[PATCH 4.4 101/117] crypto: chacha20-ssse3 - Align stack pointer to 64 bytes

Greg Kroah-Hartman
2016-02-15T00:22:55Z

From: Eli Cooper <elicooper@gmx.com>

commit cbe09bd51bf23b42c3a94c5fb6815e1397c5fc3f upstream.

This aligns the stack pointer in chacha20_4block_xor_ssse3 to 64 bytes.
Fixes general protection faults and potential kernel panics.

Signed-off-by: Eli Cooper <elicooper@gmx.com>
Acked-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/x86/crypto/chacha20-ssse3-x86_64.S | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

--- a/arch/x86/crypto/chacha20-ssse3-x86_64.S
+++ b/arch/x86/crypto/chacha20-ssse3-x86_64.S
@@ -157,7 +157,9 @@ ENTRY(chacha20_4block_xor_ssse3)
# done with the slightly better performing SSSE3 byte shuffling,
# 7/12-bit word rotation uses traditional shift+OR.

- sub $0x40,%rsp
+ mov %rsp,%r11
+ sub $0x80,%rsp
+ and $~63,%rsp

# x0..15[0-3] = s0..3[0..3]
movq 0x00(%rdi),%xmm1
@@ -620,6 +622,6 @@ ENTRY(chacha20_4block_xor_ssse3)
pxor %xmm1,%xmm15
movdqu %xmm15,0xf0(%rsi)

- add $0x40,%rsp
+ mov %r11,%rsp
ret
ENDPROC(chacha20_4block_xor_ssse3)