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author | Michael Matz <matz@suse.de> | 2012-04-05 10:48:14 +0200 |
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committer | Andreas Jaeger <aj@suse.de> | 2012-04-05 10:50:09 +0200 |
commit | e80d6f94e19d17b91e3cd3ada7193cc88f621feb (patch) | |
tree | f519a13feef74d70dfade10c595b72d3113add5f | |
parent | 349fa79f5527f78d60c78eb1fbb2dfb56846018c (diff) | |
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Fix size parameter comparisions.
[BZ #13592]
There are several signed compares of the size argument, whereas
it really is unsigned. Depending on situations e.g. a "memset(ptr, 0,
-1)" segfault (but for the wrong reasons, because jumping into nirvana)
or succeeds even.
In normal use this is harmless, as a size with signbit set indicates
more than half the address space which on x86_64 is impossible to
allocate, but as the size is used to index some jump tables this
potentially could have other unwanted side effects.
-rw-r--r-- | ChangeLog | 5 | ||||
-rw-r--r-- | NEWS | 10 | ||||
-rw-r--r-- | sysdeps/x86_64/memset.S | 12 |
3 files changed, 16 insertions, 11 deletions
@@ -1,3 +1,8 @@ +2012-04-05 Michael Matz <matz@suse.de> + + [BZ #13592] + * sysdeps/x86_64/memset.S: Fix size paramater comparisions. + 2012-04-05 Andreas Jaeger <aj@suse.de> [BZ #13908] @@ -15,11 +15,11 @@ Version 2.16 10110, 10135, 10140, 10210, 10346, 10545, 10716, 11174, 11322, 11365, 11451, 11494, 12047, 12340, 13058, 13525, 13526, 13527, 13528, 13529, 13530, 13531, 13532, 13533, 13547, 13551, 13552, 13553, 13555, 13559, - 13566, 13583, 13618, 13637, 13656, 13658, 13673, 13691, 13695, 13704, - 13706, 13726, 13738, 13760, 13761, 13786, 13792, 13806, 13824, 13840, - 13841, 13844, 13846, 13851, 13852, 13854, 13871, 13879, 13883, 13892, - 13908, 13910, 13911, 13912, 13913, 13915, 13916, 13917, 13918, 13919, - 13920, 13921, 13926, 13928, 13938 + 13566, 13583, 13592, 13618, 13637, 13656, 13658, 13673, 13691, 13695, + 13704, 13706, 13726, 13738, 13760, 13761, 13786, 13792, 13806, 13824, + 13840, 13841, 13844, 13846, 13851, 13852, 13854, 13871, 13879, 13883, + 13892, 13908, 13910, 13911, 13912, 13913, 13915, 13916, 13917, 13918, + 13919, 13920, 13921, 13926, 13928, 13938 * ISO C11 support: diff --git a/sysdeps/x86_64/memset.S b/sysdeps/x86_64/memset.S index 7be907192c..9511745a41 100644 --- a/sysdeps/x86_64/memset.S +++ b/sysdeps/x86_64/memset.S @@ -1,6 +1,6 @@ /* memset/bzero -- set memory area to CH/0 Optimized version for x86-64. - Copyright (C) 2002-2005, 2007, 2008, 2011 Free Software Foundation, Inc. + Copyright (C) 2002-2012 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or @@ -52,7 +52,7 @@ L(ck2): imul %r9,%rdx L(now_dw_aligned): cmp $0x90,%r8 - jg L(ck_mem_ops_method) + ja L(ck_mem_ops_method) L(now_dw_aligned_small): add %r8,%rdi #ifndef PIC @@ -604,7 +604,7 @@ L(aligned_now): punpcklqdq %xmm0,%xmm0 cmp $0xb0,%r8 # 176 - jge L(byte32sse2_pre) + jae L(byte32sse2_pre) add %r8,%rdi # ifndef PIC @@ -864,7 +864,7 @@ L(byte32sse2_pre): mov __x86_64_shared_cache_size(%rip),%r9d # The largest cache size cmp %r9,%r8 - jg L(sse2_nt_move_pre) + ja L(sse2_nt_move_pre) #jmp L(byte32sse2) .balign 16 L(byte32sse2): @@ -880,7 +880,7 @@ L(byte32sse2): movdqa %xmm0,0x70(%rdi) lea 0x80(%rdi),%rdi - jge L(byte32sse2) + jae L(byte32sse2) add %r8,%rdi # ifndef PIC lea L(SSExDx)(%rip),%r11 @@ -914,7 +914,7 @@ L(sse2_nt_move): movntdq %xmm0,0x70(%rdi) lea 0x80(%rdi),%rdi - jge L(sse2_nt_move) + jae L(sse2_nt_move) sfence add %r8,%rdi # ifndef PIC |