A-Team_Digital_Solutions/android_kernel_motorola_sm6375
Watch
2
0
Fork
You've already forked android_kernel_motorola_sm6375
 0
mirror of https://github.com/BobTheBlinker/android_kernel_motorola_sm6375.git synced 2026-10-06 11:54:14 -04:00
Code Issues Projects Releases Packages Wiki Activity

x86/cpu: Validate CPUID leaf 0x2 EDX output

Browse source 
commit 1881148215c67151b146450fb89ec22fd92337a7 upstream.

CPUID leaf 0x2 emits one-byte descriptors in its four output registers
EAX, EBX, ECX, and EDX.  For these descriptors to be valid, the most
significant bit (MSB) of each register must be clear.

Leaf 0x2 parsing at intel.c only validated the MSBs of EAX, EBX, and
ECX, but left EDX unchecked.

Validate EDX's most-significant bit as well.

Fixes: e0ba94f14f ("x86/tlb_info: get last level TLB entry number of CPU")
Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: stable@kernel.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20250304085152.51092-3-darwi@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Ahmed S. Darwish 2025-03-04 09:51:13 +01:00 • committed by Greg Kroah-Hartman
commit c67b103a8d
1 changed files with 1 additions and 1 deletions
Download patch file Download diff file Expand all files Collapse all files

2
arch/x86/kernel/cpu/intel.c
View file

@ -959,7 +959,7 @@ static void intel_detect_tlb(struct cpuinfo_x86 *c)
cpuid(2, &regs[0], &regs[1], &regs[2], &regs[3]);
/* If bit 31 is set, this is an unknown format */
for (j = 0 ; j < 3 ; j++)
for (j = 0 ; j < 4 ; j++)
if (regs[j] & (1 << 31))
regs[j] = 0;