| Message ID | 1483455360-818-1-git-send-email-adhemerval.zanella@linaro.org |
|---|---|
| State | Accepted |
| Commit | 8dad72997af2be0dc72a4bc7dbe82d85c90334fc |
| Headers | show |
On Tuesday 03 January 2017 08:26 PM, Adhemerval Zanella wrote: > Similar to BZ#19387, BZ#21014, and BZ#20971, both x86 sse2 strncat > optimized assembly implementations do not handle the size overflow > correctly. > > The x86_64 one is in fact an issue with strcpy-sse2-unaligned, but > that is triggered also with strncat optimized implementation. > > This patch uses a similar strategy used on 3daef2c8ee4df2, where > saturared math is used for overflow case. > > Checked on x86_64-linux-gnu and i686-linux-gnu. > > [BZ #19390] > * string/test-strncat.c (test_main): Add tests with SIZE_MAX as > maximum string size. > * sysdeps/i386/i686/multiarch/strcat-sse2.S (STRCAT): Avoid overflow > in pointer addition. > * sysdeps/x86_64/multiarch/strcpy-sse2-unaligned.S (STRCPY): > Likewise. LGTM. Siddhesh
diff --git a/string/test-strncat.c b/string/test-strncat.c index 55d6cc5..26a6b5b 100644 --- a/string/test-strncat.c +++ b/string/test-strncat.c @@ -284,12 +284,23 @@ test_main (void) do_test (0, 0, 8, 8, n, SMALL_CHAR); do_test (0, 8, 8, 8, n, SMALL_CHAR); + do_test (0, 2, 2, 2, SIZE_MAX, SMALL_CHAR); + do_test (0, 0, 4, 4, SIZE_MAX, SMALL_CHAR); + do_test (4, 0, 4, 4, SIZE_MAX, BIG_CHAR); + do_test (0, 0, 8, 8, SIZE_MAX, SMALL_CHAR); + do_test (0, 8, 8, 8, SIZE_MAX, SMALL_CHAR); + for (i = 1; i < 8; ++i) { do_test (0, 0, 8 << i, 8 << i, n, SMALL_CHAR); do_test (8 - i, 2 * i, 8 << i, 8 << i, n, SMALL_CHAR); do_test (0, 0, 8 << i, 2 << i, n, SMALL_CHAR); do_test (8 - i, 2 * i, 8 << i, 2 << i, n, SMALL_CHAR); + + do_test (0, 0, 8 << i, 8 << i, SIZE_MAX, SMALL_CHAR); + do_test (8 - i, 2 * i, 8 << i, 8 << i, SIZE_MAX, SMALL_CHAR); + do_test (0, 0, 8 << i, 2 << i, SIZE_MAX, SMALL_CHAR); + do_test (8 - i, 2 * i, 8 << i, 2 << i, SIZE_MAX, SMALL_CHAR); } for (i = 1; i < 8; ++i) @@ -297,6 +308,10 @@ test_main (void) do_test (i, 2 * i, 8 << i, 1, n, SMALL_CHAR); do_test (2 * i, i, 8 << i, 1, n, BIG_CHAR); do_test (i, i, 8 << i, 10, n, SMALL_CHAR); + + do_test (i, 2 * i, 8 << i, 1, SIZE_MAX, SMALL_CHAR); + do_test (2 * i, i, 8 << i, 1, SIZE_MAX, BIG_CHAR); + do_test (i, i, 8 << i, 10, SIZE_MAX, SMALL_CHAR); } } diff --git a/sysdeps/i386/i686/multiarch/strcat-sse2.S b/sysdeps/i386/i686/multiarch/strcat-sse2.S index 145ae66..6359c73 100644 --- a/sysdeps/i386/i686/multiarch/strcat-sse2.S +++ b/sysdeps/i386/i686/multiarch/strcat-sse2.S @@ -227,6 +227,8 @@ L(StartStrcpyPart): pxor %xmm0, %xmm0 # ifdef USE_AS_STRNCAT add %ecx, %ebx + sbb %edx, %edx + or %edx, %ebx # endif sub %ecx, %eax jmp L(Unalign16Both) diff --git a/sysdeps/x86_64/multiarch/strcpy-sse2-unaligned.S b/sysdeps/x86_64/multiarch/strcpy-sse2-unaligned.S index c038043..6a5ab7a 100644 --- a/sysdeps/x86_64/multiarch/strcpy-sse2-unaligned.S +++ b/sysdeps/x86_64/multiarch/strcpy-sse2-unaligned.S @@ -99,6 +99,8 @@ L(Unalign16Both): sub %rcx, %rdi # ifdef USE_AS_STRNCPY add %rcx, %r8 + sbb %rcx, %rcx + or %rcx, %r8 # endif mov $16, %rcx movdqa (%rsi, %rcx), %xmm1