redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

crypto: x86/sha256-avx - Fix RBP usage 

Using RBP as a temporary register breaks frame pointer convention and
breaks stack traces when unwinding from an interrupt in the crypto code.

Swap the usages of R12 and RBP.  Use R12 for the TBL register, and use
RBP to store the pre-aligned stack pointer.

Reported-by: Eric Biggers <ebiggers@google.com>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Tested-by: Eric Biggers <ebiggers@google.com>
Acked-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
hifive-unleashed-5.1
Josh Poimboeuf 2017-09-18 14:42:07 -05:00 committed by Herbert Xu
parent 6488bce756
commit 673ac6fbc7
1 changed files with 7 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
arch/x86/crypto/sha256-avx-asm.S
View File

@ -103,7 +103,7 @@ SRND = %rsi # clobbers INP
c = %ecx
d = %r8d
e = %edx
TBL = %rbp
TBL = %r12
a = %eax
b = %ebx
@ -350,13 +350,13 @@ a = TMP_
ENTRY(sha256_transform_avx)
.align 32
pushq %rbx
pushq %rbp
pushq %r12
pushq %r13
pushq %r14
pushq %r15
pushq %r12
pushq %rbp
movq %rsp, %rbp
mov %rsp, %r12
subq $STACK_SIZE, %rsp # allocate stack space
and $~15, %rsp # align stack pointer
@ -452,13 +452,12 @@ loop2:
done_hash:
mov %r12, %rsp
popq %r12
mov %rbp, %rsp
popq %rbp
popq %r15
popq %r14
popq %r13
popq %rbp
popq %r12
popq %rbx
ret
ENDPROC(sha256_transform_avx)