cbcvebase.
CVE-2025-21806
published 2025-02-27

CVE-2025-21806: In the Linux kernel, the following vulnerability has been resolved: net: let net.core.dev_weight always be non-zero The following problem was encountered…

PriorityP420medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.20%
10.2th percentile
In the Linux kernel, the following vulnerability has been resolved: net: let net.core.dev_weight always be non-zero The following problem was encountered during stability test: (NULL net_device): NAPI poll function process_backlog+0x0/0x530 \ returned 1, exceeding its budget of 0. ------------[ cut here ]------------ list_add double add: new=ffff88905f746f48, prev=ffff88905f746f48, \ next=ffff88905f746e40. WARNING: CPU: 18 PID: 5462 at lib/list_debug.c:35 \ __list_add_valid_or_report+0xf3/0x130 CPU: 18 UID: 0 PID: 5462 Comm: ping Kdump: loaded Not tainted 6.13.0-rc7+ RIP: 0010:__list_add_valid_or_report+0xf3/0x130 Call Trace: ? __warn+0xcd/0x250 ? __list_add_valid_or_report+0xf3/0x130 enqueue_to_backlog+0x923/0x1070 netif_rx_internal+0x92/0x2b0 __netif_rx+0x15/0x170 loopback_xmit+0x2ef/0x450 dev_hard_start_xmit+0x103/0x490 __dev_queue_xmit+0xeac/0x1950 ip_finish_output2+0x6cc/0x1620 ip_output+0x161/0x270 ip_push_pending_frames+0x155/0x1a0 raw_sendmsg+0xe13/0x1550 __sys_sendto+0x3bf/0x4e0 __x64_sys_sendto+0xdc/0x1b0 do_syscall_64+0x5b/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e The reproduction command is as follows: sysctl -w net.core.dev_weight=0 ping 127.0.0.1 This is because when the napi's weight is set to 0, process_backlog() may return 0 and clear the NAPI_STATE_SCHED bit of napi->state, causing this napi to be re-polled in net_rx_action() until __do_softirq() times out. Since the NAPI_STATE_SCHED bit has been cleared, napi_schedule_rps() can be retriggered in enqueue_to_backlog(), causing this issue. Making the napi's weight always non-zero solves this problem. Triggering this issue requires system-wide admin (setting is not namespaced).

Affected

26 ranges· showing 25
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.129-1 (bookworm)linux 6.1.129-1 (bookworm)
debianlinux-6.1< linux 6.1.129-1 (bookworm)linux 6.1.129-1 (bookworm)
linuxlinux
linuxlinux>= e3876605450979fe52a1a03e7eb78a89bf59e76a < d0e0f9c8218826926d7692980c98236d9f21fd3cd0e0f9c8218826926d7692980c98236d9f21fd3c
linuxlinux>= e3876605450979fe52a1a03e7eb78a89bf59e76a < c337c08819a4ec49edfdcd8fc46fbee120d8a5b2c337c08819a4ec49edfdcd8fc46fbee120d8a5b2
linuxlinux>= e3876605450979fe52a1a03e7eb78a89bf59e76a < 0e2f1d93d287d544d26f8ff293ea820a8079b9f80e2f1d93d287d544d26f8ff293ea820a8079b9f8
linuxlinux>= e3876605450979fe52a1a03e7eb78a89bf59e76a < 5860abbf15eeb61838b5e32e721ba67b0aa844505860abbf15eeb61838b5e32e721ba67b0aa84450
linuxlinux>= e3876605450979fe52a1a03e7eb78a89bf59e76a < 6ce38b5a6a49e65bad163162a54cb3f104c40b486ce38b5a6a49e65bad163162a54cb3f104c40b48
linuxlinux>= e3876605450979fe52a1a03e7eb78a89bf59e76a < 33e2168788f8fb5cb8bd4f36cb1ef37d1d34dada33e2168788f8fb5cb8bd4f36cb1ef37d1d34dada
linuxlinux>= e3876605450979fe52a1a03e7eb78a89bf59e76a < 1489824e5226a26841c70639ebd2d1aed390764b1489824e5226a26841c70639ebd2d1aed390764b
linuxlinux>= e3876605450979fe52a1a03e7eb78a89bf59e76a < d1f9f79fa2af8e3b45cffdeef66e05833480148ad1f9f79fa2af8e3b45cffdeef66e05833480148a
linuxlinux_kernel
linuxlinux_kernel>= 0 < 5.10.237-15.10.237-1
linuxlinux_kernel>= 0 < 6.1.129-16.1.129-1
linuxlinux_kernel>= 0 < 6.12.13-16.12.13-1
linuxlinux_kernel>= 0 < 6.12.13-16.12.13-1
linuxlinux_kernel>= 0 < 5.4.0-216.2365.4.0-216.236
linuxlinux_kernel>= 0 < 5.15.0-140.1505.15.0-140.150
linuxlinux_kernel>= 0 < 6.8.0-64.676.8.0-64.67
linuxlinux_kernel>= 2.6.13 < 5.4.2915.4.291
linuxlinux_kernel>= 5.11 < 5.15.1795.15.179
linuxlinux_kernel>= 5.16 < 6.1.1296.1.129
linuxlinux_kernel>= 5.5 < 5.10.2355.10.235
linuxlinux_kernel>= 6.13 < 6.13.26.13.2
linuxlinux_kernel>= 6.2 < 6.6.766.6.76

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv8.8HIGH
vendor_ubuntu8.8HIGH
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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