This is a note to let you know that I've just added the patch titled
net: restrict SO_REUSEPORT to inet sockets
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-restrict-so_reuseport-to-inet-sockets.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit ae090c47bc8c84e25ec16e76e49ac5df0024f6ca
Author: Eric Dumazet <edumazet@xxxxxxxxxx>
Date: Tue Dec 31 16:05:27 2024 +0000
net: restrict SO_REUSEPORT to inet sockets
[ Upstream commit 5b0af621c3f6ef9261cf6067812f2fd9943acb4b ]
After blamed commit, crypto sockets could accidentally be destroyed
from RCU call back, as spotted by zyzbot [1].
Trying to acquire a mutex in RCU callback is not allowed.
Restrict SO_REUSEPORT socket option to inet sockets.
v1 of this patch supported TCP, UDP and SCTP sockets,
but fcnal-test.sh test needed RAW and ICMP support.
[1]
BUG: sleeping function called from invalid context at kernel/locking/mutex.c:562
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 24, name: ksoftirqd/1
preempt_count: 100, expected: 0
RCU nest depth: 0, expected: 0
1 lock held by ksoftirqd/1/24:
#0: ffffffff8e937ba0 (rcu_callback){....}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8e937ba0 (rcu_callback){....}-{0:0}, at: rcu_do_batch kernel/rcu/tree.c:2561 [inline]
#0: ffffffff8e937ba0 (rcu_callback){....}-{0:0}, at: rcu_core+0xa37/0x17a0 kernel/rcu/tree.c:2823
Preemption disabled at:
[<ffffffff8161c8c8>] softirq_handle_begin kernel/softirq.c:402 [inline]
[<ffffffff8161c8c8>] handle_softirqs+0x128/0x9b0 kernel/softirq.c:537
CPU: 1 UID: 0 PID: 24 Comm: ksoftirqd/1 Not tainted 6.13.0-rc3-syzkaller-00174-ga024e377efed #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
__might_resched+0x5d4/0x780 kernel/sched/core.c:8758
__mutex_lock_common kernel/locking/mutex.c:562 [inline]
__mutex_lock+0x131/0xee0 kernel/locking/mutex.c:735
crypto_put_default_null_skcipher+0x18/0x70 crypto/crypto_null.c:179
aead_release+0x3d/0x50 crypto/algif_aead.c:489
alg_do_release crypto/af_alg.c:118 [inline]
alg_sock_destruct+0x86/0xc0 crypto/af_alg.c:502
__sk_destruct+0x58/0x5f0 net/core/sock.c:2260
rcu_do_batch kernel/rcu/tree.c:2567 [inline]
rcu_core+0xaaa/0x17a0 kernel/rcu/tree.c:2823
handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561
run_ksoftirqd+0xca/0x130 kernel/softirq.c:950
smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Fixes: 8c7138b33e5c ("net: Unpublish sk from sk_reuseport_cb before call_rcu")
Reported-by: syzbot+b3e02953598f447d4d2a@xxxxxxxxxxxxxxxxxxxxxxxxx
Closes: https://lore.kernel.org/netdev/6772f2f4.050a0220.2f3838.04cb.GAE@xxxxxxxxxx/T/#u
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Cc: Martin KaFai Lau <kafai@xxxxxx>
Reviewed-by: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx>
Link: https://patch.msgid.link/20241231160527.3994168-1-edumazet@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/core/sock.c b/net/core/sock.c
index bc2a4e38dcea..84ba3f67bca9 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1133,7 +1133,10 @@ int sk_setsockopt(struct sock *sk, int level, int optname,
sk->sk_reuse = (valbool ? SK_CAN_REUSE : SK_NO_REUSE);
break;
case SO_REUSEPORT:
- sk->sk_reuseport = valbool;
+ if (valbool && !sk_is_inet(sk))
+ ret = -EOPNOTSUPP;
+ else
+ sk->sk_reuseport = valbool;
break;
case SO_TYPE:
case SO_PROTOCOL:
