From 490fe3f05be3f7c87d7932bcb6e6e53e3db2cd9c Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Fri, 11 Jan 2008 08:09:35 +1100 Subject: [CRYPTO] padlock: Fix alignment fault in aes_crypt_copy The previous patch fixed spurious read faults from occuring by copying the data if we happen to have a single block at the end of a page. It appears that gcc cannot guarantee 16-byte alignment in the kernel with __attribute__. The following report from Torben Viets shows a buffer that's only 8-byte aligned: > eneral protection fault: 0000 [#1] > Modules linked in: xt_TCPMSS xt_tcpmss iptable_mangle ipt_MASQUERADE > xt_tcpudp xt_mark xt_state iptable_nat nf_nat nf_conntrack_ipv4 > iptable_filter ip_tables x_tables pppoe pppox af_packet ppp_generic slhc > aes_i586 > CPU: 0 > EIP: 0060:[] Not tainted VLI > EFLAGS: 00010292 (2.6.23.12 #7) > EIP is at aes_crypt_copy+0x28/0x40 > eax: f7639ff0 ebx: f6c24050 ecx: 00000001 edx: f6c24030 > esi: f7e89dc8 edi: f7639ff0 ebp: 00010000 esp: f7e89dc8 Since the hardware must have 16-byte alignment, the following patch fixes this by open coding the alignment adjustment. Signed-off-by: Herbert Xu --- drivers/crypto/padlock-aes.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/crypto') diff --git a/drivers/crypto/padlock-aes.c b/drivers/crypto/padlock-aes.c index a337b693b6c9..5f7e71810489 100644 --- a/drivers/crypto/padlock-aes.c +++ b/drivers/crypto/padlock-aes.c @@ -429,8 +429,8 @@ static inline void padlock_xcrypt(const u8 *input, u8 *output, void *key, static void aes_crypt_copy(const u8 *in, u8 *out, u32 *key, struct cword *cword) { - u8 tmp[AES_BLOCK_SIZE * 2] - __attribute__ ((__aligned__(PADLOCK_ALIGNMENT))); + u8 buf[AES_BLOCK_SIZE * 2 + PADLOCK_ALIGNMENT - 1]; + u8 *tmp = PTR_ALIGN(&buf[0], PADLOCK_ALIGNMENT); memcpy(tmp, in, AES_BLOCK_SIZE); padlock_xcrypt(tmp, out, key, cword); -- cgit v1.2.3-58-ga151