FAILED: patch "[PATCH] rxrpc: Also unshare DATA/RESPONSE packets when paged frags" failed to apply to 6.12-stable tree

FAILED: patch "[PATCH] rxrpc: Also unshare DATA/RESPONSE packets when paged frags" failed to apply to 6.12-stable tree

[gregkh]

The patch below does not apply to the 6.12-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 <stable@vger.kernel.org>.

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-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x aa54b1d27fe0c2b78e664a34fd0fdf7cd1960d71
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026051109-ocelot-dwindle-a7e9@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

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

From aa54b1d27fe0c2b78e664a34fd0fdf7cd1960d71 Mon Sep 17 00:00:00 2001
From: Hyunwoo Kim <imv4bel@gmail.com>
Date: Fri, 8 May 2026 17:53:09 +0900
Subject: [PATCH] rxrpc: Also unshare DATA/RESPONSE packets when paged frags
 are present

The DATA-packet handler in rxrpc_input_call_event() and the RESPONSE
handler in rxrpc_verify_response() copy the skb to a linear one before
calling into the security ops only when skb_cloned() is true.  An skb
that is not cloned but still carries externally-owned paged fragments
(e.g. SKBFL_SHARED_FRAG set by splice() into a UDP socket via
__ip_append_data, or a chained skb_has_frag_list()) falls through to
the in-place decryption path, which binds the frag pages directly into
the AEAD/skcipher SGL via skb_to_sgvec().

Extend the gate to also unshare when skb_has_frag_list() or
skb_has_shared_frag() is true.  This catches the splice-loopback vector
and other externally-shared frag sources while preserving the
zero-copy fast path for skbs whose frags are kernel-private (e.g. NIC
page_pool RX, GRO).  The OOM/trace handling already in place is reused.

Fixes: d0d5c0cd1e71 ("rxrpc: Use skb_unshare() rather than skb_cow_data()")
Cc: stable@vger.kernel.org
Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com>
Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/net/rxrpc/call_event.c b/net/rxrpc/call_event.c
index fdd683261226..2b19b252225e 100644
--- a/net/rxrpc/call_event.c
+++ b/net/rxrpc/call_event.c
@@ -334,7 +334,9 @@ bool rxrpc_input_call_event(struct rxrpc_call *call)
 
 			if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA &&
 			    sp->hdr.securityIndex != 0 &&
-			    skb_cloned(skb)) {
+			    (skb_cloned(skb) ||
+			     skb_has_frag_list(skb) ||
+			     skb_has_shared_frag(skb))) {
 				/* Unshare the packet so that it can be
 				 * modified by in-place decryption.
 				 */
diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c
index a2130d25aaa9..442414d90ba1 100644
--- a/net/rxrpc/conn_event.c
+++ b/net/rxrpc/conn_event.c
@@ -245,7 +245,8 @@ static int rxrpc_verify_response(struct rxrpc_connection *conn,
 {
 	int ret;
 
-	if (skb_cloned(skb)) {
+	if (skb_cloned(skb) || skb_has_frag_list(skb) ||
+	    skb_has_shared_frag(skb)) {
 		/* Copy the packet if shared so that we can do in-place
 		 * decryption.
 		 */

[PATCH 1/2] rxrpc: Fix conn-level packet handling to unshare RESPONSE packets

[Wentao Guan]

From: David Howells <dhowells@redhat.com>

The security operations that verify the RESPONSE packets decrypt bits of it
in place - however, the sk_buff may be shared with a packet sniffer, which
would lead to the sniffer seeing an apparently corrupt packet (actually
decrypted).

Fix this by handing a copy of the packet off to the specific security
handler if the packet was cloned.

Fixes: 17926a79320a ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both")
Closes: https://sashiko.dev/#/patchset/20260408121252.2249051-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Jeffrey Altman <jaltman@auristor.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
Link: https://patch.msgid.link/20260422161438.2593376-5-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
(cherry picked from commit 24481a7f573305706054c59e275371f8d0fe919f)
Stable-dep-of: aa54b1d27fe0 ("rxrpc: Also unshare DATA/RESPONSE packets when
paged frags are present")
Signed-off-by: Wentao Guan <guanwentao@uniontech.com>
---
 net/rxrpc/conn_event.c | 29 ++++++++++++++++++++++++++++-
 1 file changed, 28 insertions(+), 1 deletion(-)

diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c
index 82cc72123c9c9..6dcfaed1f7485 100644
--- a/net/rxrpc/conn_event.c
+++ b/net/rxrpc/conn_event.c
@@ -226,6 +226,33 @@ static void rxrpc_call_is_secure(struct rxrpc_call *call)
 		rxrpc_notify_socket(call);
 }
 
+static int rxrpc_verify_response(struct rxrpc_connection *conn,
+				 struct sk_buff *skb)
+{
+	int ret;
+
+	if (skb_cloned(skb)) {
+		/* Copy the packet if shared so that we can do in-place
+		 * decryption.
+		 */
+		struct sk_buff *nskb = skb_copy(skb, GFP_NOFS);
+
+		if (nskb) {
+			rxrpc_new_skb(nskb, rxrpc_skb_new_unshared);
+			ret = conn->security->verify_response(conn, nskb);
+			rxrpc_free_skb(nskb, rxrpc_skb_put_response_copy);
+		} else {
+			/* OOM - Drop the packet. */
+			rxrpc_see_skb(skb, rxrpc_skb_see_unshare_nomem);
+			ret = -ENOMEM;
+		}
+	} else {
+		ret = conn->security->verify_response(conn, skb);
+	}
+
+	return ret;
+}
+
 /*
  * connection-level Rx packet processor
  */
@@ -253,7 +280,7 @@ static int rxrpc_process_event(struct rxrpc_connection *conn,
 		}
 		spin_unlock(&conn->state_lock);
 
-		ret = conn->security->verify_response(conn, skb);
+		ret = rxrpc_verify_response(conn, skb);
 		if (ret < 0)
 			return ret;
 
-- 
2.30.2

[PATCH 2/2] rxrpc: Also unshare DATA/RESPONSE packets when paged frags are present

[Wentao Guan]

From: Hyunwoo Kim <imv4bel@gmail.com>

The DATA-packet handler in rxrpc_input_call_event() and the RESPONSE
handler in rxrpc_verify_response() copy the skb to a linear one before
calling into the security ops only when skb_cloned() is true.  An skb
that is not cloned but still carries externally-owned paged fragments
(e.g. SKBFL_SHARED_FRAG set by splice() into a UDP socket via
__ip_append_data, or a chained skb_has_frag_list()) falls through to
the in-place decryption path, which binds the frag pages directly into
the AEAD/skcipher SGL via skb_to_sgvec().

Extend the gate to also unshare when skb_has_frag_list() or
skb_has_shared_frag() is true.  This catches the splice-loopback vector
and other externally-shared frag sources while preserving the
zero-copy fast path for skbs whose frags are kernel-private (e.g. NIC
page_pool RX, GRO).  The OOM/trace handling already in place is reused.

Fixes: d0d5c0cd1e71 ("rxrpc: Use skb_unshare() rather than skb_cow_data()")
Cc: stable@vger.kernel.org
Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com>
Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit aa54b1d27fe0c2b78e664a34fd0fdf7cd1960d71)
Signed-off-by: Wentao Guan <guanwentao@uniontech.com>
---
 net/rxrpc/call_event.c | 4 +++-
 net/rxrpc/conn_event.c | 3 ++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/net/rxrpc/call_event.c b/net/rxrpc/call_event.c
index 62ddaa129ce5a..fda16b39e8e73 100644
--- a/net/rxrpc/call_event.c
+++ b/net/rxrpc/call_event.c
@@ -347,7 +347,9 @@ bool rxrpc_input_call_event(struct rxrpc_call *call, struct sk_buff *skb)
 
 		if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA &&
 		    sp->hdr.securityIndex != 0 &&
-		    skb_cloned(skb)) {
+		    (skb_cloned(skb) ||
+		     skb_has_frag_list(skb) ||
+		     skb_has_shared_frag(skb))) {
 			/* Unshare the packet so that it can be modified for
 			 * in-place decryption.
 			 */
diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c
index 6dcfaed1f7485..3a58fb9210383 100644
--- a/net/rxrpc/conn_event.c
+++ b/net/rxrpc/conn_event.c
@@ -231,7 +231,8 @@ static int rxrpc_verify_response(struct rxrpc_connection *conn,
 {
 	int ret;
 
-	if (skb_cloned(skb)) {
+	if (skb_cloned(skb) || skb_has_frag_list(skb) ||
+	    skb_has_shared_frag(skb)) {
 		/* Copy the packet if shared so that we can do in-place
 		 * decryption.
 		 */
-- 
2.30.2

[PATCH 6.12 v2 1/2] rxrpc: Fix conn-level packet handling to unshare RESPONSE packets

[Wentao Guan]

From: David Howells <dhowells@redhat.com>

The security operations that verify the RESPONSE packets decrypt bits of it
in place - however, the sk_buff may be shared with a packet sniffer, which
would lead to the sniffer seeing an apparently corrupt packet (actually
decrypted).

Fix this by handing a copy of the packet off to the specific security
handler if the packet was cloned.

Fixes: 17926a79320a ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both")
Closes: https://sashiko.dev/#/patchset/20260408121252.2249051-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Jeffrey Altman <jaltman@auristor.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
Link: https://patch.msgid.link/20260422161438.2593376-5-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
(cherry picked from commit 24481a7f573305706054c59e275371f8d0fe919f)
[Readd rxrpc_skb_put_response_copy which missed in 016725807ce3 in v6.12.86]
Stable-dep-of: aa54b1d27fe0 ("rxrpc: Also unshare DATA/RESPONSE packets when
paged frags are present")
Signed-off-by: Wentao Guan <guanwentao@uniontech.com>
---
 include/trace/events/rxrpc.h |  1 +
 net/rxrpc/conn_event.c       | 29 ++++++++++++++++++++++++++++-
 2 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/include/trace/events/rxrpc.h b/include/trace/events/rxrpc.h
index 9377acad0c5f9..e42ead95362ae 100644
--- a/include/trace/events/rxrpc.h
+++ b/include/trace/events/rxrpc.h
@@ -146,6 +146,7 @@
 	EM(rxrpc_skb_put_jumbo_subpacket,	"PUT jumbo-sub") \
 	EM(rxrpc_skb_put_last_nack,		"PUT last-nack") \
 	EM(rxrpc_skb_put_purge,			"PUT purge    ") \
+	EM(rxrpc_skb_put_response,		"PUT resp-cpy ") \
 	EM(rxrpc_skb_put_rotate,		"PUT rotate   ") \
 	EM(rxrpc_skb_put_unknown,		"PUT unknown  ") \
 	EM(rxrpc_skb_see_conn_work,		"SEE conn-work") \
diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c
index 82cc72123c9c9..6dcfaed1f7485 100644
--- a/net/rxrpc/conn_event.c
+++ b/net/rxrpc/conn_event.c
@@ -226,6 +226,33 @@ static void rxrpc_call_is_secure(struct rxrpc_call *call)
 		rxrpc_notify_socket(call);
 }
 
+static int rxrpc_verify_response(struct rxrpc_connection *conn,
+				 struct sk_buff *skb)
+{
+	int ret;
+
+	if (skb_cloned(skb)) {
+		/* Copy the packet if shared so that we can do in-place
+		 * decryption.
+		 */
+		struct sk_buff *nskb = skb_copy(skb, GFP_NOFS);
+
+		if (nskb) {
+			rxrpc_new_skb(nskb, rxrpc_skb_new_unshared);
+			ret = conn->security->verify_response(conn, nskb);
+			rxrpc_free_skb(nskb, rxrpc_skb_put_response_copy);
+		} else {
+			/* OOM - Drop the packet. */
+			rxrpc_see_skb(skb, rxrpc_skb_see_unshare_nomem);
+			ret = -ENOMEM;
+		}
+	} else {
+		ret = conn->security->verify_response(conn, skb);
+	}
+
+	return ret;
+}
+
 /*
  * connection-level Rx packet processor
  */
@@ -253,7 +280,7 @@ static int rxrpc_process_event(struct rxrpc_connection *conn,
 		}
 		spin_unlock(&conn->state_lock);
 
-		ret = conn->security->verify_response(conn, skb);
+		ret = rxrpc_verify_response(conn, skb);
 		if (ret < 0)
 			return ret;
 
-- 
2.30.2

[PATCH 6.12 v2 2/2] rxrpc: Also unshare DATA/RESPONSE packets when paged frags are present

[Wentao Guan]

From: Hyunwoo Kim <imv4bel@gmail.com>

The DATA-packet handler in rxrpc_input_call_event() and the RESPONSE
handler in rxrpc_verify_response() copy the skb to a linear one before
calling into the security ops only when skb_cloned() is true.  An skb
that is not cloned but still carries externally-owned paged fragments
(e.g. SKBFL_SHARED_FRAG set by splice() into a UDP socket via
__ip_append_data, or a chained skb_has_frag_list()) falls through to
the in-place decryption path, which binds the frag pages directly into
the AEAD/skcipher SGL via skb_to_sgvec().

Extend the gate to also unshare when skb_has_frag_list() or
skb_has_shared_frag() is true.  This catches the splice-loopback vector
and other externally-shared frag sources while preserving the
zero-copy fast path for skbs whose frags are kernel-private (e.g. NIC
page_pool RX, GRO).  The OOM/trace handling already in place is reused.

Fixes: d0d5c0cd1e71 ("rxrpc: Use skb_unshare() rather than skb_cow_data()")
Cc: stable@vger.kernel.org
Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com>
Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit aa54b1d27fe0c2b78e664a34fd0fdf7cd1960d71)
Signed-off-by: Wentao Guan <guanwentao@uniontech.com>
---
 net/rxrpc/call_event.c | 4 +++-
 net/rxrpc/conn_event.c | 3 ++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/net/rxrpc/call_event.c b/net/rxrpc/call_event.c
index 62ddaa129ce5a..fda16b39e8e73 100644
--- a/net/rxrpc/call_event.c
+++ b/net/rxrpc/call_event.c
@@ -347,7 +347,9 @@ bool rxrpc_input_call_event(struct rxrpc_call *call, struct sk_buff *skb)
 
 		if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA &&
 		    sp->hdr.securityIndex != 0 &&
-		    skb_cloned(skb)) {
+		    (skb_cloned(skb) ||
+		     skb_has_frag_list(skb) ||
+		     skb_has_shared_frag(skb))) {
 			/* Unshare the packet so that it can be modified for
 			 * in-place decryption.
 			 */
diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c
index 6dcfaed1f7485..3a58fb9210383 100644
--- a/net/rxrpc/conn_event.c
+++ b/net/rxrpc/conn_event.c
@@ -231,7 +231,8 @@ static int rxrpc_verify_response(struct rxrpc_connection *conn,
 {
 	int ret;
 
-	if (skb_cloned(skb)) {
+	if (skb_cloned(skb) || skb_has_frag_list(skb) ||
+	    skb_has_shared_frag(skb)) {
 		/* Copy the packet if shared so that we can do in-place
 		 * decryption.
 		 */
-- 
2.30.2

Re: [PATCH 2/2] rxrpc: Also unshare DATA/RESPONSE packets when paged frags are present

[Greg KH]

On Mon, May 11, 2026 at 03:18:33PM +0800, Wentao Guan wrote:
> From: Hyunwoo Kim <imv4bel@gmail.com>
> 
> The DATA-packet handler in rxrpc_input_call_event() and the RESPONSE
> handler in rxrpc_verify_response() copy the skb to a linear one before
> calling into the security ops only when skb_cloned() is true.  An skb
> that is not cloned but still carries externally-owned paged fragments
> (e.g. SKBFL_SHARED_FRAG set by splice() into a UDP socket via
> __ip_append_data, or a chained skb_has_frag_list()) falls through to
> the in-place decryption path, which binds the frag pages directly into
> the AEAD/skcipher SGL via skb_to_sgvec().
> 
> Extend the gate to also unshare when skb_has_frag_list() or
> skb_has_shared_frag() is true.  This catches the splice-loopback vector
> and other externally-shared frag sources while preserving the
> zero-copy fast path for skbs whose frags are kernel-private (e.g. NIC
> page_pool RX, GRO).  The OOM/trace handling already in place is reused.
> 
> Fixes: d0d5c0cd1e71 ("rxrpc: Use skb_unshare() rather than skb_cow_data()")
> Cc: stable@vger.kernel.org
> Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com>
> Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev>
> Acked-by: David Howells <dhowells@redhat.com>
> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
> (cherry picked from commit aa54b1d27fe0c2b78e664a34fd0fdf7cd1960d71)
> Signed-off-by: Wentao Guan <guanwentao@uniontech.com>
> ---
>  net/rxrpc/call_event.c | 4 +++-
>  net/rxrpc/conn_event.c | 3 ++-
>  2 files changed, 5 insertions(+), 2 deletions(-)

Same here, what branches is this for?

thanks,

greg k-h

Re: Re: [PATCH 1/2] rxrpc: Fix conn-level packet handling to unshare RESPONSE packets

[Wentao Guan]

Sorry, it is for 6.12.
But miss fixes in https://lore.kernel.org/stable/20260508083142.1752208-1-guanwentao@uniontech.com/,
will cause build failed with no rxrpc_skb_put_response_copy,
which introduced in 1f2740150f904bfa60e4bad74d65add3ccb5e7f8.

BRs
Wentao Guan

Re: Re: [PATCH 1/2] rxrpc: Fix conn-level packet handling to unshare RESPONSE packets

[Greg KH]

On Mon, May 11, 2026 at 03:33:51PM +0800, Wentao Guan wrote:
> Sorry, it is for 6.12.

What is?

> But miss fixes in https://lore.kernel.org/stable/20260508083142.1752208-1-guanwentao@uniontech.com/,
> will cause build failed with no rxrpc_skb_put_response_copy,
> which introduced in 1f2740150f904bfa60e4bad74d65add3ccb5e7f8.

I am sorry, but I do not understand what you are asking for here.

confused,

greg k-h

[PATCH 6.12.y v3 1/2] rxrpc: Fix conn-level packet handling to unshare RESPONSE packets

[Wentao Guan]

From: David Howells <dhowells@redhat.com>

The security operations that verify the RESPONSE packets decrypt bits of it
in place - however, the sk_buff may be shared with a packet sniffer, which
would lead to the sniffer seeing an apparently corrupt packet (actually
decrypted).

Fix this by handing a copy of the packet off to the specific security
handler if the packet was cloned.

Fixes: 17926a79320a ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both")
Closes: https://sashiko.dev/#/patchset/20260408121252.2249051-1-dhowells%40redhat.com
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Jeffrey Altman <jaltman@auristor.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
Link: https://patch.msgid.link/20260422161438.2593376-5-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
(cherry picked from commit 24481a7f573305706054c59e275371f8d0fe919f)
[Readd rxrpc_skb_put_response_copy which missed in 016725807ce3 in v6.12.86]
Stable-dep-of: aa54b1d27fe0 ("rxrpc: Also unshare DATA/RESPONSE packets when
paged frags are present")
Signed-off-by: Wentao Guan <guanwentao@uniontech.com>
---
 include/trace/events/rxrpc.h |  1 +
 net/rxrpc/conn_event.c       | 29 ++++++++++++++++++++++++++++-
 2 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/include/trace/events/rxrpc.h b/include/trace/events/rxrpc.h
index 9377acad0c5f9..63efc9e4e4102 100644
--- a/include/trace/events/rxrpc.h
+++ b/include/trace/events/rxrpc.h
@@ -146,6 +146,7 @@
 	EM(rxrpc_skb_put_jumbo_subpacket,	"PUT jumbo-sub") \
 	EM(rxrpc_skb_put_last_nack,		"PUT last-nack") \
 	EM(rxrpc_skb_put_purge,			"PUT purge    ") \
+	EM(rxrpc_skb_put_response_copy,		"PUT resp-cpy ") \
 	EM(rxrpc_skb_put_rotate,		"PUT rotate   ") \
 	EM(rxrpc_skb_put_unknown,		"PUT unknown  ") \
 	EM(rxrpc_skb_see_conn_work,		"SEE conn-work") \
diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c
index 82cc72123c9c9..6dcfaed1f7485 100644
--- a/net/rxrpc/conn_event.c
+++ b/net/rxrpc/conn_event.c
@@ -226,6 +226,33 @@ static void rxrpc_call_is_secure(struct rxrpc_call *call)
 		rxrpc_notify_socket(call);
 }
 
+static int rxrpc_verify_response(struct rxrpc_connection *conn,
+				 struct sk_buff *skb)
+{
+	int ret;
+
+	if (skb_cloned(skb)) {
+		/* Copy the packet if shared so that we can do in-place
+		 * decryption.
+		 */
+		struct sk_buff *nskb = skb_copy(skb, GFP_NOFS);
+
+		if (nskb) {
+			rxrpc_new_skb(nskb, rxrpc_skb_new_unshared);
+			ret = conn->security->verify_response(conn, nskb);
+			rxrpc_free_skb(nskb, rxrpc_skb_put_response_copy);
+		} else {
+			/* OOM - Drop the packet. */
+			rxrpc_see_skb(skb, rxrpc_skb_see_unshare_nomem);
+			ret = -ENOMEM;
+		}
+	} else {
+		ret = conn->security->verify_response(conn, skb);
+	}
+
+	return ret;
+}
+
 /*
  * connection-level Rx packet processor
  */
@@ -253,7 +280,7 @@ static int rxrpc_process_event(struct rxrpc_connection *conn,
 		}
 		spin_unlock(&conn->state_lock);
 
-		ret = conn->security->verify_response(conn, skb);
+		ret = rxrpc_verify_response(conn, skb);
 		if (ret < 0)
 			return ret;
 
-- 
2.30.2

Re: [PATCH 6.12.y v3 1/2] rxrpc: Fix conn-level packet handling to unshare RESPONSE packets

[Harshit Mogalapalli]

Hi,


On 11/05/26 13:11, Wentao Guan wrote:
> [Readd rxrpc_skb_put_response_copy which missed in 016725807ce3 in v6.12.86]
> Stable-dep-of: aa54b1d27fe0 ("rxrpc: Also unshare DATA/RESPONSE packets when
> paged frags are present")

Yes, I noticed this too.

But you got the commit wrong I think: (you probably meant)

the rxrpc_skb_put_response_copy() addition was missed in commit: 
bf20f46d94f1 ("rxrpc: Fix potential UAF after skb_unshare() failure")

Greg: Summary: (it might help)

The stable backport bf20f46d94f1 ("rxrpc: Fix potential UAF after 
skb_unshare() failure") is a backport of commit: 1f2740150f90 ("rxrpc: 
Fix potential UAF after skb_unshare() failure") to 6.12.y:


stable backport bf20f46d94f1 ("rxrpc: Fix potential UAF after 
skb_unshare() failure") adds this which is not part of upstream commit:
+       EM(rxrpc_skb_get_call_rx,               "GET call-rx  ") \

But missed adding: which is added in upstream commit:
+       EM(rxrpc_skb_put_response_copy,         "PUT resp-cpy ") \


Hence Wentao needs to add rxrpc_skb_put_response_copy() in this backport.


Thanks,
Harshit



> Signed-off-by: Wentao Guan<guanwentao@uniontech.com>
> ---
>   include/trace/events/rxrpc.h |  1 +
>   net/rxrpc/conn_event.c       | 29 ++++++++++++++++++++++++++++-
>   2 files changed, 29 insertions(+), 1 deletion(-)
> 
> diff --git a/include/trace/events/rxrpc.h b/include/trace/events/rxrpc.h
> index 9377acad0c5f9..63efc9e4e4102 100644
> --- a/include/trace/events/rxrpc.h
> +++ b/include/trace/events/rxrpc.h
> @@ -146,6 +146,7 @@
>   	EM(rxrpc_skb_put_jumbo_subpacket,	"PUT jumbo-sub") \
>   	EM(rxrpc_skb_put_last_nack,		"PUT last-nack") \
>   	EM(rxrpc_skb_put_purge,			"PUT purge    ") \
> +	EM(rxrpc_skb_put_response_copy,		"PUT resp-cpy ") \




>   	EM(rxrpc_skb_put_rotate,		"PUT rotate   ") \
>   	EM(rxrpc_skb_put_unknown,		"PUT unknown  ") \
>   	EM(rxrpc_skb_see_conn_work,		"SEE conn-work") \
> diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c
> index 82cc72123c9c9..6dcfaed1f7485 100644
> --- a/net/rxrpc/conn_event.c
> +++ b/net/rxrpc/conn_event.c
> @@ -226,6 +226,33 @@ static void rxrpc_call_is_secure(struct rxrpc_call *call)
>   		rxrpc_notify_socket(call);
>   }

Re: Re: [PATCH 6.12.y v3 1/2] rxrpc: Fix conn-level packet handling to unshare RESPONSE packets

[Wentao Guan]

> On 11/05/26 13:11, Wentao Guan wrote:
> > [Readd rxrpc_skb_put_response_copy which missed in 016725807ce3 in v6.12.86]
> > Stable-dep-of: aa54b1d27fe0 ("rxrpc: Also unshare DATA/RESPONSE packets when
> > paged frags are present")

> Yes, I noticed this too.
Well

> But you got the commit wrong I think: (you probably meant)
Thanks, i paste wrong commit here, which i reported in
https://lore.kernel.org/stable/20260508083142.1752208-1-guanwentao@uniontech.com/
SUMMARY:
commit ("rxrpc: Fix potential UAF after skb_unshare() failure"):
bf20f46d94f1db38e6ffc0ca204a5fe0de01b495 v6.12
1f2740150f904bfa60e4bad74d65add3ccb5e7f8 upstream
is different

> Hence Wentao needs to add rxrpc_skb_put_response_copy() in this backport.
Yeah.

BRs
Wentao Guan

Re: [PATCH 6.12.y v3 1/2] rxrpc: Fix conn-level packet handling to unshare RESPONSE packets

[Sasha Levin]

On Mon, May 11, 2026 at 03:41:04PM +0800, Wentao Guan wrote:
> (cherry picked from commit 24481a7f573305706054c59e275371f8d0fe919f)
> [Readd rxrpc_skb_put_response_copy which missed in 016725807ce3 in v6.12.86]
> Stable-dep-of: aa54b1d27fe0 ("rxrpc: Also unshare DATA/RESPONSE packets when
> paged frags are present")

Queued for 6.12 (both 1/2 and 2/2), thanks.

I fixed up the bracket annotation at apply time per Harshit's review:
the trace event was actually dropped in bf20f46d94f1 ("rxrpc: Fix
potential UAF after skb_unshare() failure"), not 016725807ce3, so the
queued changelog references bf20f46d94f1.

-- 
Thanks,
Sasha

Re: Re: [PATCH 6.12.y v3 1/2] rxrpc: Fix conn-level packet handling to unshare RESPONSE packets

[Wentao Guan]

> Queued for 6.12 (both 1/2 and 2/2), thanks.

> I fixed up the bracket annotation at apply time per Harshit's review:
> the trace event was actually dropped in bf20f46d94f1 ("rxrpc: Fix
> potential UAF after skb_unshare() failure"), not 016725807ce3, so the
> queued changelog references bf20f46d94f1.

Thanks.

BRs
Wentao Guan

[PATCH 6.12.y v3 2/2] rxrpc: Also unshare DATA/RESPONSE packets when paged frags are present

[Wentao Guan]

From: Hyunwoo Kim <imv4bel@gmail.com>

The DATA-packet handler in rxrpc_input_call_event() and the RESPONSE
handler in rxrpc_verify_response() copy the skb to a linear one before
calling into the security ops only when skb_cloned() is true.  An skb
that is not cloned but still carries externally-owned paged fragments
(e.g. SKBFL_SHARED_FRAG set by splice() into a UDP socket via
__ip_append_data, or a chained skb_has_frag_list()) falls through to
the in-place decryption path, which binds the frag pages directly into
the AEAD/skcipher SGL via skb_to_sgvec().

Extend the gate to also unshare when skb_has_frag_list() or
skb_has_shared_frag() is true.  This catches the splice-loopback vector
and other externally-shared frag sources while preserving the
zero-copy fast path for skbs whose frags are kernel-private (e.g. NIC
page_pool RX, GRO).  The OOM/trace handling already in place is reused.

Fixes: d0d5c0cd1e71 ("rxrpc: Use skb_unshare() rather than skb_cow_data()")
Cc: stable@vger.kernel.org
Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com>
Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit aa54b1d27fe0c2b78e664a34fd0fdf7cd1960d71)
Signed-off-by: Wentao Guan <guanwentao@uniontech.com>
---
 net/rxrpc/call_event.c | 4 +++-
 net/rxrpc/conn_event.c | 3 ++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/net/rxrpc/call_event.c b/net/rxrpc/call_event.c
index 62ddaa129ce5a..fda16b39e8e73 100644
--- a/net/rxrpc/call_event.c
+++ b/net/rxrpc/call_event.c
@@ -347,7 +347,9 @@ bool rxrpc_input_call_event(struct rxrpc_call *call, struct sk_buff *skb)
 
 		if (sp->hdr.type == RXRPC_PACKET_TYPE_DATA &&
 		    sp->hdr.securityIndex != 0 &&
-		    skb_cloned(skb)) {
+		    (skb_cloned(skb) ||
+		     skb_has_frag_list(skb) ||
+		     skb_has_shared_frag(skb))) {
 			/* Unshare the packet so that it can be modified for
 			 * in-place decryption.
 			 */
diff --git a/net/rxrpc/conn_event.c b/net/rxrpc/conn_event.c
index 6dcfaed1f7485..3a58fb9210383 100644
--- a/net/rxrpc/conn_event.c
+++ b/net/rxrpc/conn_event.c
@@ -231,7 +231,8 @@ static int rxrpc_verify_response(struct rxrpc_connection *conn,
 {
 	int ret;
 
-	if (skb_cloned(skb)) {
+	if (skb_cloned(skb) || skb_has_frag_list(skb) ||
+	    skb_has_shared_frag(skb)) {
 		/* Copy the packet if shared so that we can do in-place
 		 * decryption.
 		 */
-- 
2.30.2

Re: [PATCH 1/2] rxrpc: Fix conn-level packet handling to unshare RESPONSE packets

[Wentao Guan]

Sorry, FYI ,it is only for 6.12.y, PATCH v1 which i sent 
will cause build failed with no rxrpc_skb_put_response_copy,
and v2 also broken,
which introduced in 1f2740150f904bfa60e4bad74d65add3ccb5e7f8.

BRs
Wentao Guan

Re: [PATCH 1/2] rxrpc: Fix conn-level packet handling to unshare RESPONSE packets

[Greg KH]

On Mon, May 11, 2026 at 03:18:32PM +0800, Wentao Guan wrote:
> From: David Howells <dhowells@redhat.com>
> 
> The security operations that verify the RESPONSE packets decrypt bits of it
> in place - however, the sk_buff may be shared with a packet sniffer, which
> would lead to the sniffer seeing an apparently corrupt packet (actually
> decrypted).
> 
> Fix this by handing a copy of the packet off to the specific security
> handler if the packet was cloned.
> 
> Fixes: 17926a79320a ("[AF_RXRPC]: Provide secure RxRPC sockets for use by userspace and kernel both")
> Closes: https://sashiko.dev/#/patchset/20260408121252.2249051-1-dhowells%40redhat.com
> Signed-off-by: David Howells <dhowells@redhat.com>
> cc: Marc Dionne <marc.dionne@auristor.com>
> cc: Jeffrey Altman <jaltman@auristor.com>
> cc: Simon Horman <horms@kernel.org>
> cc: linux-afs@lists.infradead.org
> cc: stable@kernel.org
> Link: https://patch.msgid.link/20260422161438.2593376-5-dhowells@redhat.com
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
> (cherry picked from commit 24481a7f573305706054c59e275371f8d0fe919f)
> Stable-dep-of: aa54b1d27fe0 ("rxrpc: Also unshare DATA/RESPONSE packets when
> paged frags are present")
> Signed-off-by: Wentao Guan <guanwentao@uniontech.com>
> ---
>  net/rxrpc/conn_event.c | 29 ++++++++++++++++++++++++++++-
>  1 file changed, 28 insertions(+), 1 deletion(-)

What branch(es) are you wanting this applied to?

thanks,

greg k-h