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| author | Walter Lee <waltl@google.com> | 2017-11-16 17:03:00 +0000 |
|---|---|---|
| committer | Walter Lee <waltl@google.com> | 2017-11-16 17:03:00 +0000 |
| commit | 8f1545c629bbbc5beb5cf775ba8d1fd90dd5abe7 (patch) | |
| tree | 1d100f0747ea0092f764a3e7cad1a9e7eb742a25 /llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp | |
| parent | dcb9e1b387e4ceecf1a52ef0f7173f25dc5f9ca8 (diff) | |
| download | bcm5719-llvm-8f1545c629bbbc5beb5cf775ba8d1fd90dd5abe7.tar.gz bcm5719-llvm-8f1545c629bbbc5beb5cf775ba8d1fd90dd5abe7.zip | |
[asan] Fix small X86_64 ShadowOffset for non-default shadow scale
The requirement is that shadow memory must be aligned to page
boundaries (4k in this case). Use a closed form equation that always
satisfies this requirement.
Differential Revision: https://reviews.llvm.org/D39471
llvm-svn: 318421
Diffstat (limited to 'llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp')
| -rw-r--r-- | llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp | 16 |
1 files changed, 9 insertions, 7 deletions
diff --git a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp index 190efce225a..c707dfc0b50 100644 --- a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp +++ b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp @@ -97,7 +97,8 @@ static const uint64_t kDynamicShadowSentinel = static const uint64_t kIOSShadowOffset32 = 1ULL << 30; static const uint64_t kIOSSimShadowOffset32 = 1ULL << 30; static const uint64_t kIOSSimShadowOffset64 = kDefaultShadowOffset64; -static const uint64_t kSmallX86_64ShadowOffset = 0x7FFF8000; // < 2G. +static const uint64_t kSmallX86_64ShadowOffsetBase = 0x7FFFFFFF; // < 2G. +static const uint64_t kSmallX86_64ShadowOffsetAlignMask = ~0xFFFULL; static const uint64_t kLinuxKasan_ShadowOffset64 = 0xdffffc0000000000; static const uint64_t kPPC64_ShadowOffset64 = 1ULL << 41; static const uint64_t kSystemZ_ShadowOffset64 = 1ULL << 52; @@ -495,6 +496,11 @@ static ShadowMapping getShadowMapping(Triple &TargetTriple, int LongSize, ShadowMapping Mapping; + Mapping.Scale = kDefaultShadowScale; + if (ClMappingScale.getNumOccurrences() > 0) { + Mapping.Scale = ClMappingScale; + } + if (LongSize == 32) { if (IsAndroid) Mapping.Offset = kDynamicShadowSentinel; @@ -528,7 +534,8 @@ static ShadowMapping getShadowMapping(Triple &TargetTriple, int LongSize, if (IsKasan) Mapping.Offset = kLinuxKasan_ShadowOffset64; else - Mapping.Offset = kSmallX86_64ShadowOffset; + Mapping.Offset = (kSmallX86_64ShadowOffsetBase & + (kSmallX86_64ShadowOffsetAlignMask << Mapping.Scale)); } else if (IsWindows && IsX86_64) { Mapping.Offset = kWindowsShadowOffset64; } else if (IsMIPS64) @@ -548,11 +555,6 @@ static ShadowMapping getShadowMapping(Triple &TargetTriple, int LongSize, Mapping.Offset = kDynamicShadowSentinel; } - Mapping.Scale = kDefaultShadowScale; - if (ClMappingScale.getNumOccurrences() > 0) { - Mapping.Scale = ClMappingScale; - } - if (ClMappingOffset.getNumOccurrences() > 0) { Mapping.Offset = ClMappingOffset; } |
