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FAILED: patch "[PATCH] crypto: qat - validate RSA CRT component lengths" failed to apply to 5.10-stable tree

PATCH New [email protected] 2 participants 2 messages Jul 15 – Jul 21

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Stable branch Crypto API QAT driver
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author maintainer
#0 lore raw

The patch below does not apply to the 5.10-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-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x b3ac78756588059729b9195fcc9f4b37d54057a5
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026071550-slacking-pants-3db9@gregkh' --subject-prefix 'PATCH 5.10.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

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

From b3ac78756588059729b9195fcc9f4b37d54057a5 Mon Sep 17 00:00:00 2001
From: Giovanni Cabiddu <[email protected]>
Date: Thu, 28 May 2026 16:57:44 +0100
Subject: [PATCH] crypto: qat - validate RSA CRT component lengths

The generic RSA key parser (rsa_helper.c) bounds each CRT component (p, q, dp, dq, qinv) by the modulus size n_sz, but qat_rsa_setkey_crt() allocates half-size DMA buffers (key_sz / 2) and right-aligns each component with:

memcpy(dst + half_key_sz - len, src, len)

When a CRT component is larger than half_key_sz the subtraction underflows and memcpy writes past the DMA buffer, causing memory corruption.

Add a len > half_key_sz check next to the existing !len check for each of the five CRT components so the driver falls back to the non-CRT path instead of writing out of bounds.

Fixes 879f77e9071f ("crypto: qat - Add RSA CRT mode")
Cc [email protected]
Signed-off-by Giovanni Cabiddu <[email protected]>
Reviewed-by Ahsan Atta <[email protected]>
Reviewed-by Laurent M Coquerel <[email protected]>
Tested-by Laurent M Coquerel <[email protected]>
Signed-off-by Herbert Xu <[email protected]>
drivers/crypto/intel/qat/qat_common/qat_asym_algs.c +5 -5
index e09b9edfce42..75c15c8e41db 100644
@@ -1085,7 +1085,7 @@ static void qat_rsa_setkey_crt(struct qat_rsa_ctx *ctx, struct rsa_key *rsa_key)
 	ptr = rsa_key->p;
 	len = rsa_key->p_sz;
 	qat_rsa_drop_leading_zeros(&ptr, &len);
-	if (!len)
+	if (!len || len > half_key_sz)
 		goto err;
 	ctx->p = dma_alloc_coherent(dev, half_key_sz, &ctx->dma_p, GFP_KERNEL);
 	if (!ctx->p)

@@ -1096,7 +1096,7 @@ static void qat_rsa_setkey_crt(struct qat_rsa_ctx *ctx, struct rsa_key *rsa_key)
 	ptr = rsa_key->q;
 	len = rsa_key->q_sz;
 	qat_rsa_drop_leading_zeros(&ptr, &len);
-	if (!len)
+	if (!len || len > half_key_sz)
 		goto free_p;
 	ctx->q = dma_alloc_coherent(dev, half_key_sz, &ctx->dma_q, GFP_KERNEL);
 	if (!ctx->q)

@@ -1107,7 +1107,7 @@ static void qat_rsa_setkey_crt(struct qat_rsa_ctx *ctx, struct rsa_key *rsa_key)
 	ptr = rsa_key->dp;
 	len = rsa_key->dp_sz;
 	qat_rsa_drop_leading_zeros(&ptr, &len);
-	if (!len)
+	if (!len || len > half_key_sz)
 		goto free_q;
 	ctx->dp = dma_alloc_coherent(dev, half_key_sz, &ctx->dma_dp,
 				     GFP_KERNEL);

@@ -1119,7 +1119,7 @@ static void qat_rsa_setkey_crt(struct qat_rsa_ctx *ctx, struct rsa_key *rsa_key)
 	ptr = rsa_key->dq;
 	len = rsa_key->dq_sz;
 	qat_rsa_drop_leading_zeros(&ptr, &len);
-	if (!len)
+	if (!len || len > half_key_sz)
 		goto free_dp;
 	ctx->dq = dma_alloc_coherent(dev, half_key_sz, &ctx->dma_dq,
 				     GFP_KERNEL);

@@ -1131,7 +1131,7 @@ static void qat_rsa_setkey_crt(struct qat_rsa_ctx *ctx, struct rsa_key *rsa_key)
 	ptr = rsa_key->qinv;
 	len = rsa_key->qinv_sz;
 	qat_rsa_drop_leading_zeros(&ptr, &len);
-	if (!len)
+	if (!len || len > half_key_sz)
 		goto free_dq;
 	ctx->qinv = dma_alloc_coherent(dev, half_key_sz, &ctx->dma_qinv,
 				       GFP_KERNEL);
maintainer
#1 lore raw

PATCH 1/1 crypto: qat - validate RSA CRT component lengths

From: Giovanni Cabiddu <[email protected]>

[ Upstream commit b3ac78756588059729b9195fcc9f4b37d54057a5 ]

The generic RSA key parser (rsa_helper.c) bounds each CRT component (p, q, dp, dq, qinv) by the modulus size n_sz, but qat_rsa_setkey_crt() allocates half-size DMA buffers (key_sz / 2) and right-aligns each component with:

memcpy(dst + half_key_sz - len, src, len)

When a CRT component is larger than half_key_sz the subtraction underflows and memcpy writes past the DMA buffer, causing memory corruption.

Add a len > half_key_sz check next to the existing !len check for each of the five CRT components so the driver falls back to the non-CRT path instead of writing out of bounds.

Fixes 879f77e9071f ("crypto: qat - Add RSA CRT mode")
Cc [email protected]
Signed-off-by Giovanni Cabiddu <[email protected]>
Reviewed-by Ahsan Atta <[email protected]>
Reviewed-by Laurent M Coquerel <[email protected]>
Tested-by Laurent M Coquerel <[email protected]>
Signed-off-by Herbert Xu <[email protected]>
Signed-off-by Sasha Levin <[email protected]>
---
 drivers/crypto/qat/qat_common/qat_asym_algs.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)
drivers/crypto/qat/qat_common/qat_asym_algs.c +5 -5
index 846569ec906653..63e55698384559 100644
@@ -1030,7 +1030,7 @@ static void qat_rsa_setkey_crt(struct qat_rsa_ctx *ctx, struct rsa_key *rsa_key)
 	ptr = rsa_key->p;
 	len = rsa_key->p_sz;
 	qat_rsa_drop_leading_zeros(&ptr, &len);
-	if (!len)
+	if (!len || len > half_key_sz)
 		goto err;
 	ctx->p = dma_alloc_coherent(dev, half_key_sz, &ctx->dma_p, GFP_KERNEL);
 	if (!ctx->p)

@@ -1041,7 +1041,7 @@ static void qat_rsa_setkey_crt(struct qat_rsa_ctx *ctx, struct rsa_key *rsa_key)
 	ptr = rsa_key->q;
 	len = rsa_key->q_sz;
 	qat_rsa_drop_leading_zeros(&ptr, &len);
-	if (!len)
+	if (!len || len > half_key_sz)
 		goto free_p;
 	ctx->q = dma_alloc_coherent(dev, half_key_sz, &ctx->dma_q, GFP_KERNEL);
 	if (!ctx->q)

@@ -1052,7 +1052,7 @@ static void qat_rsa_setkey_crt(struct qat_rsa_ctx *ctx, struct rsa_key *rsa_key)
 	ptr = rsa_key->dp;
 	len = rsa_key->dp_sz;
 	qat_rsa_drop_leading_zeros(&ptr, &len);
-	if (!len)
+	if (!len || len > half_key_sz)
 		goto free_q;
 	ctx->dp = dma_alloc_coherent(dev, half_key_sz, &ctx->dma_dp,
 				     GFP_KERNEL);

@@ -1064,7 +1064,7 @@ static void qat_rsa_setkey_crt(struct qat_rsa_ctx *ctx, struct rsa_key *rsa_key)
 	ptr = rsa_key->dq;
 	len = rsa_key->dq_sz;
 	qat_rsa_drop_leading_zeros(&ptr, &len);
-	if (!len)
+	if (!len || len > half_key_sz)
 		goto free_dp;
 	ctx->dq = dma_alloc_coherent(dev, half_key_sz, &ctx->dma_dq,
 				     GFP_KERNEL);

@@ -1076,7 +1076,7 @@ static void qat_rsa_setkey_crt(struct qat_rsa_ctx *ctx, struct rsa_key *rsa_key)
 	ptr = rsa_key->qinv;
 	len = rsa_key->qinv_sz;
 	qat_rsa_drop_leading_zeros(&ptr, &len);
-	if (!len)
+	if (!len || len > half_key_sz)
 		goto free_dq;
 	ctx->qinv = dma_alloc_coherent(dev, half_key_sz, &ctx->dma_qinv,
 				       GFP_KERNEL);
Signature · 1 line
2.53.0