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author | Borislav Petkov (AMD) <bp@alien8.de> | 2023-08-05 01:06:43 +0300 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2023-08-09 17:55:00 +0300 |
commit | 77245f1c3c6495521f6a3af082696ee2f8ce3921 (patch) | |
tree | fca77ee5bfe3c557f190f201e39a82688f9ac9b4 /arch/x86/include/asm/cpufeatures.h | |
parent | 13b9372068660fe4f7023f43081067376582ef3c (diff) | |
download | linux-77245f1c3c6495521f6a3af082696ee2f8ce3921.tar.xz |
x86/CPU/AMD: Do not leak quotient data after a division by 0
Under certain circumstances, an integer division by 0 which faults, can
leave stale quotient data from a previous division operation on Zen1
microarchitectures.
Do a dummy division 0/1 before returning from the #DE exception handler
in order to avoid any leaks of potentially sensitive data.
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: <stable@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'arch/x86/include/asm/cpufeatures.h')
-rw-r--r-- | arch/x86/include/asm/cpufeatures.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h index 094f88fee536..b69b0d7756aa 100644 --- a/arch/x86/include/asm/cpufeatures.h +++ b/arch/x86/include/asm/cpufeatures.h @@ -495,4 +495,5 @@ /* BUG word 2 */ #define X86_BUG_SRSO X86_BUG(1*32 + 0) /* AMD SRSO bug */ +#define X86_BUG_DIV0 X86_BUG(1*32 + 1) /* AMD DIV0 speculation bug */ #endif /* _ASM_X86_CPUFEATURES_H */ |