From 0beb34b865e37fee268fecbe17e37d1ce59b48ff Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Sun, 27 Jan 2019 10:16:52 +0100 Subject: [PATCH] crypto: arm/crct10dif - revert to C code for short inputs commit 62fecf295e3c48be1b5f17c440b93875b9adb4d6 upstream. The SIMD routine ported from x86 used to have a special code path for inputs < 16 bytes, which got lost somewhere along the way. Instead, the current glue code aligns the input pointer to permit the NEON routine to use special versions of the vld1 instructions that assume 16 byte alignment, but this could result in inputs of less than 16 bytes to be passed in. This not only fails the new extended tests that Eric has implemented, it also results in the code reading past the end of the input, which could potentially result in crashes when dealing with less than 16 bytes of input at the end of a page which is followed by an unmapped page. So update the glue code to only invoke the NEON routine if the input is at least 16 bytes. Reported-by: Eric Biggers Reviewed-by: Eric Biggers Fixes: 1d481f1cd892 ("crypto: arm/crct10dif - port x86 SSE implementation to ARM") Cc: # v4.10+ Signed-off-by: Ard Biesheuvel Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman --- arch/arm/crypto/crct10dif-ce-core.S | 14 +++++++------- arch/arm/crypto/crct10dif-ce-glue.c | 23 ++++++----------------- 2 files changed, 13 insertions(+), 24 deletions(-) diff --git a/arch/arm/crypto/crct10dif-ce-core.S b/arch/arm/crypto/crct10dif-ce-core.S index ce45ba0..16019b5 100644 --- a/arch/arm/crypto/crct10dif-ce-core.S +++ b/arch/arm/crypto/crct10dif-ce-core.S @@ -124,10 +124,10 @@ ENTRY(crc_t10dif_pmull) vext.8 q10, qzr, q0, #4 // receive the initial 64B data, xor the initial crc value - vld1.64 {q0-q1}, [arg2, :128]! - vld1.64 {q2-q3}, [arg2, :128]! - vld1.64 {q4-q5}, [arg2, :128]! - vld1.64 {q6-q7}, [arg2, :128]! + vld1.64 {q0-q1}, [arg2]! + vld1.64 {q2-q3}, [arg2]! + vld1.64 {q4-q5}, [arg2]! + vld1.64 {q6-q7}, [arg2]! CPU_LE( vrev64.8 q0, q0 ) CPU_LE( vrev64.8 q1, q1 ) CPU_LE( vrev64.8 q2, q2 ) @@ -167,7 +167,7 @@ CPU_LE( vrev64.8 q7, q7 ) _fold_64_B_loop: .macro fold64, reg1, reg2 - vld1.64 {q11-q12}, [arg2, :128]! + vld1.64 {q11-q12}, [arg2]! vmull.p64 q8, \reg1\()h, d21 vmull.p64 \reg1, \reg1\()l, d20 @@ -238,7 +238,7 @@ _16B_reduction_loop: vmull.p64 q7, d15, d21 veor.8 q7, q7, q8 - vld1.64 {q0}, [arg2, :128]! + vld1.64 {q0}, [arg2]! CPU_LE( vrev64.8 q0, q0 ) vswp d0, d1 veor.8 q7, q7, q0 @@ -335,7 +335,7 @@ _less_than_128: vmov.i8 q0, #0 vmov s3, arg1_low32 // get the initial crc value - vld1.64 {q7}, [arg2, :128]! + vld1.64 {q7}, [arg2]! CPU_LE( vrev64.8 q7, q7 ) vswp d14, d15 veor.8 q7, q7, q0 diff --git a/arch/arm/crypto/crct10dif-ce-glue.c b/arch/arm/crypto/crct10dif-ce-glue.c index d428355..14c19c7 100644 --- a/arch/arm/crypto/crct10dif-ce-glue.c +++ b/arch/arm/crypto/crct10dif-ce-glue.c @@ -35,26 +35,15 @@ static int crct10dif_update(struct shash_desc *desc, const u8 *data, unsigned int length) { u16 *crc = shash_desc_ctx(desc); - unsigned int l; - if (!may_use_simd()) { - *crc = crc_t10dif_generic(*crc, data, length); + if (length >= CRC_T10DIF_PMULL_CHUNK_SIZE && may_use_simd()) { + kernel_neon_begin(); + *crc = crc_t10dif_pmull(*crc, data, length); + kernel_neon_end(); } else { - if (unlikely((u32)data % CRC_T10DIF_PMULL_CHUNK_SIZE)) { - l = min_t(u32, length, CRC_T10DIF_PMULL_CHUNK_SIZE - - ((u32)data % CRC_T10DIF_PMULL_CHUNK_SIZE)); - - *crc = crc_t10dif_generic(*crc, data, l); - - length -= l; - data += l; - } - if (length > 0) { - kernel_neon_begin(); - *crc = crc_t10dif_pmull(*crc, data, length); - kernel_neon_end(); - } + *crc = crc_t10dif_generic(*crc, data, length); } + return 0; } -- 2.7.4