CVE-2021-47449

unknown

Published — · Modified —

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CVSS v3

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CVSS v4 NEW

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not yet in upstream

VIR risk

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Description

In the Linux kernel, the following vulnerability has been resolved: ice: fix locking for Tx timestamp tracking flush Commit 4dd0d5c33c3e ("ice: add lock around Tx timestamp tracker flush") added a lock around the Tx timestamp tracker flow which is used to cleanup any left over SKBs and prepare for device removal. This lock is problematic because it is being held around a call to ice_clear_phy_tstamp. The clear function takes a mutex to send a PHY write command to firmware. This could lead to a deadlock if the mutex actually sleeps, and causes the following warning on a kernel with preemption debugging enabled: [ 715.419426] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:573 [ 715.427900] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 3100, name: rmmod [ 715.435652] INFO: lockdep is turned off. [ 715.439591] Preemption disabled at: [ 715.439594] [<0000000000000000>] 0x0 [ 715.446678] CPU: 52 PID: 3100 Comm: rmmod Tainted: G W OE 5.15.0-rc4+ #42 bdd7ec3018e725f159ca0d372ce8c2c0e784891c [ 715.458058] Hardware name: Intel Corporation S2600STQ/S2600STQ, BIOS SE5C620.86B.02.01.0010.010620200716 01/06/2020 [ 715.468483] Call Trace: [ 715.470940] dump_stack_lvl+0x6a/0x9a [ 715.474613] ___might_sleep.cold+0x224/0x26a [ 715.478895] __mutex_lock+0xb3/0x1440 [ 715.482569] ? stack_depot_save+0x378/0x500 [ 715.486763] ? ice_sq_send_cmd+0x78/0x14c0 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d] [ 715.494979] ? kfree+0xc1/0x520 [ 715.498128] ? mutex_lock_io_nested+0x12a0/0x12a0 [ 715.502837] ? kasan_set_free_info+0x20/0x30 [ 715.507110] ? __kasan_slab_free+0x10b/0x140 [ 715.511385] ? slab_free_freelist_hook+0xc7/0x220 [ 715.516092] ? kfree+0xc1/0x520 [ 715.519235] ? ice_deinit_lag+0x16c/0x220 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d] [ 715.527359] ? ice_remove+0x1cf/0x6a0 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d] [ 715.535133] ? pci_device_remove+0xab/0x1d0 [ 715.539318] ? __device_release_driver+0x35b/0x690 [ 715.544110] ? driver_detach+0x214/0x2f0 [ 715.548035] ? bus_remove_driver+0x11d/0x2f0 [ 715.552309] ? pci_unregister_driver+0x26/0x250 [ 715.556840] ? ice_module_exit+0xc/0x2f [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d] [ 715.564799] ? __do_sys_delete_module.constprop.0+0x2d8/0x4e0 [ 715.570554] ? do_syscall_64+0x3b/0x90 [ 715.574303] ? entry_SYSCALL_64_after_hwframe+0x44/0xae [ 715.579529] ? start_flush_work+0x542/0x8f0 [ 715.583719] ? ice_sq_send_cmd+0x78/0x14c0 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d] [ 715.591923] ice_sq_send_cmd+0x78/0x14c0 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d] [ 715.599960] ? wait_for_completion_io+0x250/0x250 [ 715.604662] ? lock_acquire+0x196/0x200 [ 715.608504] ? do_raw_spin_trylock+0xa5/0x160 [ 715.612864] ice_sbq_rw_reg+0x1e6/0x2f0 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d] [ 715.620813] ? ice_reset+0x130/0x130 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d] [ 715.628497] ? __debug_check_no_obj_freed+0x1e8/0x3c0 [ 715.633550] ? trace_hardirqs_on+0x1c/0x130 [ 715.637748] ice_write_phy_reg_e810+0x70/0xf0 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d] [ 715.646220] ? do_raw_spin_trylock+0xa5/0x160 [ 715.650581] ? ice_ptp_release+0x910/0x910 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d] [ 715.658797] ? ice_ptp_release+0x255/0x910 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d] [ 715.667013] ice_clear_phy_tstamp+0x2c/0x110 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d] [ 715.675403] ice_ptp_release+0x408/0x910 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d] [ 715.683440] ice_remove+0x560/0x6a0 [ice 9a7e1ec00971c89ecd3fe0d4dc7da2b3786a421d] [ 715.691037] ? _raw_spin_unlock_irqrestore+0x46/0x73 [ 715.696005] pci_device_remove+0xab/0x1d0 [ 715.700018] __device_release_driver+0x35b/0x690 [ 715.704637] driver_detach+0x214/0x2f0 [ 715.708389] bus_remove_driver+0x11d/0x2f0 [ 715.712489] pci_unregister_driver+0x26/0x250 [ 71 ---truncated---

Predictions

Exploit likelihood

20%

Patch ETA

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Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

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OS impact

OS	Version	Status	Fixed in
sles		affected
debian	bookworm	fixed	`5.14.16-1`
debian	bullseye	fixed	`0`
debian	forky	fixed	`5.14.16-1`
debian	sid	fixed	`5.14.16-1`
debian	trixie	fixed	`5.14.16-1`

References

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.