FAILED: patch "[PATCH] rxrpc: proc: size address buffers for %pISpc output" failed to apply to 6.12-stable tree

FAILED: patch "[PATCH] rxrpc: proc: size address buffers for %pISpc output" 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 a44ce6aa2efb61fe44f2cfab72bb01544bbca272
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026041326-engaged-snowbird-df74@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

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

From a44ce6aa2efb61fe44f2cfab72bb01544bbca272 Mon Sep 17 00:00:00 2001
From: Pengpeng Hou <pengpeng@iscas.ac.cn>
Date: Wed, 8 Apr 2026 13:12:49 +0100
Subject: [PATCH] rxrpc: proc: size address buffers for %pISpc output

The AF_RXRPC procfs helpers format local and remote socket addresses into
fixed 50-byte stack buffers with "%pISpc".

That is too small for the longest current-tree IPv6-with-port form the
formatter can produce. In lib/vsprintf.c, the compressed IPv6 path uses a
dotted-quad tail not only for v4mapped addresses, but also for ISATAP
addresses via ipv6_addr_is_isatap().

As a result, a case such as

  [ffff:ffff:ffff:ffff:0:5efe:255.255.255.255]:65535

is possible with the current formatter. That is 50 visible characters, so
51 bytes including the trailing NUL, which does not fit in the existing
char[50] buffers used by net/rxrpc/proc.c.

Size the buffers from the formatter's maximum textual form and switch the
call sites to scnprintf().

Changes since v1:
- correct the changelog to cite the actual maximum current-tree case
  explicitly
- frame the proof around the ISATAP formatting path instead of the earlier
  mapped-v4 example

Fixes: 75b54cb57ca3 ("rxrpc: Add IPv6 support")
Signed-off-by: Pengpeng Hou <pengpeng@iscas.ac.cn>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Anderson Nascimento <anderson@allelesecurity.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
Link: https://patch.msgid.link/20260408121252.2249051-22-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/rxrpc/proc.c b/net/rxrpc/proc.c
index 7755fca5beb8..e9a27fa7b25d 100644
--- a/net/rxrpc/proc.c
+++ b/net/rxrpc/proc.c
@@ -10,6 +10,10 @@
 #include <net/af_rxrpc.h>
 #include "ar-internal.h"
 
+#define RXRPC_PROC_ADDRBUF_SIZE \
+	(sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") + \
+	 sizeof(":12345"))
+
 static const char *const rxrpc_conn_states[RXRPC_CONN__NR_STATES] = {
 	[RXRPC_CONN_UNUSED]			= "Unused  ",
 	[RXRPC_CONN_CLIENT_UNSECURED]		= "ClUnsec ",
@@ -53,7 +57,7 @@ static int rxrpc_call_seq_show(struct seq_file *seq, void *v)
 	struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
 	enum rxrpc_call_state state;
 	rxrpc_seq_t tx_bottom;
-	char lbuff[50], rbuff[50];
+	char lbuff[RXRPC_PROC_ADDRBUF_SIZE], rbuff[RXRPC_PROC_ADDRBUF_SIZE];
 	long timeout = 0;
 
 	if (v == &rxnet->calls) {
@@ -69,11 +73,11 @@ static int rxrpc_call_seq_show(struct seq_file *seq, void *v)
 
 	local = call->local;
 	if (local)
-		sprintf(lbuff, "%pISpc", &local->srx.transport);
+		scnprintf(lbuff, sizeof(lbuff), "%pISpc", &local->srx.transport);
 	else
 		strcpy(lbuff, "no_local");
 
-	sprintf(rbuff, "%pISpc", &call->dest_srx.transport);
+	scnprintf(rbuff, sizeof(rbuff), "%pISpc", &call->dest_srx.transport);
 
 	state = rxrpc_call_state(call);
 	if (state != RXRPC_CALL_SERVER_PREALLOC)
@@ -142,7 +146,7 @@ static int rxrpc_connection_seq_show(struct seq_file *seq, void *v)
 	struct rxrpc_connection *conn;
 	struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
 	const char *state;
-	char lbuff[50], rbuff[50];
+	char lbuff[RXRPC_PROC_ADDRBUF_SIZE], rbuff[RXRPC_PROC_ADDRBUF_SIZE];
 
 	if (v == &rxnet->conn_proc_list) {
 		seq_puts(seq,
@@ -161,8 +165,8 @@ static int rxrpc_connection_seq_show(struct seq_file *seq, void *v)
 		goto print;
 	}
 
-	sprintf(lbuff, "%pISpc", &conn->local->srx.transport);
-	sprintf(rbuff, "%pISpc", &conn->peer->srx.transport);
+	scnprintf(lbuff, sizeof(lbuff), "%pISpc", &conn->local->srx.transport);
+	scnprintf(rbuff, sizeof(rbuff), "%pISpc", &conn->peer->srx.transport);
 print:
 	state = rxrpc_is_conn_aborted(conn) ?
 		rxrpc_call_completions[conn->completion] :
@@ -228,7 +232,7 @@ static int rxrpc_bundle_seq_show(struct seq_file *seq, void *v)
 {
 	struct rxrpc_bundle *bundle;
 	struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
-	char lbuff[50], rbuff[50];
+	char lbuff[RXRPC_PROC_ADDRBUF_SIZE], rbuff[RXRPC_PROC_ADDRBUF_SIZE];
 
 	if (v == &rxnet->bundle_proc_list) {
 		seq_puts(seq,
@@ -242,8 +246,8 @@ static int rxrpc_bundle_seq_show(struct seq_file *seq, void *v)
 
 	bundle = list_entry(v, struct rxrpc_bundle, proc_link);
 
-	sprintf(lbuff, "%pISpc", &bundle->local->srx.transport);
-	sprintf(rbuff, "%pISpc", &bundle->peer->srx.transport);
+	scnprintf(lbuff, sizeof(lbuff), "%pISpc", &bundle->local->srx.transport);
+	scnprintf(rbuff, sizeof(rbuff), "%pISpc", &bundle->peer->srx.transport);
 	seq_printf(seq,
 		   "UDP   %-47.47s %-47.47s %4x %3u %3d"
 		   " %c%c%c %08x | %08x %08x %08x %08x %08x\n",
@@ -279,7 +283,7 @@ static int rxrpc_peer_seq_show(struct seq_file *seq, void *v)
 {
 	struct rxrpc_peer *peer;
 	time64_t now;
-	char lbuff[50], rbuff[50];
+	char lbuff[RXRPC_PROC_ADDRBUF_SIZE], rbuff[RXRPC_PROC_ADDRBUF_SIZE];
 
 	if (v == SEQ_START_TOKEN) {
 		seq_puts(seq,
@@ -290,9 +294,9 @@ static int rxrpc_peer_seq_show(struct seq_file *seq, void *v)
 
 	peer = list_entry(v, struct rxrpc_peer, hash_link);
 
-	sprintf(lbuff, "%pISpc", &peer->local->srx.transport);
+	scnprintf(lbuff, sizeof(lbuff), "%pISpc", &peer->local->srx.transport);
 
-	sprintf(rbuff, "%pISpc", &peer->srx.transport);
+	scnprintf(rbuff, sizeof(rbuff), "%pISpc", &peer->srx.transport);
 
 	now = ktime_get_seconds();
 	seq_printf(seq,
@@ -401,7 +405,7 @@ const struct seq_operations rxrpc_peer_seq_ops = {
 static int rxrpc_local_seq_show(struct seq_file *seq, void *v)
 {
 	struct rxrpc_local *local;
-	char lbuff[50];
+	char lbuff[RXRPC_PROC_ADDRBUF_SIZE];
 
 	if (v == SEQ_START_TOKEN) {
 		seq_puts(seq,
@@ -412,7 +416,7 @@ static int rxrpc_local_seq_show(struct seq_file *seq, void *v)
 
 	local = hlist_entry(v, struct rxrpc_local, link);
 
-	sprintf(lbuff, "%pISpc", &local->srx.transport);
+	scnprintf(lbuff, sizeof(lbuff), "%pISpc", &local->srx.transport);
 
 	seq_printf(seq,
 		   "UDP   %-47.47s %3u %3u %3u\n",

[PATCH 6.12.y 1/2] rxrpc: Don't need barrier for ->tx_bottom and ->acks_hard_ack

[Sasha Levin]

From: David Howells <dhowells@redhat.com>

[ Upstream commit 6396b48ac0a77165f9c2c40ab03d6c8188c89739 ]

We don't need a barrier for the ->tx_bottom value (which indicates the
lowest sequence still in the transmission queue) and the ->acks_hard_ack
value (which tracks the DATA packets hard-ack'd by the latest ACK packet
received and thus indicates which DATA packets can now be discarded) as the
app thread doesn't use either value as a reference to memory to access.
Rather, the app thread merely uses these as a guide to how much space is
available in the transmission queue

Change the code to use READ/WRITE_ONCE() instead.

Also, change rxrpc_check_tx_space() to use the same value for tx_bottom
throughout.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Link: https://patch.msgid.link/20241204074710.990092-18-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: c43ffdcfdbb5 ("rxrpc: only handle RESPONSE during service challenge")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/rxrpc/sendmsg.c | 8 +++++---
 net/rxrpc/txbuf.c   | 4 ++--
 2 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c
index 154f650efb0ab..2f2c2fe739ffc 100644
--- a/net/rxrpc/sendmsg.c
+++ b/net/rxrpc/sendmsg.c
@@ -93,9 +93,11 @@ static int rxrpc_wait_to_be_connected(struct rxrpc_call *call, long *timeo)
  */
 static bool rxrpc_check_tx_space(struct rxrpc_call *call, rxrpc_seq_t *_tx_win)
 {
+	rxrpc_seq_t tx_bottom = READ_ONCE(call->tx_bottom);
+
 	if (_tx_win)
-		*_tx_win = call->tx_bottom;
-	return call->tx_prepared - call->tx_bottom < 256;
+		*_tx_win = tx_bottom;
+	return call->tx_prepared - tx_bottom < 256;
 }
 
 /*
@@ -137,7 +139,7 @@ static int rxrpc_wait_for_tx_window_waitall(struct rxrpc_sock *rx,
 		rtt = 2;
 
 	timeout = rtt;
-	tx_start = smp_load_acquire(&call->acks_hard_ack);
+	tx_start = READ_ONCE(call->acks_hard_ack);
 
 	for (;;) {
 		set_current_state(TASK_UNINTERRUPTIBLE);
diff --git a/net/rxrpc/txbuf.c b/net/rxrpc/txbuf.c
index c3913d8a50d34..a63e10fcd11c4 100644
--- a/net/rxrpc/txbuf.c
+++ b/net/rxrpc/txbuf.c
@@ -216,14 +216,14 @@ void rxrpc_shrink_call_tx_buffer(struct rxrpc_call *call)
 
 	while ((txb = list_first_entry_or_null(&call->tx_buffer,
 					       struct rxrpc_txbuf, call_link))) {
-		hard_ack = smp_load_acquire(&call->acks_hard_ack);
+		hard_ack = call->acks_hard_ack;
 		if (before(hard_ack, txb->seq))
 			break;
 
 		if (txb->seq != call->tx_bottom + 1)
 			rxrpc_see_txbuf(txb, rxrpc_txbuf_see_out_of_step);
 		ASSERTCMP(txb->seq, ==, call->tx_bottom + 1);
-		smp_store_release(&call->tx_bottom, call->tx_bottom + 1);
+		WRITE_ONCE(call->tx_bottom, call->tx_bottom + 1);
 		list_del_rcu(&txb->call_link);
 
 		trace_rxrpc_txqueue(call, rxrpc_txqueue_dequeue);
-- 
2.53.0

[PATCH 6.12.y 1/2] rxrpc: Don't need barrier for ->tx_bottom and ->acks_hard_ack

[Sasha Levin]

From: David Howells <dhowells@redhat.com>

[ Upstream commit 6396b48ac0a77165f9c2c40ab03d6c8188c89739 ]

We don't need a barrier for the ->tx_bottom value (which indicates the
lowest sequence still in the transmission queue) and the ->acks_hard_ack
value (which tracks the DATA packets hard-ack'd by the latest ACK packet
received and thus indicates which DATA packets can now be discarded) as the
app thread doesn't use either value as a reference to memory to access.
Rather, the app thread merely uses these as a guide to how much space is
available in the transmission queue

Change the code to use READ/WRITE_ONCE() instead.

Also, change rxrpc_check_tx_space() to use the same value for tx_bottom
throughout.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Link: https://patch.msgid.link/20241204074710.990092-18-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: a44ce6aa2efb ("rxrpc: proc: size address buffers for %pISpc output")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/rxrpc/sendmsg.c | 8 +++++---
 net/rxrpc/txbuf.c   | 4 ++--
 2 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c
index 154f650efb0ab..2f2c2fe739ffc 100644
--- a/net/rxrpc/sendmsg.c
+++ b/net/rxrpc/sendmsg.c
@@ -93,9 +93,11 @@ static int rxrpc_wait_to_be_connected(struct rxrpc_call *call, long *timeo)
  */
 static bool rxrpc_check_tx_space(struct rxrpc_call *call, rxrpc_seq_t *_tx_win)
 {
+	rxrpc_seq_t tx_bottom = READ_ONCE(call->tx_bottom);
+
 	if (_tx_win)
-		*_tx_win = call->tx_bottom;
-	return call->tx_prepared - call->tx_bottom < 256;
+		*_tx_win = tx_bottom;
+	return call->tx_prepared - tx_bottom < 256;
 }
 
 /*
@@ -137,7 +139,7 @@ static int rxrpc_wait_for_tx_window_waitall(struct rxrpc_sock *rx,
 		rtt = 2;
 
 	timeout = rtt;
-	tx_start = smp_load_acquire(&call->acks_hard_ack);
+	tx_start = READ_ONCE(call->acks_hard_ack);
 
 	for (;;) {
 		set_current_state(TASK_UNINTERRUPTIBLE);
diff --git a/net/rxrpc/txbuf.c b/net/rxrpc/txbuf.c
index c3913d8a50d34..a63e10fcd11c4 100644
--- a/net/rxrpc/txbuf.c
+++ b/net/rxrpc/txbuf.c
@@ -216,14 +216,14 @@ void rxrpc_shrink_call_tx_buffer(struct rxrpc_call *call)
 
 	while ((txb = list_first_entry_or_null(&call->tx_buffer,
 					       struct rxrpc_txbuf, call_link))) {
-		hard_ack = smp_load_acquire(&call->acks_hard_ack);
+		hard_ack = call->acks_hard_ack;
 		if (before(hard_ack, txb->seq))
 			break;
 
 		if (txb->seq != call->tx_bottom + 1)
 			rxrpc_see_txbuf(txb, rxrpc_txbuf_see_out_of_step);
 		ASSERTCMP(txb->seq, ==, call->tx_bottom + 1);
-		smp_store_release(&call->tx_bottom, call->tx_bottom + 1);
+		WRITE_ONCE(call->tx_bottom, call->tx_bottom + 1);
 		list_del_rcu(&txb->call_link);
 
 		trace_rxrpc_txqueue(call, rxrpc_txqueue_dequeue);
-- 
2.53.0

[PATCH 6.12.y 2/2] rxrpc: proc: size address buffers for %pISpc output

[Sasha Levin]

From: Pengpeng Hou <pengpeng@iscas.ac.cn>

[ Upstream commit a44ce6aa2efb61fe44f2cfab72bb01544bbca272 ]

The AF_RXRPC procfs helpers format local and remote socket addresses into
fixed 50-byte stack buffers with "%pISpc".

That is too small for the longest current-tree IPv6-with-port form the
formatter can produce. In lib/vsprintf.c, the compressed IPv6 path uses a
dotted-quad tail not only for v4mapped addresses, but also for ISATAP
addresses via ipv6_addr_is_isatap().

As a result, a case such as

  [ffff:ffff:ffff:ffff:0:5efe:255.255.255.255]:65535

is possible with the current formatter. That is 50 visible characters, so
51 bytes including the trailing NUL, which does not fit in the existing
char[50] buffers used by net/rxrpc/proc.c.

Size the buffers from the formatter's maximum textual form and switch the
call sites to scnprintf().

Changes since v1:
- correct the changelog to cite the actual maximum current-tree case
  explicitly
- frame the proof around the ISATAP formatting path instead of the earlier
  mapped-v4 example

Fixes: 75b54cb57ca3 ("rxrpc: Add IPv6 support")
Signed-off-by: Pengpeng Hou <pengpeng@iscas.ac.cn>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: Anderson Nascimento <anderson@allelesecurity.com>
cc: Simon Horman <horms@kernel.org>
cc: linux-afs@lists.infradead.org
cc: stable@kernel.org
Link: https://patch.msgid.link/20260408121252.2249051-22-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[ kept `acks_hard_ack` variable name instead of `tx_bottom` ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/rxrpc/proc.c | 32 ++++++++++++++++++--------------
 1 file changed, 18 insertions(+), 14 deletions(-)

diff --git a/net/rxrpc/proc.c b/net/rxrpc/proc.c
index ca85ac764f82b..aebe4e42634f9 100644
--- a/net/rxrpc/proc.c
+++ b/net/rxrpc/proc.c
@@ -10,6 +10,10 @@
 #include <net/af_rxrpc.h>
 #include "ar-internal.h"
 
+#define RXRPC_PROC_ADDRBUF_SIZE \
+	(sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") + \
+	 sizeof(":12345"))
+
 static const char *const rxrpc_conn_states[RXRPC_CONN__NR_STATES] = {
 	[RXRPC_CONN_UNUSED]			= "Unused  ",
 	[RXRPC_CONN_CLIENT_UNSECURED]		= "ClUnsec ",
@@ -53,7 +57,7 @@ static int rxrpc_call_seq_show(struct seq_file *seq, void *v)
 	struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
 	enum rxrpc_call_state state;
 	rxrpc_seq_t acks_hard_ack;
-	char lbuff[50], rbuff[50];
+	char lbuff[RXRPC_PROC_ADDRBUF_SIZE], rbuff[RXRPC_PROC_ADDRBUF_SIZE];
 	long timeout = 0;
 
 	if (v == &rxnet->calls) {
@@ -69,11 +73,11 @@ static int rxrpc_call_seq_show(struct seq_file *seq, void *v)
 
 	local = call->local;
 	if (local)
-		sprintf(lbuff, "%pISpc", &local->srx.transport);
+		scnprintf(lbuff, sizeof(lbuff), "%pISpc", &local->srx.transport);
 	else
 		strcpy(lbuff, "no_local");
 
-	sprintf(rbuff, "%pISpc", &call->dest_srx.transport);
+	scnprintf(rbuff, sizeof(rbuff), "%pISpc", &call->dest_srx.transport);
 
 	state = rxrpc_call_state(call);
 	if (state != RXRPC_CALL_SERVER_PREALLOC)
@@ -142,7 +146,7 @@ static int rxrpc_connection_seq_show(struct seq_file *seq, void *v)
 	struct rxrpc_connection *conn;
 	struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
 	const char *state;
-	char lbuff[50], rbuff[50];
+	char lbuff[RXRPC_PROC_ADDRBUF_SIZE], rbuff[RXRPC_PROC_ADDRBUF_SIZE];
 
 	if (v == &rxnet->conn_proc_list) {
 		seq_puts(seq,
@@ -161,8 +165,8 @@ static int rxrpc_connection_seq_show(struct seq_file *seq, void *v)
 		goto print;
 	}
 
-	sprintf(lbuff, "%pISpc", &conn->local->srx.transport);
-	sprintf(rbuff, "%pISpc", &conn->peer->srx.transport);
+	scnprintf(lbuff, sizeof(lbuff), "%pISpc", &conn->local->srx.transport);
+	scnprintf(rbuff, sizeof(rbuff), "%pISpc", &conn->peer->srx.transport);
 print:
 	state = rxrpc_is_conn_aborted(conn) ?
 		rxrpc_call_completions[conn->completion] :
@@ -228,7 +232,7 @@ static int rxrpc_bundle_seq_show(struct seq_file *seq, void *v)
 {
 	struct rxrpc_bundle *bundle;
 	struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
-	char lbuff[50], rbuff[50];
+	char lbuff[RXRPC_PROC_ADDRBUF_SIZE], rbuff[RXRPC_PROC_ADDRBUF_SIZE];
 
 	if (v == &rxnet->bundle_proc_list) {
 		seq_puts(seq,
@@ -242,8 +246,8 @@ static int rxrpc_bundle_seq_show(struct seq_file *seq, void *v)
 
 	bundle = list_entry(v, struct rxrpc_bundle, proc_link);
 
-	sprintf(lbuff, "%pISpc", &bundle->local->srx.transport);
-	sprintf(rbuff, "%pISpc", &bundle->peer->srx.transport);
+	scnprintf(lbuff, sizeof(lbuff), "%pISpc", &bundle->local->srx.transport);
+	scnprintf(rbuff, sizeof(rbuff), "%pISpc", &bundle->peer->srx.transport);
 	seq_printf(seq,
 		   "UDP   %-47.47s %-47.47s %4x %3u %3d"
 		   " %c%c%c %08x | %08x %08x %08x %08x %08x\n",
@@ -279,7 +283,7 @@ static int rxrpc_peer_seq_show(struct seq_file *seq, void *v)
 {
 	struct rxrpc_peer *peer;
 	time64_t now;
-	char lbuff[50], rbuff[50];
+	char lbuff[RXRPC_PROC_ADDRBUF_SIZE], rbuff[RXRPC_PROC_ADDRBUF_SIZE];
 
 	if (v == SEQ_START_TOKEN) {
 		seq_puts(seq,
@@ -292,9 +296,9 @@ static int rxrpc_peer_seq_show(struct seq_file *seq, void *v)
 
 	peer = list_entry(v, struct rxrpc_peer, hash_link);
 
-	sprintf(lbuff, "%pISpc", &peer->local->srx.transport);
+	scnprintf(lbuff, sizeof(lbuff), "%pISpc", &peer->local->srx.transport);
 
-	sprintf(rbuff, "%pISpc", &peer->srx.transport);
+	scnprintf(rbuff, sizeof(rbuff), "%pISpc", &peer->srx.transport);
 
 	now = ktime_get_seconds();
 	seq_printf(seq,
@@ -404,7 +408,7 @@ const struct seq_operations rxrpc_peer_seq_ops = {
 static int rxrpc_local_seq_show(struct seq_file *seq, void *v)
 {
 	struct rxrpc_local *local;
-	char lbuff[50];
+	char lbuff[RXRPC_PROC_ADDRBUF_SIZE];
 
 	if (v == SEQ_START_TOKEN) {
 		seq_puts(seq,
@@ -415,7 +419,7 @@ static int rxrpc_local_seq_show(struct seq_file *seq, void *v)
 
 	local = hlist_entry(v, struct rxrpc_local, link);
 
-	sprintf(lbuff, "%pISpc", &local->srx.transport);
+	scnprintf(lbuff, sizeof(lbuff), "%pISpc", &local->srx.transport);
 
 	seq_printf(seq,
 		   "UDP   %-47.47s %3u %3u %3u\n",
-- 
2.53.0