CVEvulnerability
CVE-2024-49980
5.5 MEDIUM
Official page ↗
- Status
- Analyzed
- Published
- 2024-10-21
- Last modified
- 2026-06-17
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- CVSS 3.1 ([email protected])
- 5.5 MEDIUM — CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Weaknesses
- CWE-667
Description
In the Linux kernel, the following vulnerability has been resolved:
vrf: revert "vrf: Remove unnecessary RCU-bh critical section"
This reverts commit 504fc6f4f7f681d2a03aa5f68aad549d90eab853.
dev_queue_xmit_nit is expected to be called with BH disabled.
__dev_queue_xmit has the following:
/* Disable soft irqs for various locks below. Also
* stops preemption for RCU.
*/
rcu_read_lock_bh();
VRF must follow this invariant. The referenced commit removed this
protection. Which triggered a lockdep warning:
================================
WARNING: inconsistent lock state
6.11.0 #1 Tainted: G W
--------------------------------
inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage.
btserver/134819 [HC0[0]:SC0[0]:HE1:SE1] takes:
ffff8882da30c118 (rlock-AF_PACKET){+.?.}-{2:2}, at: tpacket_rcv+0x863/0x3b30
{IN-SOFTIRQ-W} state was registered at:
lock_acquire+0x19a/0x4f0
_raw_spin_lock+0x27/0x40
packet_rcv+0xa33/0x1320
__netif_receive_skb_core.constprop.0+0xcb0/0x3a90
__netif_receive_skb_list_core+0x2c9/0x890
netif_receive_skb_list_internal+0x610/0xcc0
[...]
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(rlock-AF_PACKET);
<Interrupt>
lock(rlock-AF_PACKET);
*** DEADLOCK ***
Call Trace:
<TASK>
dump_stack_lvl+0x73/0xa0
mark_lock+0x102e/0x16b0
__lock_acquire+0x9ae/0x6170
lock_acquire+0x19a/0x4f0
_raw_spin_lock+0x27/0x40
tpacket_rcv+0x863/0x3b30
dev_queue_xmit_nit+0x709/0xa40
vrf_finish_direct+0x26e/0x340 [vrf]
vrf_l3_out+0x5f4/0xe80 [vrf]
__ip_local_out+0x51e/0x7a0
[...]
Affected configurations
• linux linux kernel (>= 6.6 < 6.6.55)
• linux linux kernel (>= 6.7 < 6.10.14)
• linux linux kernel (>= 6.11 < 6.11.3)
• linux linux kernel 6.12
Related
Weakness · CWE (1)
- CWE-667 Improper Locking weakness
References
- https://git.kernel.org/stable/c/718a752bd746b3f4dd62516bb437baf73d548415 Patch
- https://git.kernel.org/stable/c/8c9381b3138246d46536db93ed696832abd70204 Patch
- https://git.kernel.org/stable/c/b04c4d9eb4f25b950b33218e33b04c94e7445e51 Patch
- https://git.kernel.org/stable/c/e61f8c4d179b2ffc0d3b7f821c3734be738643d0 Patch