crypto: x86/twofish - 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.

Use R13 instead of RBP.  Both are callee-saved registers, so the
substitution is straightforward.

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>
This commit is contained in:
Josh Poimboeuf 2017-09-18 14:42:11 -05:00 committed by Herbert Xu
parent ca04c82376
commit 8f182f845d

View File

@ -76,8 +76,8 @@
#define RT %xmm14
#define RR %xmm15
#define RID1 %rbp
#define RID1d %ebp
#define RID1 %r13
#define RID1d %r13d
#define RID2 %rsi
#define RID2d %esi
@ -259,7 +259,7 @@ __twofish_enc_blk8:
vmovdqu w(CTX), RK1;
pushq %rbp;
pushq %r13;
pushq %rbx;
pushq %rcx;
@ -282,7 +282,7 @@ __twofish_enc_blk8:
popq %rcx;
popq %rbx;
popq %rbp;
popq %r13;
outunpack_blocks(RC1, RD1, RA1, RB1, RK1, RX0, RY0, RK2);
outunpack_blocks(RC2, RD2, RA2, RB2, RK1, RX0, RY0, RK2);
@ -301,7 +301,7 @@ __twofish_dec_blk8:
vmovdqu (w+4*4)(CTX), RK1;
pushq %rbp;
pushq %r13;
pushq %rbx;
inpack_blocks(RC1, RD1, RA1, RB1, RK1, RX0, RY0, RK2);
@ -322,7 +322,7 @@ __twofish_dec_blk8:
vmovdqu (w)(CTX), RK1;
popq %rbx;
popq %rbp;
popq %r13;
outunpack_blocks(RA1, RB1, RC1, RD1, RK1, RX0, RY0, RK2);
outunpack_blocks(RA2, RB2, RC2, RD2, RK1, RX0, RY0, RK2);