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| author | Noah Goldstein <goldstein.w.n@gmail.com> | 2022-09-20 17:58:04 -0700 |
|---|---|---|
| committer | Sunil K Pandey <skpgkp2@gmail.com> | 2022-11-24 10:40:09 -0800 |
| commit | fa196d06d392f9bb2eae2f41613c6b0710f26293 (patch) | |
| tree | a3ecf32ccf17270bd5456f82b6d8a195e7d586f2 /string | |
| parent | 2ba9801d9f222de9fe1f5f04dcd1c276e56b4245 (diff) | |
| download | glibc-fa196d06d392f9bb2eae2f41613c6b0710f26293.tar.gz glibc-fa196d06d392f9bb2eae2f41613c6b0710f26293.tar.xz glibc-fa196d06d392f9bb2eae2f41613c6b0710f26293.zip | |
x86: Fix wcsnlen-avx2 page cross length comparison [BZ #29591]
Previous implementation was adjusting length (rsi) to match bytes (eax), but since there is no bound to length this can cause overflow. Fix is to just convert the byte-count (eax) to length by dividing by sizeof (wchar_t) before the comparison. Full check passes on x86-64 and build succeeds w/ and w/o multiarch. (cherry picked from commit b0969fa53a28b4ab2159806bf6c99a98999502ee)
Diffstat (limited to 'string')
| -rw-r--r-- | string/test-strnlen.c | 70 |
1 files changed, 41 insertions, 29 deletions
diff --git a/string/test-strnlen.c b/string/test-strnlen.c index 4a9375112a..5cbaf4b734 100644 --- a/string/test-strnlen.c +++ b/string/test-strnlen.c @@ -73,7 +73,7 @@ do_test (size_t align, size_t len, size_t maxlen, int max_char) { size_t i; - align &= 63; + align &= (getpagesize () / sizeof (CHAR) - 1); if ((align + len) * sizeof (CHAR) >= page_size) return; @@ -90,38 +90,50 @@ do_test (size_t align, size_t len, size_t maxlen, int max_char) static void do_overflow_tests (void) { - size_t i, j, len; + size_t i, j, al_idx, repeats, len; const size_t one = 1; uintptr_t buf_addr = (uintptr_t) buf1; + const size_t alignments[] = { 0, 1, 7, 9, 31, 33, 63, 65, 95, 97, 127, 129 }; - for (i = 0; i < 750; ++i) + for (al_idx = 0; al_idx < sizeof (alignments) / sizeof (alignments[0]); + al_idx++) { - do_test (1, i, SIZE_MAX, BIG_CHAR); - - do_test (0, i, SIZE_MAX - i, BIG_CHAR); - do_test (0, i, i - buf_addr, BIG_CHAR); - do_test (0, i, -buf_addr - i, BIG_CHAR); - do_test (0, i, SIZE_MAX - buf_addr - i, BIG_CHAR); - do_test (0, i, SIZE_MAX - buf_addr + i, BIG_CHAR); - - len = 0; - for (j = 8 * sizeof(size_t) - 1; j ; --j) - { - len |= one << j; - do_test (0, i, len - i, BIG_CHAR); - do_test (0, i, len + i, BIG_CHAR); - do_test (0, i, len - buf_addr - i, BIG_CHAR); - do_test (0, i, len - buf_addr + i, BIG_CHAR); - - do_test (0, i, ~len - i, BIG_CHAR); - do_test (0, i, ~len + i, BIG_CHAR); - do_test (0, i, ~len - buf_addr - i, BIG_CHAR); - do_test (0, i, ~len - buf_addr + i, BIG_CHAR); - - do_test (0, i, -buf_addr, BIG_CHAR); - do_test (0, i, j - buf_addr, BIG_CHAR); - do_test (0, i, -buf_addr - j, BIG_CHAR); - } + for (repeats = 0; repeats < 2; ++repeats) + { + size_t align = repeats ? (getpagesize () - alignments[al_idx]) + : alignments[al_idx]; + align /= sizeof (CHAR); + for (i = 0; i < 750; ++i) + { + do_test (align, i, SIZE_MAX, BIG_CHAR); + + do_test (align, i, SIZE_MAX - i, BIG_CHAR); + do_test (align, i, i - buf_addr, BIG_CHAR); + do_test (align, i, -buf_addr - i, BIG_CHAR); + do_test (align, i, SIZE_MAX - buf_addr - i, BIG_CHAR); + do_test (align, i, SIZE_MAX - buf_addr + i, BIG_CHAR); + + len = 0; + for (j = 8 * sizeof (size_t) - 1; j; --j) + { + len |= one << j; + do_test (align, i, len, BIG_CHAR); + do_test (align, i, len - i, BIG_CHAR); + do_test (align, i, len + i, BIG_CHAR); + do_test (align, i, len - buf_addr - i, BIG_CHAR); + do_test (align, i, len - buf_addr + i, BIG_CHAR); + + do_test (align, i, ~len - i, BIG_CHAR); + do_test (align, i, ~len + i, BIG_CHAR); + do_test (align, i, ~len - buf_addr - i, BIG_CHAR); + do_test (align, i, ~len - buf_addr + i, BIG_CHAR); + + do_test (align, i, -buf_addr, BIG_CHAR); + do_test (align, i, j - buf_addr, BIG_CHAR); + do_test (align, i, -buf_addr - j, BIG_CHAR); + } + } + } } } |