libbacktrace: fix UBSAN issues

Fix issues mentioned in the PR.

	PR libbacktrace/103167

libbacktrace/ChangeLog:

	* elf.c (elf_uncompress_lzma_block): Cast to unsigned int.
	(elf_uncompress_lzma): Likewise.
	* xztest.c (test_samples): memcpy only if v > 0.
This commit is contained in:
Martin Liska 2021-11-12 14:50:57 +01:00
parent aa1fd30df5
commit 83310a08a2
2 changed files with 17 additions and 17 deletions

View File

@ -3172,10 +3172,10 @@ elf_uncompress_lzma_block (const unsigned char *compressed,
/* Block header CRC. */
computed_crc = elf_crc32 (0, compressed + block_header_offset,
block_header_size - 4);
stream_crc = (compressed[off]
| (compressed[off + 1] << 8)
| (compressed[off + 2] << 16)
| (compressed[off + 3] << 24));
stream_crc = ((uint32_t)compressed[off]
| ((uint32_t)compressed[off + 1] << 8)
| ((uint32_t)compressed[off + 2] << 16)
| ((uint32_t)compressed[off + 3] << 24));
if (unlikely (computed_crc != stream_crc))
{
elf_uncompress_failed ();
@ -3785,10 +3785,10 @@ elf_uncompress_lzma (struct backtrace_state *state,
/* Next comes a CRC of the stream flags. */
computed_crc = elf_crc32 (0, compressed + 6, 2);
stream_crc = (compressed[8]
| (compressed[9] << 8)
| (compressed[10] << 16)
| (compressed[11] << 24));
stream_crc = ((uint32_t)compressed[8]
| ((uint32_t)compressed[9] << 8)
| ((uint32_t)compressed[10] << 16)
| ((uint32_t)compressed[11] << 24));
if (unlikely (computed_crc != stream_crc))
{
elf_uncompress_failed ();
@ -3829,10 +3829,10 @@ elf_uncompress_lzma (struct backtrace_state *state,
/* Before that is a footer CRC. */
computed_crc = elf_crc32 (0, compressed + offset, 6);
stream_crc = (compressed[offset - 4]
| (compressed[offset - 3] << 8)
| (compressed[offset - 2] << 16)
| (compressed[offset - 1] << 24));
stream_crc = ((uint32_t)compressed[offset - 4]
| ((uint32_t)compressed[offset - 3] << 8)
| ((uint32_t)compressed[offset - 2] << 16)
| ((uint32_t)compressed[offset - 1] << 24));
if (unlikely (computed_crc != stream_crc))
{
elf_uncompress_failed ();
@ -3888,10 +3888,10 @@ elf_uncompress_lzma (struct backtrace_state *state,
/* Next is a CRC of the index. */
computed_crc = elf_crc32 (0, compressed + index_offset,
offset - index_offset);
stream_crc = (compressed[offset]
| (compressed[offset + 1] << 8)
| (compressed[offset + 2] << 16)
| (compressed[offset + 3] << 24));
stream_crc = ((uint32_t)compressed[offset]
| ((uint32_t)compressed[offset + 1] << 8)
| ((uint32_t)compressed[offset + 2] << 16)
| ((uint32_t)compressed[offset + 3] << 24));
if (unlikely (computed_crc != stream_crc))
{
elf_uncompress_failed ();

View File

@ -172,7 +172,7 @@ test_samples (struct backtrace_state *state)
tests[i].name, uncompressed_len, v);
++failures;
}
else if (memcmp (tests[i].uncompressed, uncompressed, v) != 0)
else if (v > 0 && memcmp (tests[i].uncompressed, uncompressed, v) != 0)
{
size_t j;