The check `src > dst' in the form `&c->out[-back] > c->out' invokes
pointer overflow, which is undefined behavior in C.
Remove the check. Also replace `&c->out[-back] < c->out_start' with
a safe form `c->out - c->out_start < back' to avoid overflow.
CC: libav-stable@libav.org
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
Simplify `p->buf > p->buf + p->buf_size - 4' as `p->buf_size < 4'.
Avoid a possible out-of-bounds pointer, which is undefined behavior
in C.
CC: libav-stable@libav.org
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
When `off' is 0, `0x537F6103 << 32' in the following expression invokes
undefined behavior, the result of which is not necessarily 0.
(0x537F6103 >> (off * 8)) | (0x537F6103 << (32 - (off * 8)))
Avoid oversized shifting.
CC: libav-stable@libav.org
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
The check `start + res < start' is broken since pointer overflow is
undefined behavior in C. Many compilers such as gcc/clang optimize
away this check.
Use `res > end - start' instead. Also change `res' to unsigned int
to avoid signed left-shift overflow.
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Martin Storsjö <martin@martin.st>
A negative `size' will bypass FFMIN(). In the subsequent memcpy() call,
`size' will be considered as a large positive value, leading to a buffer
overflow.
Change the type of `size' to unsigned int to avoid buffer overflow, and
simplify overflow checks accordingly. Also change a literal buffer
size to use sizeof, and limit the amount of data copied in another
memcpy call as well.
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Martin Storsjö <martin@martin.st>
Sanity checks like `data + size >= data_end || data + size < data' are
broken, because `data + size < data' assumes pointer overflow, which is
undefined behavior in C. Many compilers such as gcc/clang optimize such
checks away.
Use `size < 0 || size >= data_end - data' instead.
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Martin Storsjö <martin@martin.st>
The loop condition `x = ex' is incorrect. It should be `x <= ex'.
This bug was introduced in commit c65dfac4 "mpegvideo.c: K&R formatting
and cosmetics."
CC:libav-stable@libav.org
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
sws_getCachedContext() and sws_getContext() expect sws_alloc_context()
to return NULL when out of memory, as follows.
if (!(context = sws_alloc_context()))
return NULL;
This patch fixes sws_alloc_context() to return NULL in that case.
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
The following out-of-memory check is broken.
*sorted_segments = av_mallocz(...);
if (!sorted_segments) { ... }
The correct NULL check should use *sorted_segments.
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
The vertical offset mask 0x07 is suspicious.
v_off = FFMIN(data[2] & 0x07, CDG_BORDER_HEIGHT - 1);
Note that v_off is up to 11 (CDG_BORDER_HEIGHT - 1), the correct mask
should be 0x0F.
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Anton Khirnov <anton@khirnov.net>
The following error handling is broken due to signedness.
int file_size;
uint32_t tag_bytes;
int64_t tag_start;
...
tag_start = file_size - tag_bytes - APE_TAG_FOOTER_BYTES;
if (tag_start < 0) { ... }
Note that tag_bytes is unsigned, which makes the right-hand side of
`tag_start = ...' unsigned, too. The 32-bit unsigned value is then
zero-extended to 64 bits. Therefore, tag_start must be non-negative,
and the check (tag_start < 0) is always false, which breaks the error
handling. This patch fixes the check.
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Anton Khirnov <anton@khirnov.net>
Since the pointer `oc' is NULL, oc->oformat->name will cause a null
pointer dereference. This patch changes it to seg->oformat->name.
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Martin Storsjö <martin@martin.st>
Xi WangandLuca Barbato
