Bug 2266597 (CVE-2021-47019)

Summary: CVE-2021-47019 kernel: mt76: possible invalid register access
Product: [Other] Security Response Reporter: Rohit Keshri <rkeshri>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: acaringi, allarkin, aquini, bhu, chwhite, cye, cyin, dbohanno, debarbos, dfreiber, drow, dvlasenk, esandeen, ezulian, hkrzesin, jarod, jburrell, jdenham, jfaracco, jforbes, jlelli, joe.lawrence, jshortt, jstancek, jwyatt, kcarcia, ldoskova, lgoncalv, lzampier, mcascell, mleitner, mmilgram, mstowell, nmurray, ptalbert, rparrazo, rrobaina, rvrbovsk, rysulliv, scweaver, sidakwo, sukulkar, tglozar, tyberry, vkumar, wcosta, williams, wmealing, ycote, ykopkova, zhijwang
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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Doc Text:
A flaw was found in the mt76 wireless driver (mt7921) in the Linux kernel. This flaw allows a local attacker to trigger a denial of service during system suspend. When the system enters suspend mode, an interrupt handler may still access invalid device registers if the PCIe controller is already suspended. This leads to a kernel panic and system crash, affecting availability.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 2266598    
Bug Blocks: 2266587    

Description Rohit Keshri 2024-02-28 12:46:54 UTC 
In the Linux kernel, the following vulnerability has been resolved:

mt76: mt7921: fix possible invalid register access

Disable the interrupt and synchronze for the pending irq handlers to ensure
the irq tasklet is not being scheduled after the suspend to avoid the
possible invalid register access acts when the host pcie controller is
suspended.

[17932.910534] mt7921e 0000:01:00.0: pci_pm_suspend+0x0/0x22c returned 0 after 21375 usecs
[17932.910590] pcieport 0000:00:00.0: calling pci_pm_suspend+0x0/0x22c @ 18565, parent: pci0000:00
[17932.910602] pcieport 0000:00:00.0: pci_pm_suspend+0x0/0x22c returned 0 after 8 usecs
[17932.910671] mtk-pcie 11230000.pcie: calling platform_pm_suspend+0x0/0x60 @ 22783, parent: soc
[17932.910674] mtk-pcie 11230000.pcie: platform_pm_suspend+0x0/0x60 returned 0 after 0 usecs

...

17933.615352] x1 : 00000000000d4200 x0 : ffffff8269ca2300
[17933.620666] Call trace:
[17933.623127]  mt76_mmio_rr+0x28/0xf0 [mt76]
[17933.627234]  mt7921_rr+0x38/0x44 [mt7921e]
[17933.631339]  mt7921_irq_tasklet+0x54/0x1d8 [mt7921e]
[17933.636309]  tasklet_action_common+0x12c/0x16c
[17933.640754]  tasklet_action+0x24/0x2c
[17933.644418]  __do_softirq+0x16c/0x344
[17933.648082]  irq_exit+0xa8/0xac
[17933.651224]  scheduler_ipi+0xd4/0x148
[17933.654890]  handle_IPI+0x164/0x2d4
[17933.658379]  gic_handle_irq+0x140/0x178
[17933.662216]  el1_irq+0xb8/0x180
[17933.665361]  cpuidle_enter_state+0xf8/0x204
[17933.669544]  cpuidle_enter+0x38/0x4c
[17933.673122]  do_idle+0x1a4/0x2a8
[17933.676352]  cpu_startup_entry+0x24/0x28
[17933.680276]  rest_init+0xd4/0xe0
[17933.683508]  arch_call_rest_init+0x10/0x18
[17933.687606]  start_kernel+0x340/0x3b4
[17933.691279] Code: aa0003f5 d503201f f953eaa8 8b344108 (b9400113)
[17933.697373] ---[ end trace a24b8e26ffbda3c5 ]---
[17933.767846] Kernel panic - not syncing: Fatal exception in interrupt

https://git.kernel.org/stable/c/b13cbc536990ff609afa878b6211cd6f6265ba60
https://git.kernel.org/stable/c/fe3fccde8870764ba3e60610774bd7bc9f8faeff
Comment 1 Rohit Keshri 2024-02-28 12:49:49 UTC 
Created kernel tracking bugs for this issue:

Affects: fedora-all [bug 2266598]
Comment 3 Justin M. Forbes 2024-02-28 18:48:57 UTC 
This was fixed for Fedora with the 5.12.4 stable kernel update.