Reasoning:
The struct `VP8LBitWriter` in `src/utils/bit_writer_utils.h` uses
`buf`, `cur`, and `end` pointers to manage a dynamic buffer. Pointer
arithmetic on `buf` and `cur` caused bounds safety errors.
Initial attempts using `WEBP_ENDED_BY(end)` for both `buf` and `cur`
failed due to compiler limitations (one field cannot be the upper
bound for multiple other fields). Using `WEBP_INDEXABLE` for `buf` and
`cur` resolved the arithmetic errors but caused ABI incompatibility
issues, as `VP8LBitWriter` is used in multiple compilation units with
different settings.
The final approach annotates `buf` with `WEBP_ENDED_BY(end)` and `cur`
with `WEBP_UNSAFE_INDEXABLE`. This resolves the arithmetic errors for
both pointers without changing the ABI. `WEBP_UNSAFE_INDEXABLE` is
used for `cur` as a workaround for the `WEBP_ENDED_BY` limitation and
ABI constraints.
Additionally, the `VP8LBitWriterResize` function in
`src/utils/bit_writer_utils.c` was modified:
- The assignments to `bw->buf`, `bw->end`, and `bw->cur` (lines
231-233) were reordered and updated to use the local
`allocated_buf` variable on the right-hand side. This satisfies the
consecutive assignment requirement imposed by `WEBP_ENDED_BY(end)`
on `bw->buf`.
- The local variable `allocated_buf` (line 207) was annotated with
`WEBP_BIDI_INDEXABLE`.
- The allocation for `allocated_buf` (line 222) now uses
`WEBP_UNSAFE_FORGE_BIDI_INDEXABLE` to create a safe, bounded
pointer from the result of `WebPSafeMalloc`, fixing potential type
mismatches when `suppress_fbounds_errors=yes`.
Bug: 432511821
Change-Id: I603a6a7d3ff3bf2a8edf9749a9898ea227c32982
Import bounds_safety.h across all of webputils, with one exception being
dsp.h, since it's imported by webputils.h in one place. Also prepend
WEBP_ASSUME_UNSAFE_INDEXABLE_ABI to every webputil file to indicate to
the compiler that every pointer should be treated as __unsafe_indexable.
We also need to replace memcpy/memset/memmove with the unsafe variants
WEBP_UNSAFE_*, as memcpy/memset/memmove require bounded/sized pointers.
With this change, all of libwebputils (and libwebp) should build with
-DWEBP_ENABLE_FBOUNDS_SAFETY=true
Change-Id: Iad87be0455182d534c074ef6dc1a30fa66b74b6c
(Debian clang-format version 19.1.7 (3+build4)) with `--style=Google`.
Manual changes:
* clang-format disabled around macros with stringification (mostly
assembly)
* some inline assembly strings were adjusted to avoid awkward line
breaks
* trailing commas, `//` or suffixes (`ull`) added to help array
formatting
* thread_utils.c: parameter comments were changed to the more common
/*...=*/ style to improve formatting
The automatically generated code under swig/ was skipped.
Bug: 433996651
Change-Id: Iea3f24160d78d2a2653971cdf13fa932e47ff1b3
Semi-automatically taking the the misc-include-cleaner warnings
by clang-tidy and fixing files to be self-contained.
Change-Id: Iaaa2b2ec9d6dcce547fa5cb6b4f056dfc8c781ff
This is a follow up to:
ee8e8c62 Fix member naming for VP8LHistogram
This better matches Google style and clears some clang-tidy warnings.
This is the final change in this set. It is rather large due to the
shared dependencies between dec/enc.
Change-Id: I89de06b5653ae0bb627f904fa6060334831f7e3b
no change in object code
from clang-7 -fsanitize=implicit-integer-truncation
implicit conversion from type 'int32_t' (aka 'int') of value 287
(32-bit, signed) to type 'uint8_t' (aka 'unsigned char') changed the
value to 31 (8-bit, unsigned)
Change-Id: I692368bcc2f41412697b8ae51e53078831072891
dst->cur_ was not set.
The bug occurred only with several VP8LBitWriter instances
(thread_level > 0) and in 32-bit (in 64-bit, src->cur_ was
always 0 in VP8LBitWriterClone()).
BUG=chromium:917029
Change-Id: I0d94a3d8e62b247fd616eebe1009868dc8a5ed2e
When re-initializing a bit writer, we could set invalid values because
the bit writer was not big enough.
Change-Id: Id25ab6712603245a5a12d5f4a86fe35a9a799a5d
this avoids duplicates between these trees and dsp/, e.g., enc/tree.c,
dec/tree.c, making pulling the whole library source tree into one target
possible
BUG=webp:279
Change-Id: I060a614833c7c24ddd37bf641702ae6a5eef1775
