RDMA/mlx5: Fix UMR hang in LAG error state unload
Summary
| CVE | CVE-2026-45973 |
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-05-27 14:17:14 UTC |
| Updated | 2026-05-27 14:48:03 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved:
RDMA/mlx5: Fix UMR hang in LAG error state unload
During firmware reset in LAG mode, a race condition causes the driver
to hang indefinitely while waiting for UMR completion during device
unload. See [1].
In LAG mode the bond device is only registered on the master, so it
never sees sys_error events from the slave.
During firmware reset this causes UMR waits to hang forever on unload
as the slave is dead but the master hasn't entered error state yet, so
UMR posts succeed but completions never arrive.
Fix this by adding a sys_error notifier that gets registered before
MLX5_IB_STAGE_IB_REG and stays alive until after ib_unregister_device().
This ensures error events reach the bond device throughout teardown.
[1]
Call Trace:
__schedule+0x2bd/0x760
schedule+0x37/0xa0
schedule_preempt_disabled+0xa/0x10
__mutex_lock.isra.6+0x2b5/0x4a0
__mlx5_ib_dereg_mr+0x606/0x870 [mlx5_ib]
? __xa_erase+0x4a/0xa0
? _cond_resched+0x15/0x30
? wait_for_completion+0x31/0x100
ib_dereg_mr_user+0x48/0xc0 [ib_core]
? rdmacg_uncharge_hierarchy+0xa0/0x100
destroy_hw_idr_uobject+0x20/0x50 [ib_uverbs]
uverbs_destroy_uobject+0x37/0x150 [ib_uverbs]
__uverbs_cleanup_ufile+0xda/0x140 [ib_uverbs]
uverbs_destroy_ufile_hw+0x3a/0xf0 [ib_uverbs]
ib_uverbs_remove_one+0xc3/0x140 [ib_uverbs]
remove_client_context+0x8b/0xd0 [ib_core]
disable_device+0x8c/0x130 [ib_core]
__ib_unregister_device+0x10d/0x180 [ib_core]
ib_unregister_device+0x21/0x30 [ib_core]
__mlx5_ib_remove+0x1e4/0x1f0 [mlx5_ib]
auxiliary_bus_remove+0x1e/0x30
device_release_driver_internal+0x103/0x1f0
bus_remove_device+0xf7/0x170
device_del+0x181/0x410
mlx5_rescan_drivers_locked.part.10+0xa9/0x1d0 [mlx5_core]
mlx5_disable_lag+0x253/0x260 [mlx5_core]
mlx5_lag_disable_change+0x89/0xc0 [mlx5_core]
mlx5_eswitch_disable+0x67/0xa0 [mlx5_core]
mlx5_unload+0x15/0xd0 [mlx5_core]
mlx5_unload_one+0x71/0xc0 [mlx5_core]
mlx5_sync_reset_reload_work+0x83/0x100 [mlx5_core]
process_one_work+0x1a7/0x360
worker_thread+0x30/0x390
? create_worker+0x1a0/0x1a0
kthread+0x116/0x130
? kthread_flush_work_fn+0x10/0x10
ret_from_fork+0x22/0x40 |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|
| CNA |
Linux |
Linux |
affected 6b0acf6a94c31efa43fce4edc22413a3390f9c05 c8fb5c965ac7d0104872a8e4f6451f3bc6328199 git |
Not specified |
| CNA |
Linux |
Linux |
affected ede132a5cf559f3ab35a4c28bac4f4a6c20334d8 6d838873da9cb97551d42316967cc82bf8f8031b git |
Not specified |
| CNA |
Linux |
Linux |
affected ede132a5cf559f3ab35a4c28bac4f4a6c20334d8 613f5d4139b6ba801ccd93f9a28943be60d903bc git |
Not specified |
| CNA |
Linux |
Linux |
affected ede132a5cf559f3ab35a4c28bac4f4a6c20334d8 ebc2164a4cd4314503f1a0c8e7aaf76d7e5fa211 git |
Not specified |
| CNA |
Linux |
Linux |
affected 921fcf2971a1e8d3b904ba2c2905b96f4ec3d4ad git |
Not specified |
| CNA |
Linux |
Linux |
affected 542bd62b7a7f37182c9ef192c2bd25d118c144e4 git |
Not specified |
| CNA |
Linux |
Linux |
affected 6.12.2 6.12.75 semver |
Not specified |
| CNA |
Linux |
Linux |
affected 6.6.64 6.7 semver |
Not specified |
| CNA |
Linux |
Linux |
affected 6.11.11 6.12 semver |
Not specified |
| CNA |
Linux |
Linux |
affected 6.13 |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.13 semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.12.75 6.12.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.18.14 6.18.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.19.4 6.19.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 7.0 * original_commit_for_fix |
Not specified |
References
| Reference | Source | Link | Tags |
|---|
| git.kernel.org/stable/c/ebc2164a4cd4314503f1a0c8e7aaf76d7e5fa211 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/613f5d4139b6ba801ccd93f9a28943be60d903bc |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/c8fb5c965ac7d0104872a8e4f6451f3bc6328199 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/6d838873da9cb97551d42316967cc82bf8f8031b |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| CVE Program record |
CVE.ORG |
www.cve.org |
canonical |
| NVD vulnerability detail |
NVD |
nvd.nist.gov |
canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.