cbcvebase.
CVE-2021-4454
published 2025-03-27

CVE-2021-4454: In the Linux kernel, the following vulnerability has been resolved: can: j1939: fix errant WARN_ON_ONCE in j1939_session_deactivate The conclusion…

PriorityP420medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.55%
42.7th percentile
In the Linux kernel, the following vulnerability has been resolved: can: j1939: fix errant WARN_ON_ONCE in j1939_session_deactivate The conclusion "j1939_session_deactivate() should be called with a session ref-count of at least 2" is incorrect. In some concurrent scenarios, j1939_session_deactivate can be called with the session ref-count less than 2. But there is not any problem because it will check the session active state before session putting in j1939_session_deactivate_locked(). Here is the concurrent scenario of the problem reported by syzbot and my reproduction log. cpu0 cpu1 j1939_xtp_rx_eoma j1939_xtp_rx_abort_one j1939_session_get_by_addr [kref == 2] j1939_session_get_by_addr [kref == 3] j1939_session_deactivate [kref == 2] j1939_session_put [kref == 1] j1939_session_completed j1939_session_deactivate WARN_ON_ONCE(kref < 2) WARNING: CPU: 1 PID: 21 at net/can/j1939/transport.c:1088 j1939_session_deactivate+0x5f/0x70 CPU: 1 PID: 21 Comm: ksoftirqd/1 Not tainted 5.14.0-rc7+ #32 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1 04/01/2014 RIP: 0010:j1939_session_deactivate+0x5f/0x70 Call Trace: j1939_session_deactivate_activate_next+0x11/0x28 j1939_xtp_rx_eoma+0x12a/0x180 j1939_tp_recv+0x4a2/0x510 j1939_can_recv+0x226/0x380 can_rcv_filter+0xf8/0x220 can_receive+0x102/0x220 ? process_backlog+0xf0/0x2c0 can_rcv+0x53/0xf0 __netif_receive_skb_one_core+0x67/0x90 ? process_backlog+0x97/0x2c0 __netif_receive_skb+0x22/0x80

Affected

31 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.11-1 (bookworm)linux 6.1.11-1 (bookworm)
linuxlinux
linuxlinux
linuxlinux>= 0c71437dd50dd687c15d8ca80b3b68f10bb21d63 < 9ab896775f98ff54b68512f345eed178bf9610849ab896775f98ff54b68512f345eed178bf961084
linuxlinux>= 0c71437dd50dd687c15d8ca80b3b68f10bb21d63 < 1740a1e45eee65099a92fb502e1e67e63aad277d1740a1e45eee65099a92fb502e1e67e63aad277d
linuxlinux>= 0c71437dd50dd687c15d8ca80b3b68f10bb21d63 < d0553680f94c49bbe0e39eb50d033ba563b4212dd0553680f94c49bbe0e39eb50d033ba563b4212d
linuxlinux>= 5.10.56 < 5.10.1685.10.168
linuxlinux>= 5.13.8 < 5.145.14
linuxlinux>= 5.4.138 < 5.4.2325.4.232
linuxlinux>= 55dd22c5d029423f513fd849e633adf0e9c10d0c < b6d44072117bba057d50f7a2f96e5d070c65926db6d44072117bba057d50f7a2f96e5d070c65926d
linuxlinux>= 7eef18c0479ba5d9f54fba30cd77c233ebca3eb1 < 6950df42a03c9ac9290503ced3f371199cb68fa96950df42a03c9ac9290503ced3f371199cb68fa9
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.178-15.10.178-1
linuxlinux_kernel>= 0 < 6.1.11-16.1.11-1
linuxlinux_kernel>= 0 < 6.1.11-16.1.11-1

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_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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