Bug 2401483 (CVE-2022-50498)

Summary: CVE-2022-50498 kernel: eth: alx: take rtnl_lock on resume
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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Doc Text:
A missing synchronization flaw was found in the Linux kernel's Atheros alx Ethernet driver in the suspend/resume path. A local user can trigger this issue during system suspend/resume operations when the driver fails to acquire the rtnl_lock mutex before calling internal network device open functions. This causes an RTNL assertion failure, resulting in a kernel warning or potential race conditions during device state transitions.
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Description OSIDB Bzimport 2025-10-04 16:03:06 UTC 
In the Linux kernel, the following vulnerability has been resolved:

eth: alx: take rtnl_lock on resume

Zbynek reports that alx trips an rtnl assertion on resume:

 RTNL: assertion failed at net/core/dev.c (2891)
 RIP: 0010:netif_set_real_num_tx_queues+0x1ac/0x1c0
 Call Trace:
  <TASK>
  __alx_open+0x230/0x570 [alx]
  alx_resume+0x54/0x80 [alx]
  ? pci_legacy_resume+0x80/0x80
  dpm_run_callback+0x4a/0x150
  device_resume+0x8b/0x190
  async_resume+0x19/0x30
  async_run_entry_fn+0x30/0x130
  process_one_work+0x1e5/0x3b0

indeed the driver does not hold rtnl_lock during its internal close
and re-open functions during suspend/resume. Note that this is not
a huge bug as the driver implements its own locking, and does not
implement changing the number of queues, but we need to silence
the splat.
Comment 1 Alexander B 2025-10-06 16:14:00 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2025100419-CVE-2022-50498-c9ab@gregkh/T