        } else {
                            i = 2 * (int)data[1]; /* chunk */
                            if (x + i > state->xsize) {
                                break;
                            }
                            ERR_IF_DATA_OOB(2 + i)
                            memcpy(local_buf + x, data + 2, i);
                            data += 2 + i;
                            x += i;
                        }
                    }
                    if (p < packets) {
                        break; /* didn't process all packets */
                    }
                }
                if (l < lines) {
                    /* didn't process all lines */
                    state->errcode = IMAGING_CODEC_OVERRUN;
                    return -1;
                }
                break;
            case 12:
                /* FLI LC chunk (byte delta) */
                /* OOB Check ok, we have 4 bytes min here */
                y = I16(data);
                ymax = y + I16(data + 2);
                data += 4;
                for (; y < ymax && y < state->ysize; y++) {
                    UINT8 *out = (UINT8 *)im->image[y];
                    ERR_IF_DATA_OOB(1)
                    int p, packets = *data++;
                    for (p = x = 0; p < packets; p++, x += i) {
                        ERR_IF_DATA_OOB(2)
                        x += data[0]; /* skip pixels */
                        if (data[1] & 0x80) {
                            i = 256 - data[1]; /* run */
                            if (x + i > state->xsize) {
                                break;
                            }
                            ERR_IF_DATA_OOB(3)
                            memset(out + x, data[2], i);
                            data += 3;
                        } else {
                            i = data[1]; /* chunk */
                            if (x + i > state->xsize) {
                                break;
                            }
                            ERR_IF_DATA_OOB(2 + i)
                            memcpy(out + x, data + 2, i);
                            data += i + 2;
                        }
                    }
                    if (p < packets) {
                        break; /* didn't process all packets */
                    }
                }
                if (y < ymax) {
                    /* didn't process all lines */
                    state->errcode = IMAGING_CODEC_OVERRUN;
                    return -1;
                }
                break;
            case 13:
                /* FLI BLACK chunk */
                for (y = 0; y < state->ysize; y++) {
                    memset(im->image[y], 0, state->xsize);
                }
                break;
            case 15:
                /* FLI BRUN chunk */
                /* OOB, ok, we've got 4 bytes min on entry */
                for (y = 0; y < state->ysize; y++) {
                    UINT8 *out = (UINT8 *)im->image[y];
                    data += 1; /* ignore packetcount byte */
                    for (x = 0; x < state->xsize; x += i) {
                        ERR_IF_DATA_OOB(2)
                        if (data[0] & 0x80) {
                            i = 256 - data[0];
                            if (x + i > state->xsize) {
                                break; /* safety first */
                            }
                            ERR_IF_DATA_OOB(i + 1)
                            memcpy(out + x, data + 1, i);
                            data += i + 1;
                        } else {
                            i = data[0];
                            if (x + i > state->xsize) {
                                break; /* safety first */
                            }
                            memset(out + x, data[1], i);
                            data += 2;
                        }
                    }
                    if (x != state->xsize) {
                        /* didn't unpack whole line */
                        state->errcode = IMAGING_CODEC_OVERRUN;
                        return -1;
                    }
                }
                break;
            case 16:
                /* COPY chunk */
                if (state->xsize > bytes / state->ysize) {
                    /* not enough data for frame */
                    return ptr - buf; /* bytes consumed */
                }
                for (y = 0; y < state->ysize; y++) {
                    UINT8 *local_buf = (UINT8 *)im->image[y];
                    memcpy(local_buf, data, state->xsize);
                    data += state->xsize;
                }
                break;
            case 18:
                /* PSTAMP chunk */
                break; /* ignored */
            default:
                /* unknown chunk */
                /* printf("unknown FLI/FLC chunk: %d\n", I16(ptr+4)); */
                state->errcode = IMAGING_CODEC_UNKNOWN;
                return -1;
        }
        advance = I32(ptr);
        if (advance < 0 || advance > bytes) {
            state->errcode = IMAGING_CODEC_OVERRUN;
            return -1;
        }
        ptr += advance;
        bytes -= advance;
    }

    return -1; /* end of frame */
}

An issue was discovered in Pillow before 8.2.0. For FLI data, FliDecode did not properly check that the block advance was non-zero, potentially leading to an infinite loop on load.


int vt_ioctl(struct tty_struct *tty,
	     unsigned int cmd, unsigned long arg)
{
	struct vc_data *vc = tty->driver_data;
	struct console_font_op op;	/* used in multiple places here */
	unsigned int console;
	unsigned char ucval;
	unsigned int uival;
	void __user *up = (void __user *)arg;
	int i, perm;
	int ret = 0;

	console = vc->vc_num;

	if (!vc_cons_allocated(console)) { 	/* impossible? */
		ret = -ENOIOCTLCMD;
		goto out;
	}

	/*
	 * To have permissions to do most of the vt ioctls, we either have
	 * to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
	 */
	perm = 0;
	if (current->signal->tty == tty || capable(CAP_SYS_TTY_CONFIG))
		perm = 1;

	switch (cmd) {
	case TIOCLINUX:
		ret = tioclinux(tty, arg);
		break;
	case KIOCSOUND:
		if (!perm)
			return -EPERM;
		/*
		 * The use of PIT_TICK_RATE is historic, it used to be
		 * the platform-dependent CLOCK_TICK_RATE between 2.6.12
		 * and 2.6.36, which was a minor but unfortunate ABI
		 * change. kd_mksound is locked by the input layer.
		 */
		if (arg)
			arg = PIT_TICK_RATE / arg;
		kd_mksound(arg, 0);
		break;

	case KDMKTONE:
		if (!perm)
			return -EPERM;
	{
		unsigned int ticks, count;

		/*
		 * Generate the tone for the appropriate number of ticks.
		 * If the time is zero, turn off sound ourselves.
		 */
		ticks = msecs_to_jiffies((arg >> 16) & 0xffff);
		count = ticks ? (arg & 0xffff) : 0;
		if (count)
			count = PIT_TICK_RATE / count;
		kd_mksound(count, ticks);
		break;
	}

	case KDGKBTYPE:
		/*
		 * this is naïve.
		 */
		ucval = KB_101;
		ret = put_user(ucval, (char __user *)arg);
		break;

		/*
		 * These cannot be implemented on any machine that implements
		 * ioperm() in user level (such as Alpha PCs) or not at all.
		 *
		 * XXX: you should never use these, just call ioperm directly..
		 */
#ifdef CONFIG_X86
	case KDADDIO:
	case KDDELIO:
		/*
		 * KDADDIO and KDDELIO may be able to add ports beyond what
		 * we reject here, but to be safe...
		 *
		 * These are locked internally via sys_ioperm
		 */
		if (arg < GPFIRST || arg > GPLAST) {
			ret = -EINVAL;
			break;
		}
		ret = ksys_ioperm(arg, 1, (cmd == KDADDIO)) ? -ENXIO : 0;
		break;

	case KDENABIO:
	case KDDISABIO:
		ret = ksys_ioperm(GPFIRST, GPNUM,
				  (cmd == KDENABIO)) ? -ENXIO : 0;
		break;
#endif

	/* Linux m68k/i386 interface for setting the keyboard delay/repeat rate */

	case KDKBDREP:
	{
		struct kbd_repeat kbrep;

		if (!capable(CAP_SYS_TTY_CONFIG))
			return -EPERM;

		if (copy_from_user(&kbrep, up, sizeof(struct kbd_repeat))) {
			ret =  -EFAULT;
			break;
		}
		ret = kbd_rate(&kbrep);
		if (ret)
			break;
		if (copy_to_user(up, &kbrep, sizeof(struct kbd_repeat)))
			ret = -EFAULT;
		break;
	}

	case KDSETMODE:
		/*
		 * currently, setting the mode from KD_TEXT to KD_GRAPHICS
		 * doesn't do a whole lot. i'm not sure if it should do any
		 * restoration of modes or what...
		 *
		 * XXX It should at least call into the driver, fbdev's definitely
		 * need to restore their engine state. --BenH
		 */
		if (!perm)
			return -EPERM;
		switch (arg) {
		case KD_GRAPHICS:
			break;
		case KD_TEXT0:
		case KD_TEXT1:
			arg = KD_TEXT;
		case KD_TEXT:
			break;
		default:
			ret = -EINVAL;
			goto out;
		}
		/* FIXME: this needs the console lock extending */
		if (vc->vc_mode == (unsigned char) arg)
			break;
		vc->vc_mode = (unsigned char) arg;
		if (console != fg_console)
			break;
		/*
		 * explicitly blank/unblank the screen if switching modes
		 */
		console_lock();
		if (arg == KD_TEXT)
			do_unblank_screen(1);
		else
			do_blank_screen(1);
		console_unlock();
		break;

	case KDGETMODE:
		uival = vc->vc_mode;
		goto setint;

	case KDMAPDISP:
	case KDUNMAPDISP:
		/*
		 * these work like a combination of mmap and KDENABIO.
		 * this could be easily finished.
		 */
		ret = -EINVAL;
		break;

	case KDSKBMODE:
		if (!perm)
			return -EPERM;
		ret = vt_do_kdskbmode(console, arg);
		if (ret == 0)
			tty_ldisc_flush(tty);
		break;

	case KDGKBMODE:
		uival = vt_do_kdgkbmode(console);
		ret = put_user(uival, (int __user *)arg);
		break;

	/* this could be folded into KDSKBMODE, but for compatibility
	   reasons it is not so easy to fold KDGKBMETA into KDGKBMODE */
	case KDSKBMETA:
		ret = vt_do_kdskbmeta(console, arg);
		break;

	case KDGKBMETA:
		/* FIXME: should review whether this is worth locking */
		uival = vt_do_kdgkbmeta(console);
	setint:
		ret = put_user(uival, (int __user *)arg);
		break;

	case KDGETKEYCODE:
	case KDSETKEYCODE:
		if(!capable(CAP_SYS_TTY_CONFIG))
			perm = 0;
		ret = vt_do_kbkeycode_ioctl(cmd, up, perm);
		break;

	case KDGKBENT:
	case KDSKBENT:
		ret = vt_do_kdsk_ioctl(cmd, up, perm, console);
		break;

	case KDGKBSENT:
	case KDSKBSENT:
		ret = vt_do_kdgkb_ioctl(cmd, up, perm);
		break;

	/* Diacritical processing. Handled in keyboard.c as it has
	   to operate on the keyboard locks and structures */
	case KDGKBDIACR:
	case KDGKBDIACRUC:
	case KDSKBDIACR:
	case KDSKBDIACRUC:
		ret = vt_do_diacrit(cmd, up, perm);
		break;

	/* the ioctls below read/set the flags usually shown in the leds */
	/* don't use them - they will go away without warning */
	case KDGKBLED:
	case KDSKBLED:
	case KDGETLED:
	case KDSETLED:
		ret = vt_do_kdskled(console, cmd, arg, perm);
		break;

	/*
	 * A process can indicate its willingness to accept signals
	 * generated by pressing an appropriate key combination.
	 * Thus, one can have a daemon that e.g. spawns a new console
	 * upon a keypress and then changes to it.
	 * See also the kbrequest field of inittab(5).
	 */
	case KDSIGACCEPT:
	{
		if (!perm || !capable(CAP_KILL))
			return -EPERM;
		if (!valid_signal(arg) || arg < 1 || arg == SIGKILL)
			ret = -EINVAL;
		else {
			spin_lock_irq(&vt_spawn_con.lock);
			put_pid(vt_spawn_con.pid);
			vt_spawn_con.pid = get_pid(task_pid(current));
			vt_spawn_con.sig = arg;
			spin_unlock_irq(&vt_spawn_con.lock);
		}
		break;
	}

	case VT_SETMODE:
	{
		struct vt_mode tmp;

		if (!perm)
			return -EPERM;
		if (copy_from_user(&tmp, up, sizeof(struct vt_mode))) {
			ret = -EFAULT;
			goto out;
		}
		if (tmp.mode != VT_AUTO && tmp.mode != VT_PROCESS) {
			ret = -EINVAL;
			goto out;
		}
		console_lock();
		vc->vt_mode = tmp;
		/* the frsig is ignored, so we set it to 0 */
		vc->vt_mode.frsig = 0;
		put_pid(vc->vt_pid);
		vc->vt_pid = get_pid(task_pid(current));
		/* no switch is required -- saw@shade.msu.ru */
		vc->vt_newvt = -1;
		console_unlock();
		break;
	}

	case VT_GETMODE:
	{
		struct vt_mode tmp;
		int rc;

		console_lock();
		memcpy(&tmp, &vc->vt_mode, sizeof(struct vt_mode));
		console_unlock();

		rc = copy_to_user(up, &tmp, sizeof(struct vt_mode));
		if (rc)
			ret = -EFAULT;
		break;
	}

	/*
	 * Returns global vt state. Note that VT 0 is always open, since
	 * it's an alias for the current VT, and people can't use it here.
	 * We cannot return state for more than 16 VTs, since v_state is short.
	 */
	case VT_GETSTATE:
	{
		struct vt_stat __user *vtstat = up;
		unsigned short state, mask;

		/* Review: FIXME: Console lock ? */
		if (put_user(fg_console + 1, &vtstat->v_active))
			ret = -EFAULT;
		else {
			state = 1;	/* /dev/tty0 is always open */
			for (i = 0, mask = 2; i < MAX_NR_CONSOLES && mask;
							++i, mask <<= 1)
				if (VT_IS_IN_USE(i))
					state |= mask;
			ret = put_user(state, &vtstat->v_state);
		}
		break;
	}

	/*
	 * Returns the first available (non-opened) console.
	 */
	case VT_OPENQRY:
		/* FIXME: locking ? - but then this is a stupid API */
		for (i = 0; i < MAX_NR_CONSOLES; ++i)
			if (! VT_IS_IN_USE(i))
				break;
		uival = i < MAX_NR_CONSOLES ? (i+1) : -1;
		goto setint;

	/*
	 * ioctl(fd, VT_ACTIVATE, num) will cause us to switch to vt # num,
	 * with num >= 1 (switches to vt 0, our console, are not allowed, just
	 * to preserve sanity).
	 */
	case VT_ACTIVATE:
		if (!perm)
			return -EPERM;
		if (arg == 0 || arg > MAX_NR_CONSOLES)
			ret =  -ENXIO;
		else {
			arg--;
			console_lock();
			ret = vc_allocate(arg);
			console_unlock();
			if (ret)
				break;
			set_console(arg);
		}
		break;

	case VT_SETACTIVATE:
	{
		struct vt_setactivate vsa;

		if (!perm)
			return -EPERM;

		if (copy_from_user(&vsa, (struct vt_setactivate __user *)arg,
					sizeof(struct vt_setactivate))) {
			ret = -EFAULT;
			goto out;
		}
		if (vsa.console == 0 || vsa.console > MAX_NR_CONSOLES)
			ret = -ENXIO;
		else {
			vsa.console = array_index_nospec(vsa.console,
							 MAX_NR_CONSOLES + 1);
			vsa.console--;
			console_lock();
			ret = vc_allocate(vsa.console);
			if (ret == 0) {
				struct vc_data *nvc;
				/* This is safe providing we don't drop the
				   console sem between vc_allocate and
				   finishing referencing nvc */
				nvc = vc_cons[vsa.console].d;
				nvc->vt_mode = vsa.mode;
				nvc->vt_mode.frsig = 0;
				put_pid(nvc->vt_pid);
				nvc->vt_pid = get_pid(task_pid(current));
			}
			console_unlock();
			if (ret)
				break;
			/* Commence switch and lock */
			/* Review set_console locks */
			set_console(vsa.console);
		}
		break;
	}

	/*
	 * wait until the specified VT has been activated
	 */
	case VT_WAITACTIVE:
		if (!perm)
			return -EPERM;
		if (arg == 0 || arg > MAX_NR_CONSOLES)
			ret = -ENXIO;
		else
			ret = vt_waitactive(arg);
		break;

	/*
	 * If a vt is under process control, the kernel will not switch to it
	 * immediately, but postpone the operation until the process calls this
	 * ioctl, allowing the switch to complete.
	 *
	 * According to the X sources this is the behavior:
	 *	0:	pending switch-from not OK
	 *	1:	pending switch-from OK
	 *	2:	completed switch-to OK
	 */
	case VT_RELDISP:
		if (!perm)
			return -EPERM;

		console_lock();
		if (vc->vt_mode.mode != VT_PROCESS) {
			console_unlock();
			ret = -EINVAL;
			break;
		}
		/*
		 * Switching-from response
		 */
		if (vc->vt_newvt >= 0) {
			if (arg == 0)
				/*
				 * Switch disallowed, so forget we were trying
				 * to do it.
				 */
				vc->vt_newvt = -1;

			else {
				/*
				 * The current vt has been released, so
				 * complete the switch.
				 */
				int newvt;
				newvt = vc->vt_newvt;
				vc->vt_newvt = -1;
				ret = vc_allocate(newvt);
				if (ret) {
					console_unlock();
					break;
				}
				/*
				 * When we actually do the console switch,
				 * make sure we are atomic with respect to
				 * other console switches..
				 */
				complete_change_console(vc_cons[newvt].d);
			}
		} else {
			/*
			 * Switched-to response
			 */
			/*
			 * If it's just an ACK, ignore it
			 */
			if (arg != VT_ACKACQ)
				ret = -EINVAL;
		}
		console_unlock();
		break;

	 /*
	  * Disallocate memory associated to VT (but leave VT1)
	  */
	 case VT_DISALLOCATE:
		if (arg > MAX_NR_CONSOLES) {
			ret = -ENXIO;
			break;
		}
		if (arg == 0)
			vt_disallocate_all();
		else
			ret = vt_disallocate(--arg);
		break;

	case VT_RESIZE:
	{
		struct vt_sizes __user *vtsizes = up;
		struct vc_data *vc;

		ushort ll,cc;
		if (!perm)
			return -EPERM;
		if (get_user(ll, &vtsizes->v_rows) ||
		    get_user(cc, &vtsizes->v_cols))
			ret = -EFAULT;
		else {
			console_lock();
			for (i = 0; i < MAX_NR_CONSOLES; i++) {
				vc = vc_cons[i].d;

				if (vc) {
					vc->vc_resize_user = 1;
					/* FIXME: review v tty lock */
					vc_resize(vc_cons[i].d, cc, ll);
				}
			}
			console_unlock();
		}
		break;
	}

	case VT_RESIZEX:
	{
		struct vt_consize v;
		if (!perm)
			return -EPERM;
		if (copy_from_user(&v, up, sizeof(struct vt_consize)))
			return -EFAULT;
		/* FIXME: Should check the copies properly */
		if (!v.v_vlin)
			v.v_vlin = vc->vc_scan_lines;
		if (v.v_clin) {
			int rows = v.v_vlin/v.v_clin;
			if (v.v_rows != rows) {
				if (v.v_rows) /* Parameters don't add up */
					return -EINVAL;
				v.v_rows = rows;
			}
		}
		if (v.v_vcol && v.v_ccol) {
			int cols = v.v_vcol/v.v_ccol;
			if (v.v_cols != cols) {
				if (v.v_cols)
					return -EINVAL;
				v.v_cols = cols;
			}
		}

		if (v.v_clin > 32)
			return -EINVAL;

		for (i = 0; i < MAX_NR_CONSOLES; i++) {
			if (!vc_cons[i].d)
				continue;
			console_lock();
			if (v.v_vlin)
				vc_cons[i].d->vc_scan_lines = v.v_vlin;
			if (v.v_clin)
				vc_cons[i].d->vc_font.height = v.v_clin;
			vc_cons[i].d->vc_resize_user = 1;
			vc_resize(vc_cons[i].d, v.v_cols, v.v_rows);
			console_unlock();
		}
		break;
	}

	case PIO_FONT: {
		if (!perm)
			return -EPERM;
		op.op = KD_FONT_OP_SET;
		op.flags = KD_FONT_FLAG_OLD | KD_FONT_FLAG_DONT_RECALC;	/* Compatibility */
		op.width = 8;
		op.height = 0;
		op.charcount = 256;
		op.data = up;
		ret = con_font_op(vc_cons[fg_console].d, &op);
		break;
	}

	case GIO_FONT: {
		op.op = KD_FONT_OP_GET;
		op.flags = KD_FONT_FLAG_OLD;
		op.width = 8;
		op.height = 32;
		op.charcount = 256;
		op.data = up;
		ret = con_font_op(vc_cons[fg_console].d, &op);
		break;
	}

	case PIO_CMAP:
                if (!perm)
			ret = -EPERM;
		else
	                ret = con_set_cmap(up);
		break;

	case GIO_CMAP:
                ret = con_get_cmap(up);
		break;

	case PIO_FONTX:
	case GIO_FONTX:
		ret = do_fontx_ioctl(cmd, up, perm, &op);
		break;

	case PIO_FONTRESET:
	{
		if (!perm)
			return -EPERM;

#ifdef BROKEN_GRAPHICS_PROGRAMS
		/* With BROKEN_GRAPHICS_PROGRAMS defined, the default
		   font is not saved. */
		ret = -ENOSYS;
		break;
#else
		{
		op.op = KD_FONT_OP_SET_DEFAULT;
		op.data = NULL;
		ret = con_font_op(vc_cons[fg_console].d, &op);
		if (ret)
			break;
		console_lock();
		con_set_default_unimap(vc_cons[fg_console].d);
		console_unlock();
		break;
		}
#endif
	}

	case KDFONTOP: {
		if (copy_from_user(&op, up, sizeof(op))) {
			ret = -EFAULT;
			break;
		}
		if (!perm && op.op != KD_FONT_OP_GET)
			return -EPERM;
		ret = con_font_op(vc, &op);
		if (ret)
			break;
		if (copy_to_user(up, &op, sizeof(op)))
			ret = -EFAULT;
		break;
	}

	case PIO_SCRNMAP:
		if (!perm)
			ret = -EPERM;
		else
			ret = con_set_trans_old(up);
		break;

	case GIO_SCRNMAP:
		ret = con_get_trans_old(up);
		break;

	case PIO_UNISCRNMAP:
		if (!perm)
			ret = -EPERM;
		else
			ret = con_set_trans_new(up);
		break;

	case GIO_UNISCRNMAP:
		ret = con_get_trans_new(up);
		break;

	case PIO_UNIMAPCLR:
		if (!perm)
			return -EPERM;
		con_clear_unimap(vc);
		break;

	case PIO_UNIMAP:
	case GIO_UNIMAP:
		ret = do_unimap_ioctl(cmd, up, perm, vc);
		break;

	case VT_LOCKSWITCH:
		if (!capable(CAP_SYS_TTY_CONFIG))
			return -EPERM;
		vt_dont_switch = 1;
		break;
	case VT_UNLOCKSWITCH:
		if (!capable(CAP_SYS_TTY_CONFIG))
			return -EPERM;
		vt_dont_switch = 0;
		break;
	case VT_GETHIFONTMASK:
		ret = put_user(vc->vc_hi_font_mask,
					(unsigned short __user *)arg);
		break;
	case VT_WAITEVENT:
		ret = vt_event_wait_ioctl((struct vt_event __user *)arg);
		break;
	default:
		ret = -ENOIOCTLCMD;
	}
out:
	return ret;
}

A race condition in the Linux kernel before 5.5.7 involving VT_RESIZEX could lead to a NULL pointer dereference and general protection fault.


Fix some pipelines to be safe if downstream write fails (fuzz issue 28262)

Pl_ASCIIHexDecoder::flush()
{
    if (this->pos == 0)
    {
	QTC::TC("libtests", "Pl_ASCIIHexDecoder no-op flush");
	return;
    }
    int b[2];
    for (int i = 0; i < 2; ++i)
    {
	if (this->inbuf[i] >= 'A')
	{
	    b[i] = this->inbuf[i] - 'A' + 10;
	}
	else
	{
	    b[i] = this->inbuf[i] - '0';
	}
    }
    unsigned char ch = static_cast<unsigned char>((b[0] << 4) + b[1]);

    QTC::TC("libtests", "Pl_ASCIIHexDecoder partial flush",
	    (this->pos == 2) ? 0 : 1);
    getNext()->write(&ch, 1);

    this->pos = 0;
    this->inbuf[0] = '0';
    this->inbuf[1] = '0';
    this->inbuf[2] = '\0';
}

QPDF 9.x through 9.1.1 and 10.x through 10.0.4 has a heap-based buffer overflow in Pl_ASCII85Decoder::write (called from Pl_AES_PDF::flush and Pl_AES_PDF::finish) when a certain downstream write fails.


Pl_AES_PDF::flush(bool strip_padding)
{
    assert(this->offset == this->buf_size);

    if (first)
    {
	first = false;
        bool return_after_init = false;
	if (this->cbc_mode)
	{
	    if (encrypt)
	    {
		// Set cbc_block to the initialization vector, and if
		// not zero, write it to the output stream.
		initializeVector();
                if (! (this->use_zero_iv || this->use_specified_iv))
                {
                    getNext()->write(this->cbc_block, this->buf_size);
                }
	    }
	    else if (this->use_zero_iv || this->use_specified_iv)
            {
                // Initialize vector with zeroes; zero vector was not
                // written to the beginning of the input file.
                initializeVector();
            }
            else
	    {
		// Take the first block of input as the initialization
		// vector.  There's nothing to write at this time.
		memcpy(this->cbc_block, this->inbuf, this->buf_size);
		this->offset = 0;
                return_after_init = true;
	    }
	}
        this->crypto->rijndael_init(
            encrypt, this->key.get(), key_bytes,
            this->cbc_mode, this->cbc_block);
        if (return_after_init)
        {
            return;
        }
    }

    if (this->encrypt)
    {
	this->crypto->rijndael_process(this->inbuf, this->outbuf);
    }
    else
    {
	this->crypto->rijndael_process(this->inbuf, this->outbuf);
    }
    unsigned int bytes = this->buf_size;
    if (strip_padding)
    {
	unsigned char last = this->outbuf[this->buf_size - 1];
	if (last <= this->buf_size)
	{
	    bool strip = true;
	    for (unsigned int i = 1; i <= last; ++i)
	    {
		if (this->outbuf[this->buf_size - i] != last)
		{
		    strip = false;
		    break;
		}
	    }
	    if (strip)
	    {
		bytes -= last;
	    }
	}
    }
    getNext()->write(this->outbuf, bytes);
    this->offset = 0;
}


Pl_ASCII85Decoder::flush()
{
    if (this->pos == 0)
    {
	QTC::TC("libtests", "Pl_ASCII85Decoder no-op flush");
	return;
    }
    unsigned long lval = 0;
    for (int i = 0; i < 5; ++i)
    {
	lval *= 85;
	lval += (this->inbuf[i] - 33U);
    }

    unsigned char outbuf[4];
    memset(outbuf, 0, 4);
    for (int i = 3; i >= 0; --i)
    {
	outbuf[i] = lval & 0xff;
	lval >>= 8;
    }

    QTC::TC("libtests", "Pl_ASCII85Decoder partial flush",
	    (this->pos == 5) ? 0 : 1);
    getNext()->write(outbuf, this->pos - 1);

    this->pos = 0;
    memset(this->inbuf, 117, 5);
}


Pl_Count::write(unsigned char* buf, size_t len)
{
    if (len)
    {
	this->m->count += QIntC::to_offset(len);
	getNext()->write(buf, len);
	this->m->last_char = buf[len - 1];
    }
}


HID: core: Sanitize event code and type when mapping input

When calling into hid_map_usage(), the passed event code is
blindly stored as is, even if it doesn't fit in the associated bitmap.

This event code can come from a variety of sources, including devices
masquerading as input devices, only a bit more "programmable".

Instead of taking the event code at face value, check that it actually
fits the corresponding bitmap, and if it doesn't:
- spit out a warning so that we know which device is acting up
- NULLify the bitmap pointer so that we catch unexpected uses

Code paths that can make use of untrusted inputs can now check
that the mapping was indeed correct and bail out if not.

Cc: stable@vger.kernel.org
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>

static int mt_touch_input_mapping(struct hid_device *hdev, struct hid_input *hi,
		struct hid_field *field, struct hid_usage *usage,
		unsigned long **bit, int *max, struct mt_application *app)
{
	struct mt_device *td = hid_get_drvdata(hdev);
	struct mt_class *cls = &td->mtclass;
	int code;
	struct hid_usage *prev_usage = NULL;

	/*
	 * Model touchscreens providing buttons as touchpads.
	 */
	if (field->application == HID_DG_TOUCHSCREEN &&
	    (usage->hid & HID_USAGE_PAGE) == HID_UP_BUTTON) {
		app->mt_flags |= INPUT_MT_POINTER;
		td->inputmode_value = MT_INPUTMODE_TOUCHPAD;
	}

	/* count the buttons on touchpads */
	if ((usage->hid & HID_USAGE_PAGE) == HID_UP_BUTTON)
		app->buttons_count++;

	if (usage->usage_index)
		prev_usage = &field->usage[usage->usage_index - 1];

	switch (usage->hid & HID_USAGE_PAGE) {

	case HID_UP_GENDESK:
		switch (usage->hid) {
		case HID_GD_X:
			if (prev_usage && (prev_usage->hid == usage->hid)) {
				code = ABS_MT_TOOL_X;
				MT_STORE_FIELD(cx);
			} else {
				code = ABS_MT_POSITION_X;
				MT_STORE_FIELD(x);
			}

			set_abs(hi->input, code, field, cls->sn_move);

			/*
			 * A system multi-axis that exports X and Y has a high
			 * chance of being used directly on a surface
			 */
			if (field->application == HID_GD_SYSTEM_MULTIAXIS) {
				__set_bit(INPUT_PROP_DIRECT,
					  hi->input->propbit);
				input_set_abs_params(hi->input,
						     ABS_MT_TOOL_TYPE,
						     MT_TOOL_DIAL,
						     MT_TOOL_DIAL, 0, 0);
			}

			return 1;
		case HID_GD_Y:
			if (prev_usage && (prev_usage->hid == usage->hid)) {
				code = ABS_MT_TOOL_Y;
				MT_STORE_FIELD(cy);
			} else {
				code = ABS_MT_POSITION_Y;
				MT_STORE_FIELD(y);
			}

			set_abs(hi->input, code, field, cls->sn_move);

			return 1;
		}
		return 0;

	case HID_UP_DIGITIZER:
		switch (usage->hid) {
		case HID_DG_INRANGE:
			if (app->quirks & MT_QUIRK_HOVERING) {
				input_set_abs_params(hi->input,
					ABS_MT_DISTANCE, 0, 1, 0, 0);
			}
			MT_STORE_FIELD(inrange_state);
			return 1;
		case HID_DG_CONFIDENCE:
			if (cls->name == MT_CLS_WIN_8 &&
				(field->application == HID_DG_TOUCHPAD ||
				 field->application == HID_DG_TOUCHSCREEN))
				app->quirks |= MT_QUIRK_CONFIDENCE;

			if (app->quirks & MT_QUIRK_CONFIDENCE)
				input_set_abs_params(hi->input,
						     ABS_MT_TOOL_TYPE,
						     MT_TOOL_FINGER,
						     MT_TOOL_PALM, 0, 0);

			MT_STORE_FIELD(confidence_state);
			return 1;
		case HID_DG_TIPSWITCH:
			if (field->application != HID_GD_SYSTEM_MULTIAXIS)
				input_set_capability(hi->input,
						     EV_KEY, BTN_TOUCH);
			MT_STORE_FIELD(tip_state);
			return 1;
		case HID_DG_CONTACTID:
			MT_STORE_FIELD(contactid);
			app->touches_by_report++;
			return 1;
		case HID_DG_WIDTH:
			if (!(app->quirks & MT_QUIRK_NO_AREA))
				set_abs(hi->input, ABS_MT_TOUCH_MAJOR, field,
					cls->sn_width);
			MT_STORE_FIELD(w);
			return 1;
		case HID_DG_HEIGHT:
			if (!(app->quirks & MT_QUIRK_NO_AREA)) {
				set_abs(hi->input, ABS_MT_TOUCH_MINOR, field,
					cls->sn_height);

				/*
				 * Only set ABS_MT_ORIENTATION if it is not
				 * already set by the HID_DG_AZIMUTH usage.
				 */
				if (!test_bit(ABS_MT_ORIENTATION,
						hi->input->absbit))
					input_set_abs_params(hi->input,
						ABS_MT_ORIENTATION, 0, 1, 0, 0);
			}
			MT_STORE_FIELD(h);
			return 1;
		case HID_DG_TIPPRESSURE:
			set_abs(hi->input, ABS_MT_PRESSURE, field,
				cls->sn_pressure);
			MT_STORE_FIELD(p);
			return 1;
		case HID_DG_SCANTIME:
			input_set_capability(hi->input, EV_MSC, MSC_TIMESTAMP);
			app->scantime = &field->value[usage->usage_index];
			app->scantime_logical_max = field->logical_maximum;
			return 1;
		case HID_DG_CONTACTCOUNT:
			app->have_contact_count = true;
			app->raw_cc = &field->value[usage->usage_index];
			return 1;
		case HID_DG_AZIMUTH:
			/*
			 * Azimuth has the range of [0, MAX) representing a full
			 * revolution. Set ABS_MT_ORIENTATION to a quarter of
			 * MAX according the definition of ABS_MT_ORIENTATION
			 */
			input_set_abs_params(hi->input, ABS_MT_ORIENTATION,
				-field->logical_maximum / 4,
				field->logical_maximum / 4,
				cls->sn_move ?
				field->logical_maximum / cls->sn_move : 0, 0);
			MT_STORE_FIELD(a);
			return 1;
		case HID_DG_CONTACTMAX:
			/* contact max are global to the report */
			return -1;
		case HID_DG_TOUCH:
			/* Legacy devices use TIPSWITCH and not TOUCH.
			 * Let's just ignore this field. */
			return -1;
		}
		/* let hid-input decide for the others */
		return 0;

	case HID_UP_BUTTON:
		code = BTN_MOUSE + ((usage->hid - 1) & HID_USAGE);
		/*
		 * MS PTP spec says that external buttons left and right have
		 * usages 2 and 3.
		 */
		if ((app->quirks & MT_QUIRK_WIN8_PTP_BUTTONS) &&
		    field->application == HID_DG_TOUCHPAD &&
		    (usage->hid & HID_USAGE) > 1)
			code--;

		if (field->application == HID_GD_SYSTEM_MULTIAXIS)
			code = BTN_0  + ((usage->hid - 1) & HID_USAGE);

		hid_map_usage(hi, usage, bit, max, EV_KEY, code);
		input_set_capability(hi->input, EV_KEY, code);
		return 1;

	case 0xff000000:
		/* we do not want to map these: no input-oriented meaning */
		return -1;
	}

	return 0;
}

In various methods of hid-multitouch.c, there is a possible out of bounds write due to a missing bounds check. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation.Product: AndroidVersions: Android kernelAndroid ID: A-162844689References: Upstream kernel


ecc: Add input validation for X25519.

* cipher/ecc.c (ecc_decrypt_raw): Add input validation.
* mpi/ec.c (ec_p_init): Use scratch buffer for bad points.
(_gcry_mpi_ec_bad_point): New.

--

Following is the paper describing the attack:

    May the Fourth Be With You: A Microarchitectural Side Channel Attack
    on Real-World Applications of Curve25519
    by Daniel Genkin, Luke Valenta, and Yuval Yarom

In the current implementation, we do output checking and it results an
error for those bad points.  However, when attacked, the computation
will done with leak of private key, even it will results errors.  To
mitigate leak, we added input validation.

Note that we only list bad points with MSB=0.  By X25519, MSB is
always cleared.

In future, we should implement constant-time field computation.  Then,
this input validation could be removed, if performance is important
and we are sure for no leak.

CVE-id: CVE-2017-0379
Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>

ec_p_init (mpi_ec_t ctx, enum gcry_mpi_ec_models model,
           enum ecc_dialects dialect,
           int flags,
           gcry_mpi_t p, gcry_mpi_t a, gcry_mpi_t b)
{
  int i;
  static int use_barrett;

  if (!use_barrett)
    {
      if (getenv ("GCRYPT_BARRETT"))
        use_barrett = 1;
      else
        use_barrett = -1;
    }

  /* Fixme: Do we want to check some constraints? e.g.  a < p  */

  ctx->model = model;
  ctx->dialect = dialect;
  ctx->flags = flags;
  if (dialect == ECC_DIALECT_ED25519)
    ctx->nbits = 256;
  else
    ctx->nbits = mpi_get_nbits (p);
  ctx->p = mpi_copy (p);
  ctx->a = mpi_copy (a);
  ctx->b = mpi_copy (b);

  ctx->t.p_barrett = use_barrett > 0? _gcry_mpi_barrett_init (ctx->p, 0):NULL;

  _gcry_mpi_ec_get_reset (ctx);

  /* Allocate scratch variables.  */
  for (i=0; i< DIM(ctx->t.scratch); i++)
    ctx->t.scratch[i] = mpi_alloc_like (ctx->p);

  /* Prepare for fast reduction.  */
  /* FIXME: need a test for NIST values.  However it does not gain us
     any real advantage, for 384 bits it is actually slower than using
     mpi_mulm.  */
/*   ctx->nist_nbits = mpi_get_nbits (ctx->p); */
/*   if (ctx->nist_nbits == 192) */
/*     { */
/*       for (i=0; i < 4; i++) */
/*         ctx->s[i] = mpi_new (192); */
/*       ctx->c    = mpi_new (192*2); */
/*     } */
/*   else if (ctx->nist_nbits == 384) */
/*     { */
/*       for (i=0; i < 10; i++) */
/*         ctx->s[i] = mpi_new (384); */
/*       ctx->c    = mpi_new (384*2); */
/*     } */
}

Libgcrypt before 1.8.1 does not properly consider Curve25519 side-channel attacks, which makes it easier for attackers to discover a secret key, related to cipher/ecc.c and mpi/ec.c.


ecc_decrypt_raw (gcry_sexp_t *r_plain, gcry_sexp_t s_data, gcry_sexp_t keyparms)
{
  unsigned int nbits;
  gpg_err_code_t rc;
  struct pk_encoding_ctx ctx;
  gcry_sexp_t l1 = NULL;
  gcry_mpi_t data_e = NULL;
  ECC_secret_key sk;
  gcry_mpi_t mpi_g = NULL;
  char *curvename = NULL;
  mpi_ec_t ec = NULL;
  mpi_point_struct kG;
  mpi_point_struct R;
  gcry_mpi_t r = NULL;
  int flags = 0;

  memset (&sk, 0, sizeof sk);
  point_init (&kG);
  point_init (&R);

  _gcry_pk_util_init_encoding_ctx (&ctx, PUBKEY_OP_DECRYPT,
                                   (nbits = ecc_get_nbits (keyparms)));

  /* Look for flags. */
  l1 = sexp_find_token (keyparms, "flags", 0);
  if (l1)
    {
      rc = _gcry_pk_util_parse_flaglist (l1, &flags, NULL);
      if (rc)
        goto leave;
    }
  sexp_release (l1);
  l1 = NULL;

  /*
   * Extract the data.
   */
  rc = _gcry_pk_util_preparse_encval (s_data, ecc_names, &l1, &ctx);
  if (rc)
    goto leave;
  rc = sexp_extract_param (l1, NULL, "e", &data_e, NULL);
  if (rc)
    goto leave;
  if (DBG_CIPHER)
    log_printmpi ("ecc_decrypt  d_e", data_e);
  if (mpi_is_opaque (data_e))
    {
      rc = GPG_ERR_INV_DATA;
      goto leave;
    }

  /*
   * Extract the key.
   */
  rc = sexp_extract_param (keyparms, NULL, "-p?a?b?g?n?h?+d",
                           &sk.E.p, &sk.E.a, &sk.E.b, &mpi_g, &sk.E.n,
                           &sk.E.h, &sk.d, NULL);
  if (rc)
    goto leave;
  if (mpi_g)
    {
      point_init (&sk.E.G);
      rc = _gcry_ecc_os2ec (&sk.E.G, mpi_g);
      if (rc)
        goto leave;
    }
  /* Add missing parameters using the optional curve parameter.  */
  sexp_release (l1);
  l1 = sexp_find_token (keyparms, "curve", 5);
  if (l1)
    {
      curvename = sexp_nth_string (l1, 1);
      if (curvename)
        {
          rc = _gcry_ecc_fill_in_curve (0, curvename, &sk.E, NULL);
          if (rc)
            goto leave;
        }
    }
  /* Guess required fields if a curve parameter has not been given.  */
  if (!curvename)
    {
      sk.E.model = MPI_EC_WEIERSTRASS;
      sk.E.dialect = ECC_DIALECT_STANDARD;
      if (!sk.E.h)
	sk.E.h = mpi_const (MPI_C_ONE);
    }
  if (DBG_CIPHER)
    {
      log_debug ("ecc_decrypt info: %s/%s\n",
                 _gcry_ecc_model2str (sk.E.model),
                 _gcry_ecc_dialect2str (sk.E.dialect));
      if (sk.E.name)
        log_debug  ("ecc_decrypt name: %s\n", sk.E.name);
      log_printmpi ("ecc_decrypt    p", sk.E.p);
      log_printmpi ("ecc_decrypt    a", sk.E.a);
      log_printmpi ("ecc_decrypt    b", sk.E.b);
      log_printpnt ("ecc_decrypt  g",   &sk.E.G, NULL);
      log_printmpi ("ecc_decrypt    n", sk.E.n);
      log_printmpi ("ecc_decrypt    h", sk.E.h);
      if (!fips_mode ())
        log_printmpi ("ecc_decrypt    d", sk.d);
    }
  if (!sk.E.p || !sk.E.a || !sk.E.b || !sk.E.G.x || !sk.E.n || !sk.E.h || !sk.d)
    {
      rc = GPG_ERR_NO_OBJ;
      goto leave;
    }

  ec = _gcry_mpi_ec_p_internal_new (sk.E.model, sk.E.dialect, flags,
                                    sk.E.p, sk.E.a, sk.E.b);

  /*
   * Compute the plaintext.
   */
  if (ec->model == MPI_EC_MONTGOMERY)
    rc = _gcry_ecc_mont_decodepoint (data_e, ec, &kG);
  else
    rc = _gcry_ecc_os2ec (&kG, data_e);
  if (rc)
    goto leave;

  if (DBG_CIPHER)
    log_printpnt ("ecc_decrypt    kG", &kG, NULL);

  if (!(flags & PUBKEY_FLAG_DJB_TWEAK)
      /* For X25519, by its definition, validation should not be done.  */
      && !_gcry_mpi_ec_curve_point (&kG, ec))
    {
      rc = GPG_ERR_INV_DATA;
      goto leave;
    }

  /* R = dkG */
  _gcry_mpi_ec_mul_point (&R, sk.d, &kG, ec);

  /* The following is false: assert( mpi_cmp_ui( R.x, 1 )==0 );, so:  */
  {
    gcry_mpi_t x, y;

    x = mpi_new (0);
    if (ec->model == MPI_EC_MONTGOMERY)
      y = NULL;
    else
      y = mpi_new (0);

    if (_gcry_mpi_ec_get_affine (x, y, &R, ec))
      {
        rc = GPG_ERR_INV_DATA;
        goto leave;
        /*
         * Note for X25519.
         *
         * By the definition of X25519, this is the case where X25519
         * returns 0, mapping infinity to zero.  However, we
         * deliberately let it return an error.
         *
         * For X25519 ECDH, comming here means that it might be
         * decrypted by anyone with the shared secret of 0 (the result
         * of this function could be always 0 by other scalar values,
         * other than the private key of SK.D).
         *
         * So, it looks like an encrypted message but it can be
         * decrypted by anyone, or at least something wrong
         * happens.  Recipient should not proceed as if it were
         * properly encrypted message.
         *
         * This handling is needed for our major usage of GnuPG,
         * where it does the One-Pass Diffie-Hellman method,
         * C(1, 1, ECC CDH), with an ephemeral key.
         */
      }

    if (y)
      r = _gcry_ecc_ec2os (x, y, sk.E.p);
    else
      {
        unsigned char *rawmpi;
        unsigned int rawmpilen;

        rawmpi = _gcry_mpi_get_buffer_extra (x, nbits/8, -1,
                                             &rawmpilen, NULL);
        if (!rawmpi)
          {
            rc = gpg_err_code_from_syserror ();
            goto leave;
          }
        else
          {
            rawmpi[0] = 0x40;
            rawmpilen++;
            r = mpi_new (0);
            mpi_set_opaque (r, rawmpi, rawmpilen*8);
          }
      }
    if (!r)
      rc = gpg_err_code_from_syserror ();
    else
      rc = 0;
    mpi_free (x);
    mpi_free (y);
  }
  if (DBG_CIPHER)
    log_printmpi ("ecc_decrypt  res", r);

  if (!rc)
    rc = sexp_build (r_plain, NULL, "(value %m)", r);

 leave:
  point_free (&R);
  point_free (&kG);
  _gcry_mpi_release (r);
  _gcry_mpi_release (sk.E.p);
  _gcry_mpi_release (sk.E.a);
  _gcry_mpi_release (sk.E.b);
  _gcry_mpi_release (mpi_g);
  point_free (&sk.E.G);
  _gcry_mpi_release (sk.E.n);
  _gcry_mpi_release (sk.E.h);
  _gcry_mpi_release (sk.d);
  _gcry_mpi_release (data_e);
  xfree (curvename);
  sexp_release (l1);
  _gcry_mpi_ec_free (ec);
  _gcry_pk_util_free_encoding_ctx (&ctx);
  if (DBG_CIPHER)
    log_debug ("ecc_decrypt    => %s\n", gpg_strerror (rc));
  return rc;
}


libvncclient/rfbproto: limit max textchat size

Addresses GitHub Security Lab (GHSL) Vulnerability Report
`GHSL-2020-063`.

Re #275

HandleRFBServerMessage(rfbClient* client)
{
  rfbServerToClientMsg msg;

  if (client->serverPort==-1)
    client->vncRec->readTimestamp = TRUE;
  if (!ReadFromRFBServer(client, (char *)&msg, 1))
    return FALSE;

  switch (msg.type) {

  case rfbSetColourMapEntries:
  {
    /* TODO:
    int i;
    uint16_t rgb[3];
    XColor xc;

    if (!ReadFromRFBServer(client, ((char *)&msg) + 1,
			   sz_rfbSetColourMapEntriesMsg - 1))
      return FALSE;

    msg.scme.firstColour = rfbClientSwap16IfLE(msg.scme.firstColour);
    msg.scme.nColours = rfbClientSwap16IfLE(msg.scme.nColours);

    for (i = 0; i < msg.scme.nColours; i++) {
      if (!ReadFromRFBServer(client, (char *)rgb, 6))
	return FALSE;
      xc.pixel = msg.scme.firstColour + i;
      xc.red = rfbClientSwap16IfLE(rgb[0]);
      xc.green = rfbClientSwap16IfLE(rgb[1]);
      xc.blue = rfbClientSwap16IfLE(rgb[2]);
      xc.flags = DoRed|DoGreen|DoBlue;
      XStoreColor(dpy, cmap, &xc);
    }
    */

    break;
  }

  case rfbFramebufferUpdate:
  {
    rfbFramebufferUpdateRectHeader rect;
    int linesToRead;
    int bytesPerLine;
    int i;

    if (!ReadFromRFBServer(client, ((char *)&msg.fu) + 1,
			   sz_rfbFramebufferUpdateMsg - 1))
      return FALSE;

    msg.fu.nRects = rfbClientSwap16IfLE(msg.fu.nRects);

    for (i = 0; i < msg.fu.nRects; i++) {
      if (!ReadFromRFBServer(client, (char *)&rect, sz_rfbFramebufferUpdateRectHeader))
	return FALSE;

      rect.encoding = rfbClientSwap32IfLE(rect.encoding);
      if (rect.encoding == rfbEncodingLastRect)
	break;

      rect.r.x = rfbClientSwap16IfLE(rect.r.x);
      rect.r.y = rfbClientSwap16IfLE(rect.r.y);
      rect.r.w = rfbClientSwap16IfLE(rect.r.w);
      rect.r.h = rfbClientSwap16IfLE(rect.r.h);

      if (rect.encoding == rfbEncodingXCursor ||
	  rect.encoding == rfbEncodingRichCursor) {

	if (!HandleCursorShape(client,
			       rect.r.x, rect.r.y, rect.r.w, rect.r.h,
			       rect.encoding)) {
	  return FALSE;
	}
	continue;
      }

      if (rect.encoding == rfbEncodingPointerPos) {
	if (!client->HandleCursorPos(client,rect.r.x, rect.r.y)) {
	  return FALSE;
	}
	continue;
      }

      if (rect.encoding == rfbEncodingKeyboardLedState) {
          /* OK! We have received a keyboard state message!!! */
          client->KeyboardLedStateEnabled = 1;
          if (client->HandleKeyboardLedState!=NULL)
              client->HandleKeyboardLedState(client, rect.r.x, 0);
          /* stash it for the future */
          client->CurrentKeyboardLedState = rect.r.x;
          continue;
      }

      if (rect.encoding == rfbEncodingNewFBSize) {
	client->width = rect.r.w;
	client->height = rect.r.h;
	client->updateRect.x = client->updateRect.y = 0;
	client->updateRect.w = client->width;
	client->updateRect.h = client->height;
	if (!client->MallocFrameBuffer(client))
	  return FALSE;
	SendFramebufferUpdateRequest(client, 0, 0, rect.r.w, rect.r.h, FALSE);
	rfbClientLog("Got new framebuffer size: %dx%d\n", rect.r.w, rect.r.h);
	continue;
      }

      /* rect.r.w=byte count */
      if (rect.encoding == rfbEncodingSupportedMessages) {
          int loop;
          if (!ReadFromRFBServer(client, (char *)&client->supportedMessages, sz_rfbSupportedMessages))
              return FALSE;

          /* msgs is two sets of bit flags of supported messages client2server[] and server2client[] */
          /* currently ignored by this library */

          rfbClientLog("client2server supported messages (bit flags)\n");
          for (loop=0;loop<32;loop+=8)
            rfbClientLog("%02X: %04x %04x %04x %04x - %04x %04x %04x %04x\n", loop,
                client->supportedMessages.client2server[loop],   client->supportedMessages.client2server[loop+1],
                client->supportedMessages.client2server[loop+2], client->supportedMessages.client2server[loop+3],
                client->supportedMessages.client2server[loop+4], client->supportedMessages.client2server[loop+5],
                client->supportedMessages.client2server[loop+6], client->supportedMessages.client2server[loop+7]);

          rfbClientLog("server2client supported messages (bit flags)\n");
          for (loop=0;loop<32;loop+=8)
            rfbClientLog("%02X: %04x %04x %04x %04x - %04x %04x %04x %04x\n", loop,
                client->supportedMessages.server2client[loop],   client->supportedMessages.server2client[loop+1],
                client->supportedMessages.server2client[loop+2], client->supportedMessages.server2client[loop+3],
                client->supportedMessages.server2client[loop+4], client->supportedMessages.server2client[loop+5],
                client->supportedMessages.server2client[loop+6], client->supportedMessages.server2client[loop+7]);
          continue;
      }

      /* rect.r.w=byte count, rect.r.h=# of encodings */
      if (rect.encoding == rfbEncodingSupportedEncodings) {
          char *buffer;
          buffer = malloc(rect.r.w);
          if (!ReadFromRFBServer(client, buffer, rect.r.w))
          {
              free(buffer);
              return FALSE;
          }

          /* buffer now contains rect.r.h # of uint32_t encodings that the server supports */
          /* currently ignored by this library */
          free(buffer);
          continue;
      }

      /* rect.r.w=byte count */
      if (rect.encoding == rfbEncodingServerIdentity) {
          char *buffer;
          buffer = malloc(rect.r.w+1);
          if (!ReadFromRFBServer(client, buffer, rect.r.w))
          {
              free(buffer);
              return FALSE;
          }
          buffer[rect.r.w]=0; /* null terminate, just in case */
          rfbClientLog("Connected to Server \"%s\"\n", buffer);
          free(buffer);
          continue;
      }

      /* rfbEncodingUltraZip is a collection of subrects.   x = # of subrects, and h is always 0 */
      if (rect.encoding != rfbEncodingUltraZip)
      {
        if ((rect.r.x + rect.r.w > client->width) ||
	    (rect.r.y + rect.r.h > client->height))
	    {
	      rfbClientLog("Rect too large: %dx%d at (%d, %d)\n",
	  	  rect.r.w, rect.r.h, rect.r.x, rect.r.y);
	      return FALSE;
            }

        /* UltraVNC with scaling, will send rectangles with a zero W or H
         *
        if ((rect.encoding != rfbEncodingTight) &&
            (rect.r.h * rect.r.w == 0))
        {
	  rfbClientLog("Zero size rect - ignoring (encoding=%d (0x%08x) %dx, %dy, %dw, %dh)\n", rect.encoding, rect.encoding, rect.r.x, rect.r.y, rect.r.w, rect.r.h);
	  continue;
        }
        */

        /* If RichCursor encoding is used, we should prevent collisions
	   between framebuffer updates and cursor drawing operations. */
        client->SoftCursorLockArea(client, rect.r.x, rect.r.y, rect.r.w, rect.r.h);
      }

      switch (rect.encoding) {

      case rfbEncodingRaw: {
	int y=rect.r.y, h=rect.r.h;

	bytesPerLine = rect.r.w * client->format.bitsPerPixel / 8;
	/* RealVNC 4.x-5.x on OSX can induce bytesPerLine==0,
	   usually during GPU accel. */
	/* Regardless of cause, do not divide by zero. */
	linesToRead = bytesPerLine ? (RFB_BUFFER_SIZE / bytesPerLine) : 0;

	while (linesToRead && h > 0) {
	  if (linesToRead > h)
	    linesToRead = h;

	  if (!ReadFromRFBServer(client, client->buffer,bytesPerLine * linesToRead))
	    return FALSE;

	  client->GotBitmap(client, (uint8_t *)client->buffer,
			   rect.r.x, y, rect.r.w,linesToRead);

	  h -= linesToRead;
	  y += linesToRead;

	}
	break;
      }

      case rfbEncodingCopyRect:
      {
	rfbCopyRect cr;

	if (!ReadFromRFBServer(client, (char *)&cr, sz_rfbCopyRect))
	  return FALSE;

	cr.srcX = rfbClientSwap16IfLE(cr.srcX);
	cr.srcY = rfbClientSwap16IfLE(cr.srcY);

	/* If RichCursor encoding is used, we should extend our
	   "cursor lock area" (previously set to destination
	   rectangle) to the source rectangle as well. */
	client->SoftCursorLockArea(client,
				   cr.srcX, cr.srcY, rect.r.w, rect.r.h);

        client->GotCopyRect(client, cr.srcX, cr.srcY, rect.r.w, rect.r.h,
                            rect.r.x, rect.r.y);

	break;
      }

      case rfbEncodingRRE:
      {
	switch (client->format.bitsPerPixel) {
	case 8:
	  if (!HandleRRE8(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
	    return FALSE;
	  break;
	case 16:
	  if (!HandleRRE16(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
	    return FALSE;
	  break;
	case 32:
	  if (!HandleRRE32(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
	    return FALSE;
	  break;
	}
	break;
      }

      case rfbEncodingCoRRE:
      {
	switch (client->format.bitsPerPixel) {
	case 8:
	  if (!HandleCoRRE8(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
	    return FALSE;
	  break;
	case 16:
	  if (!HandleCoRRE16(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
	    return FALSE;
	  break;
	case 32:
	  if (!HandleCoRRE32(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
	    return FALSE;
	  break;
	}
	break;
      }

      case rfbEncodingHextile:
      {
	switch (client->format.bitsPerPixel) {
	case 8:
	  if (!HandleHextile8(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
	    return FALSE;
	  break;
	case 16:
	  if (!HandleHextile16(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
	    return FALSE;
	  break;
	case 32:
	  if (!HandleHextile32(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
	    return FALSE;
	  break;
	}
	break;
      }

      case rfbEncodingUltra:
      {
        switch (client->format.bitsPerPixel) {
        case 8:
          if (!HandleUltra8(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
            return FALSE;
          break;
        case 16:
          if (!HandleUltra16(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
            return FALSE;
          break;
        case 32:
          if (!HandleUltra32(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
            return FALSE;
          break;
        }
        break;
      }
      case rfbEncodingUltraZip:
      {
        switch (client->format.bitsPerPixel) {
        case 8:
          if (!HandleUltraZip8(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
            return FALSE;
          break;
        case 16:
          if (!HandleUltraZip16(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
            return FALSE;
          break;
        case 32:
          if (!HandleUltraZip32(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
            return FALSE;
          break;
        }
        break;
      }

      case rfbEncodingTRLE:
	  {
        switch (client->format.bitsPerPixel) {
        case 8:
          if (!HandleTRLE8(client, rect.r.x, rect.r.y, rect.r.w, rect.r.h))
            return FALSE;
          break;
        case 16:
          if (client->si.format.greenMax > 0x1F) {
            if (!HandleTRLE16(client, rect.r.x, rect.r.y, rect.r.w, rect.r.h))
              return FALSE;
          } else {
            if (!HandleTRLE15(client, rect.r.x, rect.r.y, rect.r.w, rect.r.h))
              return FALSE;
          }
          break;
        case 32: {
          uint32_t maxColor =
              (client->format.redMax << client->format.redShift) |
              (client->format.greenMax << client->format.greenShift) |
              (client->format.blueMax << client->format.blueShift);
          if ((client->format.bigEndian && (maxColor & 0xff) == 0) ||
              (!client->format.bigEndian && (maxColor & 0xff000000) == 0)) {
            if (!HandleTRLE24(client, rect.r.x, rect.r.y, rect.r.w, rect.r.h))
              return FALSE;
          } else if (!client->format.bigEndian && (maxColor & 0xff) == 0) {
            if (!HandleTRLE24Up(client, rect.r.x, rect.r.y, rect.r.w, rect.r.h))
              return FALSE;
          } else if (client->format.bigEndian && (maxColor & 0xff000000) == 0) {
            if (!HandleTRLE24Down(client, rect.r.x, rect.r.y, rect.r.w,
                                  rect.r.h))
              return FALSE;
          } else if (!HandleTRLE32(client, rect.r.x, rect.r.y, rect.r.w,
                                   rect.r.h))
            return FALSE;
          break;
        }
        }
        break;
      }

#ifdef LIBVNCSERVER_HAVE_LIBZ
      case rfbEncodingZlib:
      {
	switch (client->format.bitsPerPixel) {
	case 8:
	  if (!HandleZlib8(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
	    return FALSE;
	  break;
	case 16:
	  if (!HandleZlib16(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
	    return FALSE;
	  break;
	case 32:
	  if (!HandleZlib32(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
	    return FALSE;
	  break;
	}
	break;
     }

#ifdef LIBVNCSERVER_HAVE_LIBJPEG
      case rfbEncodingTight:
      {
	switch (client->format.bitsPerPixel) {
	case 8:
	  if (!HandleTight8(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
	    return FALSE;
	  break;
	case 16:
	  if (!HandleTight16(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
	    return FALSE;
	  break;
	case 32:
	  if (!HandleTight32(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
	    return FALSE;
	  break;
	}
	break;
      }
#endif
      case rfbEncodingZRLE:
	/* Fail safe for ZYWRLE unsupport VNC server. */
	client->appData.qualityLevel = 9;
	/* fall through */
      case rfbEncodingZYWRLE:
      {
	switch (client->format.bitsPerPixel) {
	case 8:
	  if (!HandleZRLE8(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
	    return FALSE;
	  break;
	case 16:
	  if (client->si.format.greenMax > 0x1F) {
	    if (!HandleZRLE16(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
	      return FALSE;
	  } else {
	    if (!HandleZRLE15(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
	      return FALSE;
	  }
	  break;
	case 32:
	{
	  uint32_t maxColor=(client->format.redMax<<client->format.redShift)|
		(client->format.greenMax<<client->format.greenShift)|
		(client->format.blueMax<<client->format.blueShift);
	  if ((client->format.bigEndian && (maxColor&0xff)==0) ||
	      (!client->format.bigEndian && (maxColor&0xff000000)==0)) {
	    if (!HandleZRLE24(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
	      return FALSE;
	  } else if (!client->format.bigEndian && (maxColor&0xff)==0) {
	    if (!HandleZRLE24Up(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
	      return FALSE;
	  } else if (client->format.bigEndian && (maxColor&0xff000000)==0) {
	    if (!HandleZRLE24Down(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
	      return FALSE;
	  } else if (!HandleZRLE32(client, rect.r.x,rect.r.y,rect.r.w,rect.r.h))
	    return FALSE;
	  break;
	}
	}
	break;
     }

#endif

      default:
	 {
	   rfbBool handled = FALSE;
	   rfbClientProtocolExtension* e;

	   for(e = rfbClientExtensions; !handled && e; e = e->next)
	     if(e->handleEncoding && e->handleEncoding(client, &rect))
	       handled = TRUE;

	   if(!handled) {
	     rfbClientLog("Unknown rect encoding %d\n",
		 (int)rect.encoding);
	     return FALSE;
	   }
	 }
      }

      /* Now we may discard "soft cursor locks". */
      client->SoftCursorUnlockScreen(client);

      client->GotFrameBufferUpdate(client, rect.r.x, rect.r.y, rect.r.w, rect.r.h);
    }

    if (!SendIncrementalFramebufferUpdateRequest(client))
      return FALSE;

    if (client->FinishedFrameBufferUpdate)
      client->FinishedFrameBufferUpdate(client);

    break;
  }

  case rfbBell:
  {
    client->Bell(client);

    break;
  }

  case rfbServerCutText:
  {
    char *buffer;

    if (!ReadFromRFBServer(client, ((char *)&msg) + 1,
			   sz_rfbServerCutTextMsg - 1))
      return FALSE;

    msg.sct.length = rfbClientSwap32IfLE(msg.sct.length);

    if (msg.sct.length > 1<<20) {
	    rfbClientErr("Ignoring too big cut text length sent by server: %u B > 1 MB\n", (unsigned int)msg.sct.length);
	    return FALSE;
    }

    buffer = malloc(msg.sct.length+1);

    if (!ReadFromRFBServer(client, buffer, msg.sct.length)) {
      free(buffer);
      return FALSE;
    }

    buffer[msg.sct.length] = 0;

    if (client->GotXCutText)
      client->GotXCutText(client, buffer, msg.sct.length);

    free(buffer);

    break;
  }

  case rfbTextChat:
  {
      char *buffer=NULL;
      if (!ReadFromRFBServer(client, ((char *)&msg) + 1,
                             sz_rfbTextChatMsg- 1))
        return FALSE;
      msg.tc.length = rfbClientSwap32IfLE(msg.sct.length);
      switch(msg.tc.length) {
      case rfbTextChatOpen:
          rfbClientLog("Received TextChat Open\n");
          if (client->HandleTextChat!=NULL)
              client->HandleTextChat(client, (int)rfbTextChatOpen, NULL);
          break;
      case rfbTextChatClose:
          rfbClientLog("Received TextChat Close\n");
         if (client->HandleTextChat!=NULL)
              client->HandleTextChat(client, (int)rfbTextChatClose, NULL);
          break;
      case rfbTextChatFinished:
          rfbClientLog("Received TextChat Finished\n");
         if (client->HandleTextChat!=NULL)
              client->HandleTextChat(client, (int)rfbTextChatFinished, NULL);
          break;
      default:
          buffer=malloc(msg.tc.length+1);
          if (!ReadFromRFBServer(client, buffer, msg.tc.length))
          {
              free(buffer);
              return FALSE;
          }
          /* Null Terminate <just in case> */
          buffer[msg.tc.length]=0;
          rfbClientLog("Received TextChat \"%s\"\n", buffer);
          if (client->HandleTextChat!=NULL)
              client->HandleTextChat(client, (int)msg.tc.length, buffer);
          free(buffer);
          break;
      }
      break;
  }

  case rfbXvp:
  {
    if (!ReadFromRFBServer(client, ((char *)&msg) + 1,
                           sz_rfbXvpMsg -1))
      return FALSE;

    SetClient2Server(client, rfbXvp);
    /* technically, we only care what we can *send* to the server
     * but, we set Server2Client Just in case it ever becomes useful
     */
    SetServer2Client(client, rfbXvp);

    if(client->HandleXvpMsg)
      client->HandleXvpMsg(client, msg.xvp.version, msg.xvp.code);

    break;
  }

  case rfbResizeFrameBuffer:
  {
    if (!ReadFromRFBServer(client, ((char *)&msg) + 1,
                           sz_rfbResizeFrameBufferMsg -1))
      return FALSE;
    client->width = rfbClientSwap16IfLE(msg.rsfb.framebufferWidth);
    client->height = rfbClientSwap16IfLE(msg.rsfb.framebufferHeigth);
    client->updateRect.x = client->updateRect.y = 0;
    client->updateRect.w = client->width;
    client->updateRect.h = client->height;
    if (!client->MallocFrameBuffer(client))
      return FALSE;

    SendFramebufferUpdateRequest(client, 0, 0, client->width, client->height, FALSE);
    rfbClientLog("Got new framebuffer size: %dx%d\n", client->width, client->height);
    break;
  }

  case rfbPalmVNCReSizeFrameBuffer:
  {
    if (!ReadFromRFBServer(client, ((char *)&msg) + 1,
                           sz_rfbPalmVNCReSizeFrameBufferMsg -1))
      return FALSE;
    client->width = rfbClientSwap16IfLE(msg.prsfb.buffer_w);
    client->height = rfbClientSwap16IfLE(msg.prsfb.buffer_h);
    client->updateRect.x = client->updateRect.y = 0;
    client->updateRect.w = client->width;
    client->updateRect.h = client->height;
    if (!client->MallocFrameBuffer(client))
      return FALSE;
    SendFramebufferUpdateRequest(client, 0, 0, client->width, client->height, FALSE);
    rfbClientLog("Got new framebuffer size: %dx%d\n", client->width, client->height);
    break;
  }

  default:
    {
      rfbBool handled = FALSE;
      rfbClientProtocolExtension* e;

      for(e = rfbClientExtensions; !handled && e; e = e->next)
	if(e->handleMessage && e->handleMessage(client, &msg))
	  handled = TRUE;

      if(!handled) {
	char buffer[256];
	rfbClientLog("Unknown message type %d from VNC server\n",msg.type);
	ReadFromRFBServer(client, buffer, 256);
	return FALSE;
      }
    }
  }

  return TRUE;
}

An issue was discovered in LibVNCServer before 0.9.13. libvncclient/rfbproto.c does not limit TextChat size.


Always correct the width and height of the image (#1859).

static MagickBooleanType ReadHEICImageByID(const ImageInfo *image_info,
  Image *image,struct heif_context *heif_context,heif_item_id image_id,
  ExceptionInfo *exception)
{
  const char
    *option;

  int
    stride_y,
    stride_cb,
    stride_cr;

  MagickBooleanType
    status;

  ssize_t
    y;

  struct heif_decoding_options
    *decode_options;

  struct heif_error
    error;

  struct heif_image
    *heif_image;

  struct heif_image_handle
    *image_handle;

  const uint8_t
    *p_y,
    *p_cb,
    *p_cr;

  error=heif_context_get_image_handle(heif_context,image_id,&image_handle);
  if (IsHeifSuccess(&error,image,exception) == MagickFalse)
    return(MagickFalse);
  if (ReadHEICColorProfile(image,image_handle,exception) == MagickFalse)
    {
      heif_image_handle_release(image_handle);
      return(MagickFalse);
    }
  if (ReadHEICExifProfile(image,image_handle,exception) == MagickFalse)
    {
      heif_image_handle_release(image_handle);
      return(MagickFalse);
    }
  /*
    Set image size.
  */
  image->depth=8;
  image->columns=(size_t) heif_image_handle_get_width(image_handle);
  image->rows=(size_t) heif_image_handle_get_height(image_handle);
  if (image_info->ping != MagickFalse)
    {
      image->colorspace=YCbCrColorspace;
      heif_image_handle_release(image_handle);
      return(MagickTrue);
    }
  if (HEICSkipImage(image_info,image) != MagickFalse)
    {
      heif_image_handle_release(image_handle);
      return(MagickTrue);
    }
  status=SetImageExtent(image,image->columns,image->rows,exception);
  if (status == MagickFalse)
    {
      heif_image_handle_release(image_handle);
      return(MagickFalse);
    }
  /*
    Copy HEIF image into ImageMagick data structures.
  */
  (void) SetImageColorspace(image,YCbCrColorspace,exception);
  decode_options=(struct heif_decoding_options *) NULL;
  option=GetImageOption(image_info,"heic:preserve-orientation");
  if (IsStringTrue(option) == MagickTrue)
    {
      decode_options=heif_decoding_options_alloc();
      decode_options->ignore_transformations=1;
    }
  else
    (void) SetImageProperty(image,"exif:Orientation","1",exception);
  error=heif_decode_image(image_handle,&heif_image,heif_colorspace_YCbCr,
    heif_chroma_420,decode_options);
  if (IsHeifSuccess(&error,image,exception) == MagickFalse)
    {
      heif_image_handle_release(image_handle);
      return(MagickFalse);
    }
  if (decode_options != (struct heif_decoding_options *) NULL)
    {
      /*
        Correct the width and height of the image.
      */
      image->columns=(size_t) heif_image_get_width(heif_image,heif_channel_Y);
      image->rows=(size_t) heif_image_get_height(heif_image,heif_channel_Y);
      status=SetImageExtent(image,image->columns,image->rows,exception);
      heif_decoding_options_free(decode_options);
      if (status == MagickFalse)
        {
          heif_image_release(heif_image);
          heif_image_handle_release(image_handle);
          return(MagickFalse);
        }
    }
  p_y=heif_image_get_plane_readonly(heif_image,heif_channel_Y,&stride_y);
  p_cb=heif_image_get_plane_readonly(heif_image,heif_channel_Cb,&stride_cb);
  p_cr=heif_image_get_plane_readonly(heif_image,heif_channel_Cr,&stride_cr);
  for (y=0; y < (ssize_t) image->rows; y++)
  {
    Quantum
      *q;

    register ssize_t
      x;

    q=QueueAuthenticPixels(image,0,y,image->columns,1,exception);
    if (q == (Quantum *) NULL)
      break;
    for (x=0; x < (ssize_t) image->columns; x++)
    {
      SetPixelRed(image,ScaleCharToQuantum((unsigned char) p_y[y*
        stride_y+x]),q);
      SetPixelGreen(image,ScaleCharToQuantum((unsigned char) p_cb[(y/2)*
        stride_cb+x/2]),q);
      SetPixelBlue(image,ScaleCharToQuantum((unsigned char) p_cr[(y/2)*
        stride_cr+x/2]),q);
      q+=GetPixelChannels(image);
    }
    if (SyncAuthenticPixels(image,exception) == MagickFalse)
      break;
  }
  heif_image_release(heif_image);
  heif_image_handle_release(image_handle);
  return(MagickTrue);
}

In ImageMagick 7.0.9, an out-of-bounds read vulnerability exists within the ReadHEICImageByID function in coders\heic.c. It can be triggered via an image with a width or height value that exceeds the actual size of the image.


Check the type of the field before performing the multiplication (details in #2132)

static MagickBooleanType TIFFGetProfiles(TIFF *tiff,Image *image,
  ExceptionInfo *exception)
{
  MagickBooleanType
    status;

  uint32
    length = 0;

  unsigned char
    *profile = (unsigned char *) NULL;

  status=MagickTrue;
#if defined(TIFFTAG_ICCPROFILE)
  if ((TIFFGetField(tiff,TIFFTAG_ICCPROFILE,&length,&profile) == 1) &&
      (profile != (unsigned char *) NULL))
    status=ReadProfile(image,"icc",profile,(ssize_t) length,exception);
#endif
#if defined(TIFFTAG_PHOTOSHOP)
  if ((TIFFGetField(tiff,TIFFTAG_PHOTOSHOP,&length,&profile) == 1) &&
      (profile != (unsigned char *) NULL))
    status=ReadProfile(image,"8bim",profile,(ssize_t) length,exception);
#endif
#if defined(TIFFTAG_RICHTIFFIPTC)
  if ((TIFFGetField(tiff,TIFFTAG_RICHTIFFIPTC,&length,&profile) == 1) &&
      (profile != (unsigned char *) NULL))
    {
      if (TIFFIsByteSwapped(tiff) != 0)
        TIFFSwabArrayOfLong((uint32 *) profile,(size_t) length);
      status=ReadProfile(image,"iptc",profile,4L*length,exception);
    }
#endif
#if defined(TIFFTAG_XMLPACKET)
  if ((TIFFGetField(tiff,TIFFTAG_XMLPACKET,&length,&profile) == 1) &&
      (profile != (unsigned char *) NULL))
    {
      StringInfo
        *dng;

      status=ReadProfile(image,"xmp",profile,(ssize_t) length,exception);
      dng=BlobToStringInfo(profile,length);
      if (dng != (StringInfo *) NULL)
        {
          const char
            *target = "dc:format=\"image/dng\"";

          if (strstr((char *) GetStringInfoDatum(dng),target) != (char *) NULL)
            (void) CopyMagickString(image->magick,"DNG",MagickPathExtent);
          dng=DestroyStringInfo(dng);
        }
    }
#endif
  if ((TIFFGetField(tiff,34118,&length,&profile) == 1) &&
      (profile != (unsigned char *) NULL))
    status=ReadProfile(image,"tiff:34118",profile,(ssize_t) length,
      exception);
  if ((TIFFGetField(tiff,37724,&length,&profile) == 1) &&
      (profile != (unsigned char *) NULL))
    status=ReadProfile(image,"tiff:37724",profile,(ssize_t) length,exception);
  return(status);
}

ImageMagick 7.0.9-27 through 7.0.10-17 has a heap-based buffer over-read in BlobToStringInfo in MagickCore/string.c during TIFF image decoding.


static CACHE_BITMAP_V3_ORDER* update_read_cache_bitmap_v3_order(rdpUpdate* update, wStream* s,
                                                                UINT16 flags)
{
	BYTE bitsPerPixelId;
	BITMAP_DATA_EX* bitmapData;
	UINT32 new_len;
	BYTE* new_data;
	CACHE_BITMAP_V3_ORDER* cache_bitmap_v3;

	if (!update || !s)
		return NULL;

	cache_bitmap_v3 = calloc(1, sizeof(CACHE_BITMAP_V3_ORDER));

	if (!cache_bitmap_v3)
		goto fail;

	cache_bitmap_v3->cacheId = flags & 0x00000003;
	cache_bitmap_v3->flags = (flags & 0x0000FF80) >> 7;
	bitsPerPixelId = (flags & 0x00000078) >> 3;
	cache_bitmap_v3->bpp = CBR23_BPP[bitsPerPixelId];

	if (Stream_GetRemainingLength(s) < 21)
		goto fail;

	Stream_Read_UINT16(s, cache_bitmap_v3->cacheIndex); /* cacheIndex (2 bytes) */
	Stream_Read_UINT32(s, cache_bitmap_v3->key1);       /* key1 (4 bytes) */
	Stream_Read_UINT32(s, cache_bitmap_v3->key2);       /* key2 (4 bytes) */
	bitmapData = &cache_bitmap_v3->bitmapData;
	Stream_Read_UINT8(s, bitmapData->bpp);

	if ((bitmapData->bpp < 1) || (bitmapData->bpp > 32))
	{
		WLog_Print(update->log, WLOG_ERROR, "invalid bpp value %" PRIu32 "", bitmapData->bpp);
		goto fail;
	}

	Stream_Seek_UINT8(s);                      /* reserved1 (1 byte) */
	Stream_Seek_UINT8(s);                      /* reserved2 (1 byte) */
	Stream_Read_UINT8(s, bitmapData->codecID); /* codecID (1 byte) */
	Stream_Read_UINT16(s, bitmapData->width);  /* width (2 bytes) */
	Stream_Read_UINT16(s, bitmapData->height); /* height (2 bytes) */
	Stream_Read_UINT32(s, new_len);            /* length (4 bytes) */

	if (Stream_GetRemainingLength(s) < new_len)
		goto fail;

	new_data = (BYTE*)realloc(bitmapData->data, new_len);

	if (!new_data)
		goto fail;

	bitmapData->data = new_data;
	bitmapData->length = new_len;
	Stream_Read(s, bitmapData->data, bitmapData->length);
	return cache_bitmap_v3;
fail:
	free_cache_bitmap_v3_order(update->context, cache_bitmap_v3);
	return NULL;
}

In FreeRDP greater than 1.2 and before 2.0.0, a double free in update_read_cache_bitmap_v3_order crashes the client application if corrupted data from a manipulated server is parsed. This has been patched in 2.0.0.