cbcvebase.
CVE-2024-56642
published 2024-12-27

CVE-2024-56642: In the Linux kernel, the following vulnerability has been resolved: tipc: Fix use-after-free of kernel socket in cleanup_bearer(). syzkaller reported a…

PriorityP339high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.24%
15.6th percentile
In the Linux kernel, the following vulnerability has been resolved: tipc: Fix use-after-free of kernel socket in cleanup_bearer(). syzkaller reported a use-after-free of UDP kernel socket in cleanup_bearer() without repro. [0][1] When bearer_disable() calls tipc_udp_disable(), cleanup of the UDP kernel socket is deferred by work calling cleanup_bearer(). tipc_exit_net() waits for such works to finish by checking tipc_net(net)->wq_count. However, the work decrements the count too early before releasing the kernel socket, unblocking cleanup_net() and resulting in use-after-free. Let's move the decrement after releasing the socket in cleanup_bearer(). [0]: ref_tracker: net notrefcnt@000000009b3d1faf has 1/1 users at sk_alloc+0x438/0x608 inet_create+0x4c8/0xcb0 __sock_create+0x350/0x6b8 sock_create_kern+0x58/0x78 udp_sock_create4+0x68/0x398 udp_sock_create+0x88/0xc8 tipc_udp_enable+0x5e8/0x848 __tipc_nl_bearer_enable+0x84c/0xed8 tipc_nl_bearer_enable+0x38/0x60 genl_family_rcv_msg_doit+0x170/0x248 genl_rcv_msg+0x400/0x5b0 netlink_rcv_skb+0x1dc/0x398 genl_rcv+0x44/0x68 netlink_unicast+0x678/0x8b0 netlink_sendmsg+0x5e4/0x898 ____sys_sendmsg+0x500/0x830 [1]: BUG: KMSAN: use-after-free in udp_hashslot include/net/udp.h:85 [inline] BUG: KMSAN: use-after-free in udp_lib_unhash+0x3b8/0x930 net/ipv4/udp.c:1979 udp_hashslot include/net/udp.h:85 [inline] udp_lib_unhash+0x3b8/0x930 net/ipv4/udp.c:1979 sk_common_release+0xaf/0x3f0 net/core/sock.c:3820 inet_release+0x1e0/0x260 net/ipv4/af_inet.c:437 inet6_release+0x6f/0xd0 net/ipv6/af_inet6.c:489 __sock_release net/socket.c:658 [inline] sock_release+0xa0/0x210 net/socket.c:686 cleanup_bearer+0x42d/0x4c0 net/tipc/udp_media.c:819 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xcaf/0x1c90 kernel/workqueue.c:3310 worker_thread+0xf6c/0x1510 kernel/workqueue.c:3391 kthread+0x531/0x6b0 kernel/kthread.c:389 ret_from_fork+0x60/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entr

Affected

34 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.123-1 (bookworm)linux 6.1.123-1 (bookworm)
debianlinux-6.1< linux 6.1.123-1 (bookworm)linux 6.1.123-1 (bookworm)
linuxlinux
linuxlinux
linuxlinux>= 04c26faa51d1e2fe71cf13c45791f5174c37f986 < d2a4894f238551eae178904e7f45af87577074fdd2a4894f238551eae178904e7f45af87577074fd
linuxlinux>= 04c26faa51d1e2fe71cf13c45791f5174c37f986 < d62d5180c036eeac09f80660edc7a602b369125fd62d5180c036eeac09f80660edc7a602b369125f
linuxlinux>= 04c26faa51d1e2fe71cf13c45791f5174c37f986 < d00d4470bf8c4282617a3a10e76b20a9c7e4cffad00d4470bf8c4282617a3a10e76b20a9c7e4cffa
linuxlinux>= 04c26faa51d1e2fe71cf13c45791f5174c37f986 < e48b211c4c59062cb6dd6c2c37c51a7cc235a464e48b211c4c59062cb6dd6c2c37c51a7cc235a464
linuxlinux>= 04c26faa51d1e2fe71cf13c45791f5174c37f986 < 6a2fa13312e51a621f652d522d7e2df7066330b66a2fa13312e51a621f652d522d7e2df7066330b6
linuxlinux>= 5.10.42 < 5.10.2315.10.231
linuxlinux>= 5.12.9 < 5.135.13
linuxlinux>= 5.4.124 < 5.4.2875.4.287
linuxlinux>= 5195ec5e365a2a9331bfeb585b613a6e94f98dba < 650ee9a22d7a2de8999fac2d45983597a0c22359650ee9a22d7a2de8999fac2d45983597a0c22359
linuxlinux>= d1f76dfadaf8f47ed1753f97dbcbd41c16215ffa < 4e69457f9dfae67435f3ccf29008768eae8604154e69457f9dfae67435f3ccf29008768eae860415
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.234-15.10.234-1
linuxlinux_kernel>= 0 < 6.1.123-16.1.123-1
linuxlinux_kernel>= 0 < 6.12.5-16.12.5-1
linuxlinux_kernel>= 0 < 6.12.5-16.12.5-1
linuxlinux_kernel>= 0 < 5.4.0-211.2315.4.0-211.231
linuxlinux_kernel>= 0 < 5.15.0-135.1465.15.0-135.146
linuxlinux_kernel>= 0 < 6.8.0-58.606.8.0-58.60
linuxlinux_kernel>= 0 < 4.4.0-268.3024.4.0-268.302
linuxlinux_kernel>= 0 < 4.15.0-237.2494.15.0-237.249
linuxlinux_kernel>= 4.2 < 5.4.2875.4.287

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv8.8HIGH
vendor_ubuntu8.8HIGH
vendor_debian7.8HIGH
vendor_msrc7.8HIGH
vendor_redhat7.8HIGH
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