The patch below does not apply to the 5.15-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(a)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-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x 1f73b8b56cf35de29a433aee7bfff26cea98be3f
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025120110-deuce-arrange-e66c@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 1f73b8b56cf35de29a433aee7bfff26cea98be3f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C5=81ukasz=20Bartosik?= <ukaszb(a)chromium.org>
Date: Wed, 19 Nov 2025 21:29:09 +0000
Subject: [PATCH] xhci: dbgtty: fix device unregister
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
When DbC is disconnected then xhci_dbc_tty_unregister_device()
is called. However if there is any user space process blocked
on write to DbC terminal device then it will never be signalled
and thus stay blocked indifinitely.
This fix adds a tty_vhangup() call in xhci_dbc_tty_unregister_device().
The tty_vhangup() wakes up any blocked writers and causes subsequent
write attempts to DbC terminal device to fail.
Cc: stable <stable(a)kernel.org>
Fixes: dfba2174dc42 ("usb: xhci: Add DbC support in xHCI driver")
Signed-off-by: Łukasz Bartosik <ukaszb(a)chromium.org>
Link: https://patch.msgid.link/20251119212910.1245694-1-ukaszb@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
diff --git a/drivers/usb/host/xhci-dbgtty.c b/drivers/usb/host/xhci-dbgtty.c
index b7f95565524d..57cdda4e09c8 100644
--- a/drivers/usb/host/xhci-dbgtty.c
+++ b/drivers/usb/host/xhci-dbgtty.c
@@ -550,6 +550,12 @@ static void xhci_dbc_tty_unregister_device(struct xhci_dbc *dbc)
if (!port->registered)
return;
+ /*
+ * Hang up the TTY. This wakes up any blocked
+ * writers and causes subsequent writes to fail.
+ */
+ tty_vhangup(port->port.tty);
+
tty_unregister_device(dbc_tty_driver, port->minor);
xhci_dbc_tty_exit_port(port);
port->registered = false;
The patch below does not apply to the 6.1-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(a)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-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 2ea6190f42d0416a4310e60a7fcb0b49fcbbd4fb
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025122951-slurp-ascent-4d97@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 2ea6190f42d0416a4310e60a7fcb0b49fcbbd4fb Mon Sep 17 00:00:00 2001
From: Paolo Abeni <pabeni(a)redhat.com>
Date: Fri, 5 Dec 2025 19:55:16 +0100
Subject: [PATCH] mptcp: schedule rtx timer only after pushing data
The MPTCP protocol usually schedule the retransmission timer only
when there is some chances for such retransmissions to happen.
With a notable exception: __mptcp_push_pending() currently schedule
such timer unconditionally, potentially leading to unnecessary rtx
timer expiration.
The issue is present since the blamed commit below but become easily
reproducible after commit 27b0e701d387 ("mptcp: drop bogus optimization
in __mptcp_check_push()")
Fixes: 33d41c9cd74c ("mptcp: more accurate timeout")
Cc: stable(a)vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni(a)redhat.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe(a)kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe(a)kernel.org>
Link: https://patch.msgid.link/20251205-net-mptcp-misc-fixes-6-19-rc1-v1-3-9e4781…
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index e212c1374bd0..d8a7f7029164 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -1623,7 +1623,7 @@ void __mptcp_push_pending(struct sock *sk, unsigned int flags)
struct mptcp_sendmsg_info info = {
.flags = flags,
};
- bool do_check_data_fin = false;
+ bool copied = false;
int push_count = 1;
while (mptcp_send_head(sk) && (push_count > 0)) {
@@ -1665,7 +1665,7 @@ void __mptcp_push_pending(struct sock *sk, unsigned int flags)
push_count--;
continue;
}
- do_check_data_fin = true;
+ copied = true;
}
}
}
@@ -1674,11 +1674,14 @@ void __mptcp_push_pending(struct sock *sk, unsigned int flags)
if (ssk)
mptcp_push_release(ssk, &info);
- /* ensure the rtx timer is running */
- if (!mptcp_rtx_timer_pending(sk))
- mptcp_reset_rtx_timer(sk);
- if (do_check_data_fin)
+ /* Avoid scheduling the rtx timer if no data has been pushed; the timer
+ * will be updated on positive acks by __mptcp_cleanup_una().
+ */
+ if (copied) {
+ if (!mptcp_rtx_timer_pending(sk))
+ mptcp_reset_rtx_timer(sk);
mptcp_check_send_data_fin(sk);
+ }
}
static void __mptcp_subflow_push_pending(struct sock *sk, struct sock *ssk, bool first)
The patch below does not apply to the 5.15-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(a)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-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x 2ea6190f42d0416a4310e60a7fcb0b49fcbbd4fb
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025122952-supervise-regulate-a26b@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 2ea6190f42d0416a4310e60a7fcb0b49fcbbd4fb Mon Sep 17 00:00:00 2001
From: Paolo Abeni <pabeni(a)redhat.com>
Date: Fri, 5 Dec 2025 19:55:16 +0100
Subject: [PATCH] mptcp: schedule rtx timer only after pushing data
The MPTCP protocol usually schedule the retransmission timer only
when there is some chances for such retransmissions to happen.
With a notable exception: __mptcp_push_pending() currently schedule
such timer unconditionally, potentially leading to unnecessary rtx
timer expiration.
The issue is present since the blamed commit below but become easily
reproducible after commit 27b0e701d387 ("mptcp: drop bogus optimization
in __mptcp_check_push()")
Fixes: 33d41c9cd74c ("mptcp: more accurate timeout")
Cc: stable(a)vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni(a)redhat.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe(a)kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe(a)kernel.org>
Link: https://patch.msgid.link/20251205-net-mptcp-misc-fixes-6-19-rc1-v1-3-9e4781…
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index e212c1374bd0..d8a7f7029164 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -1623,7 +1623,7 @@ void __mptcp_push_pending(struct sock *sk, unsigned int flags)
struct mptcp_sendmsg_info info = {
.flags = flags,
};
- bool do_check_data_fin = false;
+ bool copied = false;
int push_count = 1;
while (mptcp_send_head(sk) && (push_count > 0)) {
@@ -1665,7 +1665,7 @@ void __mptcp_push_pending(struct sock *sk, unsigned int flags)
push_count--;
continue;
}
- do_check_data_fin = true;
+ copied = true;
}
}
}
@@ -1674,11 +1674,14 @@ void __mptcp_push_pending(struct sock *sk, unsigned int flags)
if (ssk)
mptcp_push_release(ssk, &info);
- /* ensure the rtx timer is running */
- if (!mptcp_rtx_timer_pending(sk))
- mptcp_reset_rtx_timer(sk);
- if (do_check_data_fin)
+ /* Avoid scheduling the rtx timer if no data has been pushed; the timer
+ * will be updated on positive acks by __mptcp_cleanup_una().
+ */
+ if (copied) {
+ if (!mptcp_rtx_timer_pending(sk))
+ mptcp_reset_rtx_timer(sk);
mptcp_check_send_data_fin(sk);
+ }
}
static void __mptcp_subflow_push_pending(struct sock *sk, struct sock *ssk, bool first)
The patch below does not apply to the 5.15-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(a)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-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x 29f4801e9c8dfd12bdcb33b61a6ac479c7162bd7
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025122947-enforced-elective-e753@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 29f4801e9c8dfd12bdcb33b61a6ac479c7162bd7 Mon Sep 17 00:00:00 2001
From: "Matthieu Baerts (NGI0)" <matttbe(a)kernel.org>
Date: Fri, 5 Dec 2025 19:55:15 +0100
Subject: [PATCH] selftests: mptcp: pm: ensure unknown flags are ignored
This validates the previous commit: the userspace can set unknown flags
-- the 7th bit is currently unused -- without errors, but only the
supported ones are printed in the endpoints dumps.
The 'Fixes' tag here below is the same as the one from the previous
commit: this patch here is not fixing anything wrong in the selftests,
but it validates the previous fix for an issue introduced by this commit
ID.
Fixes: 01cacb00b35c ("mptcp: add netlink-based PM")
Cc: stable(a)vger.kernel.org
Reviewed-by: Mat Martineau <martineau(a)kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe(a)kernel.org>
Link: https://patch.msgid.link/20251205-net-mptcp-misc-fixes-6-19-rc1-v1-2-9e4781…
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
diff --git a/tools/testing/selftests/net/mptcp/pm_netlink.sh b/tools/testing/selftests/net/mptcp/pm_netlink.sh
index ec6a87588191..123d9d7a0278 100755
--- a/tools/testing/selftests/net/mptcp/pm_netlink.sh
+++ b/tools/testing/selftests/net/mptcp/pm_netlink.sh
@@ -192,6 +192,10 @@ check "show_endpoints" \
flush_endpoint
check "show_endpoints" "" "flush addrs"
+add_endpoint 10.0.1.1 flags unknown
+check "show_endpoints" "$(format_endpoints "1,10.0.1.1")" "ignore unknown flags"
+flush_endpoint
+
set_limits 9 1 2>/dev/null
check "get_limits" "${default_limits}" "rcv addrs above hard limit"
diff --git a/tools/testing/selftests/net/mptcp/pm_nl_ctl.c b/tools/testing/selftests/net/mptcp/pm_nl_ctl.c
index 65b374232ff5..99eecccbf0c8 100644
--- a/tools/testing/selftests/net/mptcp/pm_nl_ctl.c
+++ b/tools/testing/selftests/net/mptcp/pm_nl_ctl.c
@@ -24,6 +24,8 @@
#define IPPROTO_MPTCP 262
#endif
+#define MPTCP_PM_ADDR_FLAG_UNKNOWN _BITUL(7)
+
static void syntax(char *argv[])
{
fprintf(stderr, "%s add|ann|rem|csf|dsf|get|set|del|flush|dump|events|listen|accept [<args>]\n", argv[0]);
@@ -836,6 +838,8 @@ int add_addr(int fd, int pm_family, int argc, char *argv[])
flags |= MPTCP_PM_ADDR_FLAG_BACKUP;
else if (!strcmp(tok, "fullmesh"))
flags |= MPTCP_PM_ADDR_FLAG_FULLMESH;
+ else if (!strcmp(tok, "unknown"))
+ flags |= MPTCP_PM_ADDR_FLAG_UNKNOWN;
else
error(1, errno,
"unknown flag %s", argv[arg]);
@@ -1048,6 +1052,13 @@ static void print_addr(struct rtattr *attrs, int len)
printf(",");
}
+ if (flags & MPTCP_PM_ADDR_FLAG_UNKNOWN) {
+ printf("unknown");
+ flags &= ~MPTCP_PM_ADDR_FLAG_UNKNOWN;
+ if (flags)
+ printf(",");
+ }
+
/* bump unknown flags, if any */
if (flags)
printf("0x%x", flags);
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 <stable(a)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-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x 29f4801e9c8dfd12bdcb33b61a6ac479c7162bd7
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025122947-clapping-zookeeper-5d32@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 29f4801e9c8dfd12bdcb33b61a6ac479c7162bd7 Mon Sep 17 00:00:00 2001
From: "Matthieu Baerts (NGI0)" <matttbe(a)kernel.org>
Date: Fri, 5 Dec 2025 19:55:15 +0100
Subject: [PATCH] selftests: mptcp: pm: ensure unknown flags are ignored
This validates the previous commit: the userspace can set unknown flags
-- the 7th bit is currently unused -- without errors, but only the
supported ones are printed in the endpoints dumps.
The 'Fixes' tag here below is the same as the one from the previous
commit: this patch here is not fixing anything wrong in the selftests,
but it validates the previous fix for an issue introduced by this commit
ID.
Fixes: 01cacb00b35c ("mptcp: add netlink-based PM")
Cc: stable(a)vger.kernel.org
Reviewed-by: Mat Martineau <martineau(a)kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe(a)kernel.org>
Link: https://patch.msgid.link/20251205-net-mptcp-misc-fixes-6-19-rc1-v1-2-9e4781…
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
diff --git a/tools/testing/selftests/net/mptcp/pm_netlink.sh b/tools/testing/selftests/net/mptcp/pm_netlink.sh
index ec6a87588191..123d9d7a0278 100755
--- a/tools/testing/selftests/net/mptcp/pm_netlink.sh
+++ b/tools/testing/selftests/net/mptcp/pm_netlink.sh
@@ -192,6 +192,10 @@ check "show_endpoints" \
flush_endpoint
check "show_endpoints" "" "flush addrs"
+add_endpoint 10.0.1.1 flags unknown
+check "show_endpoints" "$(format_endpoints "1,10.0.1.1")" "ignore unknown flags"
+flush_endpoint
+
set_limits 9 1 2>/dev/null
check "get_limits" "${default_limits}" "rcv addrs above hard limit"
diff --git a/tools/testing/selftests/net/mptcp/pm_nl_ctl.c b/tools/testing/selftests/net/mptcp/pm_nl_ctl.c
index 65b374232ff5..99eecccbf0c8 100644
--- a/tools/testing/selftests/net/mptcp/pm_nl_ctl.c
+++ b/tools/testing/selftests/net/mptcp/pm_nl_ctl.c
@@ -24,6 +24,8 @@
#define IPPROTO_MPTCP 262
#endif
+#define MPTCP_PM_ADDR_FLAG_UNKNOWN _BITUL(7)
+
static void syntax(char *argv[])
{
fprintf(stderr, "%s add|ann|rem|csf|dsf|get|set|del|flush|dump|events|listen|accept [<args>]\n", argv[0]);
@@ -836,6 +838,8 @@ int add_addr(int fd, int pm_family, int argc, char *argv[])
flags |= MPTCP_PM_ADDR_FLAG_BACKUP;
else if (!strcmp(tok, "fullmesh"))
flags |= MPTCP_PM_ADDR_FLAG_FULLMESH;
+ else if (!strcmp(tok, "unknown"))
+ flags |= MPTCP_PM_ADDR_FLAG_UNKNOWN;
else
error(1, errno,
"unknown flag %s", argv[arg]);
@@ -1048,6 +1052,13 @@ static void print_addr(struct rtattr *attrs, int len)
printf(",");
}
+ if (flags & MPTCP_PM_ADDR_FLAG_UNKNOWN) {
+ printf("unknown");
+ flags &= ~MPTCP_PM_ADDR_FLAG_UNKNOWN;
+ if (flags)
+ printf(",");
+ }
+
/* bump unknown flags, if any */
if (flags)
printf("0x%x", flags);
The patch below does not apply to the 6.6-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(a)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-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 29f4801e9c8dfd12bdcb33b61a6ac479c7162bd7
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025122946-puppet-visiting-41e4@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 29f4801e9c8dfd12bdcb33b61a6ac479c7162bd7 Mon Sep 17 00:00:00 2001
From: "Matthieu Baerts (NGI0)" <matttbe(a)kernel.org>
Date: Fri, 5 Dec 2025 19:55:15 +0100
Subject: [PATCH] selftests: mptcp: pm: ensure unknown flags are ignored
This validates the previous commit: the userspace can set unknown flags
-- the 7th bit is currently unused -- without errors, but only the
supported ones are printed in the endpoints dumps.
The 'Fixes' tag here below is the same as the one from the previous
commit: this patch here is not fixing anything wrong in the selftests,
but it validates the previous fix for an issue introduced by this commit
ID.
Fixes: 01cacb00b35c ("mptcp: add netlink-based PM")
Cc: stable(a)vger.kernel.org
Reviewed-by: Mat Martineau <martineau(a)kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe(a)kernel.org>
Link: https://patch.msgid.link/20251205-net-mptcp-misc-fixes-6-19-rc1-v1-2-9e4781…
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
diff --git a/tools/testing/selftests/net/mptcp/pm_netlink.sh b/tools/testing/selftests/net/mptcp/pm_netlink.sh
index ec6a87588191..123d9d7a0278 100755
--- a/tools/testing/selftests/net/mptcp/pm_netlink.sh
+++ b/tools/testing/selftests/net/mptcp/pm_netlink.sh
@@ -192,6 +192,10 @@ check "show_endpoints" \
flush_endpoint
check "show_endpoints" "" "flush addrs"
+add_endpoint 10.0.1.1 flags unknown
+check "show_endpoints" "$(format_endpoints "1,10.0.1.1")" "ignore unknown flags"
+flush_endpoint
+
set_limits 9 1 2>/dev/null
check "get_limits" "${default_limits}" "rcv addrs above hard limit"
diff --git a/tools/testing/selftests/net/mptcp/pm_nl_ctl.c b/tools/testing/selftests/net/mptcp/pm_nl_ctl.c
index 65b374232ff5..99eecccbf0c8 100644
--- a/tools/testing/selftests/net/mptcp/pm_nl_ctl.c
+++ b/tools/testing/selftests/net/mptcp/pm_nl_ctl.c
@@ -24,6 +24,8 @@
#define IPPROTO_MPTCP 262
#endif
+#define MPTCP_PM_ADDR_FLAG_UNKNOWN _BITUL(7)
+
static void syntax(char *argv[])
{
fprintf(stderr, "%s add|ann|rem|csf|dsf|get|set|del|flush|dump|events|listen|accept [<args>]\n", argv[0]);
@@ -836,6 +838,8 @@ int add_addr(int fd, int pm_family, int argc, char *argv[])
flags |= MPTCP_PM_ADDR_FLAG_BACKUP;
else if (!strcmp(tok, "fullmesh"))
flags |= MPTCP_PM_ADDR_FLAG_FULLMESH;
+ else if (!strcmp(tok, "unknown"))
+ flags |= MPTCP_PM_ADDR_FLAG_UNKNOWN;
else
error(1, errno,
"unknown flag %s", argv[arg]);
@@ -1048,6 +1052,13 @@ static void print_addr(struct rtattr *attrs, int len)
printf(",");
}
+ if (flags & MPTCP_PM_ADDR_FLAG_UNKNOWN) {
+ printf("unknown");
+ flags &= ~MPTCP_PM_ADDR_FLAG_UNKNOWN;
+ if (flags)
+ printf(",");
+ }
+
/* bump unknown flags, if any */
if (flags)
printf("0x%x", flags);
The patch below does not apply to the 6.1-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(a)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-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 29f4801e9c8dfd12bdcb33b61a6ac479c7162bd7
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025122946-wharf-satin-c518@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 29f4801e9c8dfd12bdcb33b61a6ac479c7162bd7 Mon Sep 17 00:00:00 2001
From: "Matthieu Baerts (NGI0)" <matttbe(a)kernel.org>
Date: Fri, 5 Dec 2025 19:55:15 +0100
Subject: [PATCH] selftests: mptcp: pm: ensure unknown flags are ignored
This validates the previous commit: the userspace can set unknown flags
-- the 7th bit is currently unused -- without errors, but only the
supported ones are printed in the endpoints dumps.
The 'Fixes' tag here below is the same as the one from the previous
commit: this patch here is not fixing anything wrong in the selftests,
but it validates the previous fix for an issue introduced by this commit
ID.
Fixes: 01cacb00b35c ("mptcp: add netlink-based PM")
Cc: stable(a)vger.kernel.org
Reviewed-by: Mat Martineau <martineau(a)kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe(a)kernel.org>
Link: https://patch.msgid.link/20251205-net-mptcp-misc-fixes-6-19-rc1-v1-2-9e4781…
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
diff --git a/tools/testing/selftests/net/mptcp/pm_netlink.sh b/tools/testing/selftests/net/mptcp/pm_netlink.sh
index ec6a87588191..123d9d7a0278 100755
--- a/tools/testing/selftests/net/mptcp/pm_netlink.sh
+++ b/tools/testing/selftests/net/mptcp/pm_netlink.sh
@@ -192,6 +192,10 @@ check "show_endpoints" \
flush_endpoint
check "show_endpoints" "" "flush addrs"
+add_endpoint 10.0.1.1 flags unknown
+check "show_endpoints" "$(format_endpoints "1,10.0.1.1")" "ignore unknown flags"
+flush_endpoint
+
set_limits 9 1 2>/dev/null
check "get_limits" "${default_limits}" "rcv addrs above hard limit"
diff --git a/tools/testing/selftests/net/mptcp/pm_nl_ctl.c b/tools/testing/selftests/net/mptcp/pm_nl_ctl.c
index 65b374232ff5..99eecccbf0c8 100644
--- a/tools/testing/selftests/net/mptcp/pm_nl_ctl.c
+++ b/tools/testing/selftests/net/mptcp/pm_nl_ctl.c
@@ -24,6 +24,8 @@
#define IPPROTO_MPTCP 262
#endif
+#define MPTCP_PM_ADDR_FLAG_UNKNOWN _BITUL(7)
+
static void syntax(char *argv[])
{
fprintf(stderr, "%s add|ann|rem|csf|dsf|get|set|del|flush|dump|events|listen|accept [<args>]\n", argv[0]);
@@ -836,6 +838,8 @@ int add_addr(int fd, int pm_family, int argc, char *argv[])
flags |= MPTCP_PM_ADDR_FLAG_BACKUP;
else if (!strcmp(tok, "fullmesh"))
flags |= MPTCP_PM_ADDR_FLAG_FULLMESH;
+ else if (!strcmp(tok, "unknown"))
+ flags |= MPTCP_PM_ADDR_FLAG_UNKNOWN;
else
error(1, errno,
"unknown flag %s", argv[arg]);
@@ -1048,6 +1052,13 @@ static void print_addr(struct rtattr *attrs, int len)
printf(",");
}
+ if (flags & MPTCP_PM_ADDR_FLAG_UNKNOWN) {
+ printf("unknown");
+ flags &= ~MPTCP_PM_ADDR_FLAG_UNKNOWN;
+ if (flags)
+ printf(",");
+ }
+
/* bump unknown flags, if any */
if (flags)
printf("0x%x", flags);
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(a)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 29f4801e9c8dfd12bdcb33b61a6ac479c7162bd7
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025122945-litigator-machinist-2f66@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 29f4801e9c8dfd12bdcb33b61a6ac479c7162bd7 Mon Sep 17 00:00:00 2001
From: "Matthieu Baerts (NGI0)" <matttbe(a)kernel.org>
Date: Fri, 5 Dec 2025 19:55:15 +0100
Subject: [PATCH] selftests: mptcp: pm: ensure unknown flags are ignored
This validates the previous commit: the userspace can set unknown flags
-- the 7th bit is currently unused -- without errors, but only the
supported ones are printed in the endpoints dumps.
The 'Fixes' tag here below is the same as the one from the previous
commit: this patch here is not fixing anything wrong in the selftests,
but it validates the previous fix for an issue introduced by this commit
ID.
Fixes: 01cacb00b35c ("mptcp: add netlink-based PM")
Cc: stable(a)vger.kernel.org
Reviewed-by: Mat Martineau <martineau(a)kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe(a)kernel.org>
Link: https://patch.msgid.link/20251205-net-mptcp-misc-fixes-6-19-rc1-v1-2-9e4781…
Signed-off-by: Jakub Kicinski <kuba(a)kernel.org>
diff --git a/tools/testing/selftests/net/mptcp/pm_netlink.sh b/tools/testing/selftests/net/mptcp/pm_netlink.sh
index ec6a87588191..123d9d7a0278 100755
--- a/tools/testing/selftests/net/mptcp/pm_netlink.sh
+++ b/tools/testing/selftests/net/mptcp/pm_netlink.sh
@@ -192,6 +192,10 @@ check "show_endpoints" \
flush_endpoint
check "show_endpoints" "" "flush addrs"
+add_endpoint 10.0.1.1 flags unknown
+check "show_endpoints" "$(format_endpoints "1,10.0.1.1")" "ignore unknown flags"
+flush_endpoint
+
set_limits 9 1 2>/dev/null
check "get_limits" "${default_limits}" "rcv addrs above hard limit"
diff --git a/tools/testing/selftests/net/mptcp/pm_nl_ctl.c b/tools/testing/selftests/net/mptcp/pm_nl_ctl.c
index 65b374232ff5..99eecccbf0c8 100644
--- a/tools/testing/selftests/net/mptcp/pm_nl_ctl.c
+++ b/tools/testing/selftests/net/mptcp/pm_nl_ctl.c
@@ -24,6 +24,8 @@
#define IPPROTO_MPTCP 262
#endif
+#define MPTCP_PM_ADDR_FLAG_UNKNOWN _BITUL(7)
+
static void syntax(char *argv[])
{
fprintf(stderr, "%s add|ann|rem|csf|dsf|get|set|del|flush|dump|events|listen|accept [<args>]\n", argv[0]);
@@ -836,6 +838,8 @@ int add_addr(int fd, int pm_family, int argc, char *argv[])
flags |= MPTCP_PM_ADDR_FLAG_BACKUP;
else if (!strcmp(tok, "fullmesh"))
flags |= MPTCP_PM_ADDR_FLAG_FULLMESH;
+ else if (!strcmp(tok, "unknown"))
+ flags |= MPTCP_PM_ADDR_FLAG_UNKNOWN;
else
error(1, errno,
"unknown flag %s", argv[arg]);
@@ -1048,6 +1052,13 @@ static void print_addr(struct rtattr *attrs, int len)
printf(",");
}
+ if (flags & MPTCP_PM_ADDR_FLAG_UNKNOWN) {
+ printf("unknown");
+ flags &= ~MPTCP_PM_ADDR_FLAG_UNKNOWN;
+ if (flags)
+ printf(",");
+ }
+
/* bump unknown flags, if any */
if (flags)
printf("0x%x", flags);