In the Linux kernel, the following vulnerability has been resolved:
net: restrict SO_REUSEPORT to inet sockets
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 inatomic(): 1, irqsdisabled(): 0, nonblock: 0, pid: 24, name: ksoftirqd/1 preemptcount: 100, expected: 0 RCU nest depth: 0, expected: 0 1 lock held by ksoftirqd/1/24: #0: ffffffff8e937ba0 (rcucallback){....}-{0:0}, at: rculockacquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937ba0 (rcucallback){....}-{0:0}, at: rcudobatch kernel/rcu/tree.c:2561 [inline] #0: ffffffff8e937ba0 (rcucallback){....}-{0:0}, at: rcucore+0xa37/0x17a0 kernel/rcu/tree.c:2823 Preemption disabled at: [<ffffffff8161c8c8>] softirqhandlebegin kernel/softirq.c:402 [inline] [<ffffffff8161c8c8>] handlesoftirqs+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> _dumpstack lib/dumpstack.c:94 [inline] dumpstacklvl+0x241/0x360 lib/dumpstack.c:120 _mightresched+0x5d4/0x780 kernel/sched/core.c:8758 _mutexlockcommon kernel/locking/mutex.c:562 [inline] _mutexlock+0x131/0xee0 kernel/locking/mutex.c:735 cryptoputdefaultnullskcipher+0x18/0x70 crypto/cryptonull.c:179 aeadrelease+0x3d/0x50 crypto/algifaead.c:489 algdorelease crypto/afalg.c:118 [inline] algsockdestruct+0x86/0xc0 crypto/afalg.c:502 _skdestruct+0x58/0x5f0 net/core/sock.c:2260 rcudobatch kernel/rcu/tree.c:2567 [inline] rcucore+0xaaa/0x17a0 kernel/rcu/tree.c:2823 handlesoftirqs+0x2d4/0x9b0 kernel/softirq.c:561 runksoftirqd+0xca/0x130 kernel/softirq.c:950 smpbootthreadfn+0x544/0xa30 kernel/smpboot.c:164 kthread+0x2f0/0x390 kernel/kthread.c:389 retfromfork+0x4b/0x80 arch/x86/kernel/process.c:147 retfromforkasm+0x1a/0x30 arch/x86/entry/entry64.S:244 </TASK>