{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2022-49201", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2022-49201", "idYear": 2022, "status": "PUBLISHED", "publishedAt": "2025-02-26T01:55:43.263Z", "updatedAt": "2026-08-05T08:54:22.016Z", "importedAt": "2026-10-24T01:56:49.724Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "ibmvnic: fix race between xmit and reset", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nibmvnic: fix race between xmit and reset\n\nThere is a race between reset and the transmit paths that can lead to\nibmvnic_xmit() accessing an scrq after it has been freed in the reset\npath. It can result in a crash like:\n\n\tKernel attempted to read user page (0) - exploit attempt? (uid: 0)\n\tBUG: Kernel NULL pointer dereference on read at 0x00000000\n\tFaulting instruction address: 0xc0080000016189f8\n\tOops: Kernel access of bad area, sig: 11 [#1]\n\t...\n\tNIP [c0080000016189f8] ibmvnic_xmit+0x60/0xb60 [ibmvnic]\n\tLR [c000000000c0046c] dev_hard_start_xmit+0x11c/0x280\n\tCall Trace:\n\t[c008000001618f08] ibmvnic_xmit+0x570/0xb60 [ibmvnic] (unreliable)\n\t[c000000000c0046c] dev_hard_start_xmit+0x11c/0x280\n\t[c000000000c9cfcc] sch_direct_xmit+0xec/0x330\n\t[c000000000bfe640] __dev_xmit_skb+0x3a0/0x9d0\n\t[c000000000c00ad4] __dev_queue_xmit+0x394/0x730\n\t[c008000002db813c] __bond_start_xmit+0x254/0x450 [bonding]\n\t[c008000002db8378] bond_start_xmit+0x40/0xc0 [bonding]\n\t[c000000000c0046c] dev_hard_start_xmit+0x11c/0x280\n\t[c000000000c00ca4] __dev_queue_xmit+0x564/0x730\n\t[c000000000cf97e0] neigh_hh_output+0xd0/0x180\n\t[c000000000cfa69c] ip_finish_output2+0x31c/0x5c0\n\t[c000000000cfd244] __ip_queue_xmit+0x194/0x4f0\n\t[c000000000d2a3c4] __tcp_transmit_skb+0x434/0x9b0\n\t[c000000000d2d1e0] __tcp_retransmit_skb+0x1d0/0x6a0\n\t[c000000000d2d984] tcp_retransmit_skb+0x34/0x130\n\t[c000000000d310e8] tcp_retransmit_timer+0x388/0x6d0\n\t[c000000000d315ec] tcp_write_timer_handler+0x1bc/0x330\n\t[c000000000d317bc] tcp_write_timer+0x5c/0x200\n\t[c000000000243270] call_timer_fn+0x50/0x1c0\n\t[c000000000243704] __run_timers.part.0+0x324/0x460\n\t[c000000000243894] run_timer_softirq+0x54/0xa0\n\t[c000000000ea713c] __do_softirq+0x15c/0x3e0\n\t[c000000000166258] __irq_exit_rcu+0x158/0x190\n\t[c000000000166420] irq_exit+0x20/0x40\n\t[c00000000002853c] timer_interrupt+0x14c/0x2b0\n\t[c000000000009a00] decrementer_common_virt+0x210/0x220\n\t--- interrupt: 900 at plpar_hcall_norets_notrace+0x18/0x2c\n\nThe immediate cause of the crash is the access of tx_scrq in the following\nsnippet during a reset, where the tx_scrq can be either NULL or an address\nthat will soon be invalid:\n\n\tibmvnic_xmit()\n\t{\n\t\t...\n\t\ttx_scrq = adapter->tx_scrq[queue_num];\n\t\ttxq = netdev_get_tx_queue(netdev, queue_num);\n\t\tind_bufp = &tx_scrq->ind_buf;\n\n\t\tif (test_bit(0, &adapter->resetting)) {\n\t\t...\n\t}\n\nBut beyond that, the call to ibmvnic_xmit() itself is not safe during a\nreset and the reset path attempts to avoid this by stopping the queue in\nibmvnic_cleanup(). However just after the queue was stopped, an in-flight\nibmvnic_complete_tx() could have restarted the queue even as the reset is\nprogressing.\n\nSince the queue was restarted we could get a call to ibmvnic_xmit() which\ncan then access the bad tx_scrq (or other fields).\n\nWe cannot however simply have ibmvnic_complete_tx() check the ->resetting\nbit and skip starting the queue. This can race at the \"back-end\" of a good\nreset which just restarted the queue but has not cleared the ->resetting\nbit yet. If we skip restarting the queue due to ->resetting being true,\nthe queue would remain stopped indefinitely potentially leading to transmit\ntimeouts.\n\nIOW ->resetting is too broad for this purpose. Instead use a new flag\nthat indicates whether or not the queues are active. Only the open/\nreset paths control when the queues are active. ibmvnic_complete_tx()\nand others wake up the queue only if the queue is marked active.\n\nSo we will have:\n\tA. reset/open thread in ibmvnic_cleanup() and __ibmvnic_open()\n\n\t\t->resetting = true\n\t\t->tx_queues_active = false\n\t\tdisable tx queues\n\t\t...\n\t\t->tx_queues_active = true\n\t\tstart tx queues\n\n\tB. Tx interrupt in ibmvnic_complete_tx():\n\n\t\tif (->tx_queues_active)\n\t\t\tnetif_wake_subqueue();\n\nTo ensure that ->tx_queues_active and state of the queues are consistent,\nwe need a lock which:\n\n\t- must also be taken in the interrupt path (ibmvnic_complete_tx())\n\t- shared across the multiple\n---truncated---", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "7ed5b31f4a6695a21f617df07646e9b15c6c1d29", "status": "affected", "versionType": "git", "lessThan": "1bd58abf595b6cf1ba6dd47ec887c4c009155fc9" }, { "version": "7ed5b31f4a6695a21f617df07646e9b15c6c1d29", "status": "affected", "versionType": "git", "lessThan": "475f9cce98b63bc145b4efa66fa51175d4cb345f" }, { "version": "7ed5b31f4a6695a21f617df07646e9b15c6c1d29", "status": "affected", "versionType": "git", "lessThan": "8507c6ade73cdbbbda5c3d31d67f52f2e1cf03fe" }, { "version": "7ed5b31f4a6695a21f617df07646e9b15c6c1d29", "status": "affected", "versionType": "git", "lessThan": "4219196d1f662cb10a462eb9e076633a3fc31a15" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "5.4", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "5.4" }, { "version": "5.15.33", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "5.16.19", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.16.*" }, { "version": "5.17.2", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.17.*" }, { "version": "5.18", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }