cbcvebase.
CVE-2025-22077
published 2025-04-16

CVE-2025-22077: In the Linux kernel, the following vulnerability has been resolved: Revert "smb: client: fix TCP timers deadlock after rmmod" This reverts commit…

PriorityP422medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.35%
27.2th percentile
In the Linux kernel, the following vulnerability has been resolved: Revert "smb: client: fix TCP timers deadlock after rmmod" This reverts commit e9f2517a3e18a54a3943c098d2226b245d488801. Commit e9f2517a3e18 ("smb: client: fix TCP timers deadlock after rmmod") is intended to fix a null-ptr-deref in LOCKDEP, which is mentioned as CVE-2024-54680, but is actually did not fix anything; The issue can be reproduced on top of it. [0] Also, it reverted the change by commit ef7134c7fc48 ("smb: client: Fix use-after-free of network namespace.") and introduced a real issue by reviving the kernel TCP socket. When a reconnect happens for a CIFS connection, the socket state transitions to FIN_WAIT_1. Then, inet_csk_clear_xmit_timers_sync() in tcp_close() stops all timers for the socket. If an incoming FIN packet is lost, the socket will stay at FIN_WAIT_1 forever, and such sockets could be leaked up to net.ipv4.tcp_max_orphans. Usually, FIN can be retransmitted by the peer, but if the peer aborts the connection, the issue comes into reality. I warned about this privately by pointing out the exact report [1], but the bogus fix was finally merged. So, we should not stop the timers to finally kill the connection on our side in that case, meaning we must not use a kernel socket for TCP whose sk->sk_net_refcnt is 0. The kernel socket does not have a reference to its netns to make it possible to tear down netns without cleaning up every resource in it. For example, tunnel devices use a UDP socket internally, but we can destroy netns without removing such devices and let it complete during exit. Otherwise, netns would be leaked when the last application died. However, this is problematic for TCP sockets because TCP has timers to close the connection gracefully even after the socket is close()d. The lifetime of the socket and its netns is different from the lifetime of the underlying connection. If the socket user does not maintain the netns lifetime, the timer could be fire

Affected

20 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.12.25-1 (forky)linux 6.12.25-1 (forky)
linuxlinux
linuxlinux>= 127e907e11ccd54b59bb78fc22c43ccb76c71079 < f761eeefd531e6550cd3a5c047835b4892acb00df761eeefd531e6550cd3a5c047835b4892acb00d
linuxlinux>= 6.12.7 < 6.12.256.12.25
linuxlinux>= 6.6.68 < 6.6.886.6.88
linuxlinux>= 906807c734ed219dcb2e7bbfde5c4168ed72a3d0 < 8dbf060480236877703bff0106fc984576184d118dbf060480236877703bff0106fc984576184d11
linuxlinux>= e9f2517a3e18a54a3943c098d2226b245d488801 < 4b6f6bf1bde8d6045c389fda8d21c304dfe493844b6f6bf1bde8d6045c389fda8d21c304dfe49384
linuxlinux>= e9f2517a3e18a54a3943c098d2226b245d488801 < 95d2b9f693ff2a1180a23d7d59acc0c4e72f4c4195d2b9f693ff2a1180a23d7d59acc0c4e72f4c41
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.12.25-16.12.25-1
linuxlinux_kernel>= 0 < 6.12.25-16.12.25-1
linuxlinux_kernel>= 6.12.7 < 6.12.256.12.25
linuxlinux_kernel>= 6.13.1 < 6.14.46.14.4
linuxlinux_kernel>= 6.6.68 < 6.6.886.6.88

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5LOW
vendor_redhat5.5MEDIUM
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