CVE-2024-46678 bonding: change ipsec_lock from spin lock to mutex
A locking bug in the Linux kernel bonding driver causes a system crash when changing the active slave on a bond with IPsec enabled.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2024-46678?
CVE-2024-46678 is a high-severity denial of service vulnerability in Linux kernel, published on 13 Sep 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
bonding: change ipsec_lock from spin lock to mutex
In the cited commit, bond->ipsec_lock is added to protect ipsec_list, hence xdo_dev_state_add and xdo_dev_state_delete are called inside this lock. As ipsec_lock is a spin lock and such xfrmdev ops may sleep, "scheduling while atomic" will be triggered when changing bond's active slave.
[ 101.055189] BUG: scheduling while atomic: bash/902/0x00000200 [ 101.055726] Modules linked in: [ 101.058211] CPU: 3 PID: 902 Comm: bash Not tainted 6.9.0-rc4+ #1 [ 101.058760] Hardware name: [ 101.059434] Call Trace: [ 101.059436] <TASK> [ 101.060873] dump_stack_lvl+0x51/0x60 [ 101.061275] __schedule_bug+0x4e/0x60 [ 101.061682] __schedule+0x612/0x7c0 [ 101.062078] ? __mod_timer+0x25c/0x370 [ 101.062486] schedule+0x25/0xd0 [ 101.062845] schedule_timeout+0x77/0xf0 [ 101.063265] ? asm_common_interrupt+0x22/0x40 [ 101.063724] ? __bpf_trace_itimer_state+0x10/0x10 [ 101.064215] __wait_for_common+0x87/0x190 [ 101.064648] ? usleep_range_state+0x90/0x90 [ 101.065091] cmd_exec+0x437/0xb20 [mlx5_core] [ 101.065569] mlx5_cmd_do+0x1e/0x40 [mlx5_core] [ 101.066051] mlx5_cmd_exec+0x18/0x30 [mlx5_core] [ 101.066552] mlx5_crypto_create_dek_key+0xea/0x120 [mlx5_core] [ 101.067163] ? bonding_sysfs_store_option+0x4d/0x80 [bonding] [ 101.067738] ? kmalloc_trace+0x4d/0x350 [ 101.068156] mlx5_ipsec_create_sa_ctx+0x33/0x100 [mlx5_core] [ 101.068747] mlx5e_xfrm_add_state+0x47b/0xaa0 [mlx5_core] [ 101.069312] bond_change_active_slave+0x392/0x900 [bonding] [ 101.069868] bond_option_active_slave_set+0x1c2/0x240 [bonding] [ 101.070454] __bond_opt_set+0xa6/0x430 [bonding] [ 101.070935] __bond_opt_set_notify+0x2f/0x90 [bonding] [ 101.071453] bond_opt_tryset_rtnl+0x72/0xb0 [bonding] [ 101.071965] bonding_sysfs_store_option+0x4d/0x80 [bonding] [ 101.072567] kernfs_fop_write_iter+0x10c/0x1a0 [ 101.073033] vfs_write+0x2d8/0x400 [ 101.073416] ? alloc_fd+0x48/0x180 [ 101.073798] ksys_write+0x5f/0xe0 [ 101.074175] do_syscall_64+0x52/0x110 [ 101.074576] entry_SYSCALL_64_after_hwframe+0x4b/0x53
As bond_ipsec_add_sa_all and bond_ipsec_del_sa_all are only called from bond_change_active_slave, which requires holding the RTNL lock. And bond_ipsec_add_sa and bond_ipsec_del_sa are xfrm state xdo_dev_state_add and xdo_dev_state_delete APIs, which are in user context. So ipsec_lock doesn't have to be spin lock, change it to mutex, and thus the above issue can be resolved.
Weakness: CWE-667
Which versions are affected by CVE-2024-46678?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2024-46678?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2024-46678 being exploited?
There is no known exploitation of CVE-2024-46678 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-49590, BELL-CVE-2024-46678, DEBIAN-CVE-2024-46678, GHSA-2mh2-9xm5-m59q, ROOT-OS-DEBIAN-11-CVE-2024-46678, ROOT-OS-DEBIAN-12-CVE-2024-46678 and 2 more.