From 15fa028589c3a2545f0bff355eff06d5844196bf Mon Sep 17 00:00:00 2001 From: Harald Freudenberger Date: Mon, 31 Aug 2026 10:37:33 +0200 Subject: [PATCH] s390/crypto: Fix skcipher_walk return code handling in aes_s390 The return codes from skcipher_walk_virt() were not properly checked before entering the processing loops in ecb_aes_crypt() and ctr_aes_crypt(). If skcipher_walk_virt() fails, the walk structure may be in an undefined state, and attempting to process data could lead to incorrect behavior or accessing uninitialized memory. Add proper return code checking to ensure correct handling of the walk initialization and walk advance and eventually return to the caller with that return code. Fixes: 7988fb2c03c8 ("crypto: s390/aes - convert to skcipher API") Signed-off-by: Harald Freudenberger Reviewed-by: Holger Dengler Cc: stable@vger.kernel.org # 5.5+ Signed-off-by: Heiko Carstens Signed-off-by: Vasily Gorbik --- arch/s390/crypto/aes_s390.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/arch/s390/crypto/aes_s390.c b/arch/s390/crypto/aes_s390.c index 62edc66d5478..366ce22d3623 100644 --- a/arch/s390/crypto/aes_s390.c +++ b/arch/s390/crypto/aes_s390.c @@ -129,7 +129,7 @@ static int ecb_aes_crypt(struct skcipher_request *req, unsigned long modifier) return fallback_skcipher_crypt(sctx, req, modifier); ret = skcipher_walk_virt(&walk, req, false); - while ((nbytes = walk.nbytes) != 0) { + while (!ret && ((nbytes = walk.nbytes) != 0)) { /* only use complete blocks */ n = nbytes & ~(AES_BLOCK_SIZE - 1); cpacf_km(sctx->fc | modifier, sctx->key, @@ -233,7 +233,7 @@ static int cbc_aes_crypt(struct skcipher_request *req, unsigned long modifier) return ret; memcpy(param.iv, walk.iv, AES_BLOCK_SIZE); memcpy(param.key, sctx->key, sctx->key_len); - while ((nbytes = walk.nbytes) != 0) { + while (!ret && ((nbytes = walk.nbytes) != 0)) { /* only use complete blocks */ n = nbytes & ~(AES_BLOCK_SIZE - 1); cpacf_kmc(sctx->fc | modifier, ¶m, @@ -359,7 +359,7 @@ static int xts_aes_crypt(struct skcipher_request *req, unsigned long modifier) memcpy(xts_param.key + offset, xts_ctx->key, xts_ctx->key_len); memcpy(xts_param.init, pcc_param.xts, 16); - while ((nbytes = walk.nbytes) != 0) { + while (!ret && ((nbytes = walk.nbytes) != 0)) { /* only use complete blocks */ n = nbytes & ~(AES_BLOCK_SIZE - 1); cpacf_km(xts_ctx->fc | modifier, xts_param.key + offset, @@ -487,7 +487,7 @@ static int fullxts_aes_crypt(struct skcipher_request *req, unsigned long modifi memcpy(fxts_param.tweak, req->iv, AES_BLOCK_SIZE); fxts_param.nap[0] = 0x01; /* initial alpha power (1, little-endian) */ - while ((nbytes = walk.nbytes) != 0) { + while (!ret && ((nbytes = walk.nbytes) != 0)) { /* only use complete blocks */ n = nbytes & ~(AES_BLOCK_SIZE - 1); cpacf_km(xts_ctx->fc | modifier, fxts_param.key + offset, @@ -577,7 +577,7 @@ static int ctr_aes_crypt(struct skcipher_request *req) locked = mutex_trylock(&ctrblk_lock); ret = skcipher_walk_virt(&walk, req, false); - while ((nbytes = walk.nbytes) >= AES_BLOCK_SIZE) { + while (!ret && ((nbytes = walk.nbytes) >= AES_BLOCK_SIZE)) { n = AES_BLOCK_SIZE; if (nbytes >= 2*AES_BLOCK_SIZE && locked) @@ -596,7 +596,7 @@ static int ctr_aes_crypt(struct skcipher_request *req) /* * final block may be < AES_BLOCK_SIZE, copy only nbytes */ - if (nbytes) { + if (!ret && nbytes) { memset(buf, 0, AES_BLOCK_SIZE); memcpy(buf, walk.src.virt.addr, nbytes); cpacf_kmctr(sctx->fc, sctx->key, buf, buf,