FAILED: patch "[PATCH] s390/crypto: Fix return code handling at skcipher_walk_done" failed to apply to 6.18-stable tree

PATCH [email protected] 1 participant 1 message Sep 16

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Stable branch Crypto API s390 s390 crypto modules, prng driver, arch random

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2026-09-16 16:07 UTC #0 lore raw

The patch below does not apply to the 6.18-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.18.y
git checkout FETCH_HEAD
git cherry-pick -x 403648373816ae8eb76fe4a393836b0d65fa8f85
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026091641-pushup-although-90f6@gregkh' --subject-prefix 'PATCH 6.18.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 403648373816ae8eb76fe4a393836b0d65fa8f85 Mon Sep 17 00:00:00 2001
From: Harald Freudenberger <[email protected]>
Date: Mon, 31 Aug 2026 10:38:30 +0200
Subject: [PATCH] s390/crypto: Fix return code handling at skcipher_walk_done
in PAES algorithms

All the 4 PAES cipher processing loops were not checking the return value of skcipher_walk_done() immediately after calling it. This could lead to error masking when both the walk operation failed and a subsequent key conversion was needed (k < n condition).

Add immediate error checks after skcipher_walk_done() in all main processing loops (ECB, CBC, CTR, XTS modes) to ensure walk errors are properly propagated and not masked by subsequent operations.

With that comes a slight rework around the skcipher_walk_done() invocation. It is now necessary to check if the walk has already been finalized (walk->nbytes is then 0) or not to avoid double de-allocation of resources held by the walk.

Fixes 6cd87cb5ef6c ("s390/crypto: Rework protected key AES for true asynch support")

Signed-off-by Harald Freudenberger <[email protected]>

Reviewed-by Holger Dengler <[email protected]>

Cc [email protected] # 6.16+

Signed-off-by Heiko Carstens <[email protected]>

Signed-off-by Vasily Gorbik <[email protected]>

arch/s390/crypto/paes_s390.c +27 ~~-11~~

index 973436592318..89785ab95e6b 100644
@@ -432,8 +432,11 @@ static int ecb_paes_do_crypt(struct s390_paes_ctx *ctx,
 		n = nbytes & ~(AES_BLOCK_SIZE - 1);
 		k = cpacf_km(ctx->fc | req_ctx->modifier, param,
 			     walk->dst.virt.addr, walk->src.virt.addr, n);
-		if (k)
+		if (k) {
 			rc = skcipher_walk_done(walk, nbytes - k);
+			if (rc)
+				goto out;
+		}
 		if (k < n) {
 			if (!maysleep) {
 				rc = -EKEYEXPIRED;

@@ -495,7 +498,7 @@ static int ecb_paes_crypt(struct skcipher_request *req, unsigned long modifier)
 			atomic_dec(&ctx->via_engine_ctr);
 	}
 
-	if (rc != -EINPROGRESS)
+	if (rc != -EINPROGRESS && walk->nbytes)
 		skcipher_walk_done(walk, rc);
 
 out:

@@ -549,7 +552,7 @@ static int ecb_paes_do_one_request(struct crypto_engine *engine, void *areq)
 	rc = ecb_paes_do_crypt(ctx, req_ctx, tested, true);
 	if (rc == -EKEYEXPIRED) {
 		return pkey_handle_expired();
-	} else if (rc) {
+	} else if (rc && walk->nbytes) {
 		skcipher_walk_done(walk, rc);
 	}

@@ -690,6 +693,8 @@ static int cbc_paes_do_crypt(struct s390_paes_ctx *ctx,
 		if (k) {
 			memcpy(walk->iv, param->iv, AES_BLOCK_SIZE);
 			rc = skcipher_walk_done(walk, nbytes - k);
+			if (rc)
+				goto out;
 		}
 		if (k < n) {
 			if (!maysleep) {

@@ -752,7 +757,7 @@ static int cbc_paes_crypt(struct skcipher_request *req, unsigned long modifier)
 			atomic_dec(&ctx->via_engine_ctr);
 	}
 
-	if (rc != -EINPROGRESS)
+	if (rc != -EINPROGRESS && walk->nbytes)
 		skcipher_walk_done(walk, rc);
 
 out:

@@ -806,7 +811,7 @@ static int cbc_paes_do_one_request(struct crypto_engine *engine, void *areq)
 	rc = cbc_paes_do_crypt(ctx, req_ctx, tested, true);
 	if (rc == -EKEYEXPIRED) {
 		return pkey_handle_expired();
-	} else if (rc) {
+	} else if (rc && walk->nbytes) {
 		skcipher_walk_done(walk, rc);
 	}

@@ -968,6 +973,11 @@ static int ctr_paes_do_crypt(struct s390_paes_ctx *ctx,
 				       AES_BLOCK_SIZE);
 			crypto_inc(walk->iv, AES_BLOCK_SIZE);
 			rc = skcipher_walk_done(walk, nbytes - k);
+			if (rc) {
+				if (locked)
+					mutex_unlock(&ctrblk_lock);
+				goto out;
+			}
 		}
 		if (k < n) {
 			if (!maysleep) {

@@ -1061,7 +1071,7 @@ static int ctr_paes_crypt(struct skcipher_request *req)
 			atomic_dec(&ctx->via_engine_ctr);
 	}
 
-	if (rc != -EINPROGRESS)
+	if (rc != -EINPROGRESS && walk->nbytes)
 		skcipher_walk_done(walk, rc);
 
 out:

@@ -1105,7 +1115,7 @@ static int ctr_paes_do_one_request(struct crypto_engine *engine, void *areq)
 	rc = ctr_paes_do_crypt(ctx, req_ctx, tested, true);
 	if (rc == -EKEYEXPIRED) {
 		return pkey_handle_expired();
-	} else if (rc) {
+	} else if (rc && walk->nbytes) {
 		skcipher_walk_done(walk, rc);
 	}

@@ -1283,8 +1293,11 @@ static int xts_paes_do_crypt_fullkey(struct s390_pxts_ctx *ctx,
 		n = nbytes & ~(AES_BLOCK_SIZE - 1);
 		k = cpacf_km(ctx->fc | req_ctx->modifier, param->key + offset,
 			     walk->dst.virt.addr, walk->src.virt.addr, n);
-		if (k)
+		if (k) {
 			rc = skcipher_walk_done(walk, nbytes - k);
+			if (rc)
+				goto out;
+		}
 		if (k < n) {
 			if (!maysleep) {
 				rc = -EKEYEXPIRED;

@@ -1377,8 +1390,11 @@ static int xts_paes_do_crypt_2keys(struct s390_pxts_ctx *ctx,
 		n = nbytes & ~(AES_BLOCK_SIZE - 1);
 		k = cpacf_km(ctx->fc | req_ctx->modifier, param->key + offset,
 			     walk->dst.virt.addr, walk->src.virt.addr, n);
-		if (k)
+		if (k) {
 			rc = skcipher_walk_done(walk, nbytes - k);
+			if (rc)
+				goto out;
+		}
 		if (k < n) {
 			if (!maysleep) {
 				rc = -EKEYEXPIRED;

@@ -1485,7 +1501,7 @@ static inline int xts_paes_crypt(struct skcipher_request *req, unsigned long mod
 			atomic_dec(&ctx->via_engine_ctr);
 	}
 
-	if (rc != -EINPROGRESS)
+	if (rc != -EINPROGRESS && walk->nbytes)
 		skcipher_walk_done(walk, rc);
 
 out:

@@ -1539,7 +1555,7 @@ static int xts_paes_do_one_request(struct crypto_engine *engine, void *areq)
 	rc = xts_paes_do_crypt(ctx, req_ctx, tested, true);
 	if (rc == -EKEYEXPIRED) {
 		return pkey_handle_expired();
-	} else if (rc) {
+	} else if (rc && walk->nbytes) {
 		skcipher_walk_done(walk, rc);
 	}