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authorBorislav Petkov <[email protected]>2021-10-15 12:46:25 +0200
committerBorislav Petkov <[email protected]>2021-10-16 12:37:50 +0200
commitb2381acd3fd9bacd2c63f53b2c610c89959b31cc (patch)
tree06fa807068753d83013046b19d3a11f0f6450de9
parent711885906b5c2df90746a51f4cd674f1ab9fbb1d (diff)
x86/fpu: Mask out the invalid MXCSR bits properly
This is a fix for the fix (yeah, /facepalm). The correct mask to use is not the negation of the MXCSR_MASK but the actual mask which contains the supported bits in the MXCSR register. Reported and debugged by Ville Syrjälä <[email protected]> Fixes: d298b03506d3 ("x86/fpu: Restore the masking out of reserved MXCSR bits") Signed-off-by: Borislav Petkov <[email protected]> Tested-by: Ville Syrjälä <[email protected]> Tested-by: Ser Olmy <[email protected]> Cc: <[email protected]> Link: https://lore.kernel.org/r/[email protected]
-rw-r--r--arch/x86/kernel/fpu/signal.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/kernel/fpu/signal.c b/arch/x86/kernel/fpu/signal.c
index fa17a27390ab..831b25c5e705 100644
--- a/arch/x86/kernel/fpu/signal.c
+++ b/arch/x86/kernel/fpu/signal.c
@@ -385,7 +385,7 @@ static int __fpu_restore_sig(void __user *buf, void __user *buf_fx,
return -EINVAL;
} else {
/* Mask invalid bits out for historical reasons (broken hardware). */
- fpu->state.fxsave.mxcsr &= ~mxcsr_feature_mask;
+ fpu->state.fxsave.mxcsr &= mxcsr_feature_mask;
}
/* Enforce XFEATURE_MASK_FPSSE when XSAVE is enabled */