{"id":"CVE-2022-49096","state":"PUBLISHED","title":"net: sfc: add missing xdp queue reinitialization","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: sfc: add missing xdp queue reinitialization\n\nAfter rx/tx ring buffer size is changed, kernel panic occurs when\nit acts XDP_TX or XDP_REDIRECT.\n\nWhen tx/rx ring buffer size is changed(ethtool -G), sfc driver\nreallocates and reinitializes rx and tx queues and their buffer\n(tx_queue->buffer).\nBut it misses reinitializing xdp queues(efx->xdp_tx_queues).\nSo, while it is acting XDP_TX or XDP_REDIRECT, it uses the uninitialized\ntx_queue->buffer.\n\nA new function efx_set_xdp_channels() is separated from efx_set_channels()\nto handle only xdp queues.\n\nSplat looks like:\n   BUG: kernel NULL pointer dereference, address: 000000000000002a\n   #PF: supervisor write access in kernel mode\n   #PF: error_code(0x0002) - not-present page\n   PGD 0 P4D 0\n   Oops: 0002 [#4] PREEMPT SMP NOPTI\n   RIP: 0010:efx_tx_map_chunk+0x54/0x90 [sfc]\n   CPU: 2 PID: 0 Comm: swapper/2 Tainted: G      D           5.17.0+ #55 e8beeee8289528f11357029357cf\n   Code: 48 8b 8d a8 01 00 00 48 8d 14 52 4c 8d 2c d0 44 89 e0 48 85 c9 74 0e 44 89 e2 4c 89 f6 48 80\n   RSP: 0018:ffff92f121e45c60 EFLAGS: 00010297\n   RIP: 0010:efx_tx_map_chunk+0x54/0x90 [sfc]\n   RAX: 0000000000000040 RBX: ffff92ea506895c0 RCX: ffffffffc0330870\n   RDX: 0000000000000001 RSI: 00000001139b10ce RDI: ffff92ea506895c0\n   RBP: ffffffffc0358a80 R08: 00000001139b110d R09: 0000000000000000\n   R10: 0000000000000001 R11: ffff92ea414c0088 R12: 0000000000000040\n   R13: 0000000000000018 R14: 00000001139b10ce R15: ffff92ea506895c0\n   FS:  0000000000000000(0000) GS:ffff92f121ec0000(0000) knlGS:0000000000000000\n   CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n   Code: 48 8b 8d a8 01 00 00 48 8d 14 52 4c 8d 2c d0 44 89 e0 48 85 c9 74 0e 44 89 e2 4c 89 f6 48 80\n   CR2: 000000000000002a CR3: 00000003e6810004 CR4: 00000000007706e0\n   RSP: 0018:ffff92f121e85c60 EFLAGS: 00010297\n   PKRU: 55555554\n   RAX: 0000000000000040 RBX: ffff92ea50689700 RCX: ffffffffc0330870\n   RDX: 0000000000000001 RSI: 00000001145a90ce RDI: ffff92ea50689700\n   RBP: ffffffffc0358a80 R08: 00000001145a910d R09: 0000000000000000\n   R10: 0000000000000001 R11: ffff92ea414c0088 R12: 0000000000000040\n   R13: 0000000000000018 R14: 00000001145a90ce R15: ffff92ea50689700\n   FS:  0000000000000000(0000) GS:ffff92f121e80000(0000) knlGS:0000000000000000\n   CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n   CR2: 000000000000002a CR3: 00000003e6810005 CR4: 00000000007706e0\n   PKRU: 55555554\n   Call Trace:\n    <IRQ>\n    efx_xdp_tx_buffers+0x12b/0x3d0 [sfc 84c94b8e32d44d296c17e10a634d3ad454de4ba5]\n    __efx_rx_packet+0x5c3/0x930 [sfc 84c94b8e32d44d296c17e10a634d3ad454de4ba5]\n    efx_rx_packet+0x28c/0x2e0 [sfc 84c94b8e32d44d296c17e10a634d3ad454de4ba5]\n    efx_ef10_ev_process+0x5f8/0xf40 [sfc 84c94b8e32d44d296c17e10a634d3ad454de4ba5]\n    ? enqueue_task_fair+0x95/0x550\n    efx_poll+0xc4/0x360 [sfc 84c94b8e32d44d296c17e10a634d3ad454de4ba5]","publishedAt":"2025-02-26T01:54:49.108Z","updatedAt":"2026-08-05T08:53:55.150Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"3990a8fffbdad5765f47ea593f9de66c91762059","status":"affected","lessThan":"ed7a824fda8732578d1014fad1f7fb0363705090","versionType":"git"},{"version":"3990a8fffbdad5765f47ea593f9de66c91762059","status":"affected","lessThan":"b8c46bc358d84701e7f7ffa054037db25f25da0e","versionType":"git"},{"version":"3990a8fffbdad5765f47ea593f9de66c91762059","status":"affected","lessThan":"dcc85e1593686e42c6749ef3d356db34759d59e8","versionType":"git"},{"version":"3990a8fffbdad5765f47ea593f9de66c91762059","status":"affected","lessThan":"059a47f1da93811d37533556d67e72f2261b1127","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/ethernet/sfc/efx_channels.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.5","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.5","versionType":"semver"},{"version":"5.15.34","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"5.16.20","status":"unaffected","lessThanOrEqual":"5.16.*","versionType":"semver"},{"version":"5.17.3","status":"unaffected","lessThanOrEqual":"5.17.*","versionType":"semver"},{"version":"5.18","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/ethernet/sfc/efx_channels.c"]}],"references":["https://git.kernel.org/stable/c/ed7a824fda8732578d1014fad1f7fb0363705090","https://git.kernel.org/stable/c/b8c46bc358d84701e7f7ffa054037db25f25da0e","https://git.kernel.org/stable/c/dcc85e1593686e42c6749ef3d356db34759d59e8","https://git.kernel.org/stable/c/059a47f1da93811d37533556d67e72f2261b1127"],"weaknesses":["CWE-476"],"ingestedAt":"2026-10-29T20:05:26.763Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2022/49xxx/CVE-2022-49096.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2022-49096","state":"PUBLISHED","datePublished":"2025-02-26T01:54:49.108Z","dateUpdated":"2026-08-05T08:53:55.150Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2025-02-26T01:49:39.249Z"},"containers":{"cna":{"title":"net: sfc: add missing xdp queue reinitialization","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: sfc: add missing xdp queue reinitialization\n\nAfter rx/tx ring buffer size is changed, kernel panic occurs when\nit acts XDP_TX or XDP_REDIRECT.\n\nWhen tx/rx ring buffer size is changed(ethtool -G), sfc driver\nreallocates and reinitializes rx and tx queues and their buffer\n(tx_queue->buffer).\nBut it misses reinitializing xdp queues(efx->xdp_tx_queues).\nSo, while it is acting XDP_TX or XDP_REDIRECT, it uses the uninitialized\ntx_queue->buffer.\n\nA new function efx_set_xdp_channels() is separated from efx_set_channels()\nto handle only xdp queues.\n\nSplat looks like:\n   BUG: kernel NULL pointer dereference, address: 000000000000002a\n   #PF: supervisor write access in kernel mode\n   #PF: error_code(0x0002) - not-present page\n   PGD 0 P4D 0\n   Oops: 0002 [#4] PREEMPT SMP NOPTI\n   RIP: 0010:efx_tx_map_chunk+0x54/0x90 [sfc]\n   CPU: 2 PID: 0 Comm: swapper/2 Tainted: G      D           5.17.0+ #55 e8beeee8289528f11357029357cf\n   Code: 48 8b 8d a8 01 00 00 48 8d 14 52 4c 8d 2c d0 44 89 e0 48 85 c9 74 0e 44 89 e2 4c 89 f6 48 80\n   RSP: 0018:ffff92f121e45c60 EFLAGS: 00010297\n   RIP: 0010:efx_tx_map_chunk+0x54/0x90 [sfc]\n   RAX: 0000000000000040 RBX: ffff92ea506895c0 RCX: ffffffffc0330870\n   RDX: 0000000000000001 RSI: 00000001139b10ce RDI: ffff92ea506895c0\n   RBP: ffffffffc0358a80 R08: 00000001139b110d R09: 0000000000000000\n   R10: 0000000000000001 R11: ffff92ea414c0088 R12: 0000000000000040\n   R13: 0000000000000018 R14: 00000001139b10ce R15: ffff92ea506895c0\n   FS:  0000000000000000(0000) GS:ffff92f121ec0000(0000) knlGS:0000000000000000\n   CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n   Code: 48 8b 8d a8 01 00 00 48 8d 14 52 4c 8d 2c d0 44 89 e0 48 85 c9 74 0e 44 89 e2 4c 89 f6 48 80\n   CR2: 000000000000002a CR3: 00000003e6810004 CR4: 00000000007706e0\n   RSP: 0018:ffff92f121e85c60 EFLAGS: 00010297\n   PKRU: 55555554\n   RAX: 0000000000000040 RBX: ffff92ea50689700 RCX: ffffffffc0330870\n   RDX: 0000000000000001 RSI: 00000001145a90ce RDI: ffff92ea50689700\n   RBP: ffffffffc0358a80 R08: 00000001145a910d R09: 0000000000000000\n   R10: 0000000000000001 R11: ffff92ea414c0088 R12: 0000000000000040\n   R13: 0000000000000018 R14: 00000001145a90ce R15: ffff92ea50689700\n   FS:  0000000000000000(0000) GS:ffff92f121e80000(0000) knlGS:0000000000000000\n   CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n   CR2: 000000000000002a CR3: 00000003e6810005 CR4: 00000000007706e0\n   PKRU: 55555554\n   Call Trace:\n    <IRQ>\n    efx_xdp_tx_buffers+0x12b/0x3d0 [sfc 84c94b8e32d44d296c17e10a634d3ad454de4ba5]\n    __efx_rx_packet+0x5c3/0x930 [sfc 84c94b8e32d44d296c17e10a634d3ad454de4ba5]\n    efx_rx_packet+0x28c/0x2e0 [sfc 84c94b8e32d44d296c17e10a634d3ad454de4ba5]\n    efx_ef10_ev_process+0x5f8/0xf40 [sfc 84c94b8e32d44d296c17e10a634d3ad454de4ba5]\n    ? enqueue_task_fair+0x95/0x550\n    efx_poll+0xc4/0x360 [sfc 84c94b8e32d44d296c17e10a634d3ad454de4ba5]"}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"3990a8fffbdad5765f47ea593f9de66c91762059","status":"affected","lessThan":"ed7a824fda8732578d1014fad1f7fb0363705090","versionType":"git"},{"version":"3990a8fffbdad5765f47ea593f9de66c91762059","status":"affected","lessThan":"b8c46bc358d84701e7f7ffa054037db25f25da0e","versionType":"git"},{"version":"3990a8fffbdad5765f47ea593f9de66c91762059","status":"affected","lessThan":"dcc85e1593686e42c6749ef3d356db34759d59e8","versionType":"git"},{"version":"3990a8fffbdad5765f47ea593f9de66c91762059","status":"affected","lessThan":"059a47f1da93811d37533556d67e72f2261b1127","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/ethernet/sfc/efx_channels.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.5","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.5","versionType":"semver"},{"version":"5.15.34","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"5.16.20","status":"unaffected","lessThanOrEqual":"5.16.*","versionType":"semver"},{"version":"5.17.3","status":"unaffected","lessThanOrEqual":"5.17.*","versionType":"semver"},{"version":"5.18","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/net/ethernet/sfc/efx_channels.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/ed7a824fda8732578d1014fad1f7fb0363705090"},{"url":"https://git.kernel.org/stable/c/b8c46bc358d84701e7f7ffa054037db25f25da0e"},{"url":"https://git.kernel.org/stable/c/dcc85e1593686e42c6749ef3d356db34759d59e8"},{"url":"https://git.kernel.org/stable/c/059a47f1da93811d37533556d67e72f2261b1127"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The vulnerable state is created only via local ethtool ring-parameter changes (ETHTOOL_SRINGPARAM / ETHTOOL_MSG_RINGS_SET → efx_realloc_channels). Remote packets merely exercise the already-dangling XDP TX queue pointers after that local reconfiguration.\nAC:L - A local attacker who can change ring parameters (and who can rely on or attach an XDP program that returns XDP_TX/XDP_REDIRECT) can reliably provoke the stale xdp_tx_queues use; this is a deterministic post-realloc UAF, not a race or otherwise attacker-uncontrollable condition.\nPR:L - Triggering the realloc path requires CAP_NET_ADMIN in the network namespace that owns the Solarflare device (ns_capable), which is available to low-privileged contexts such as containers granted CAP_NET_ADMIN, so Privileges Required is Low rather than High.\nUI:N - No separate victim action is required; the attacker (or automated privileged tooling they control) performs the ethtool reconfiguration and can generate or wait for traffic that hits XDP_TX/XDP_REDIRECT.\nS:U - Impact stays within the kernel/host security authority; this is a same-host driver memory-corruption/DoS issue, not a VM escape, IOMMU bypass, or other cross-boundary break.\nC:H - efx->xdp_tx_queues retains pointers into kfree'd channel/tx_queue objects, so the subsequent XDP TX path is a use-after-free that can be leveraged for arbitrary kernel memory disclosure via controlled reuse of the freed objects.\nI:H - The same UAF lets an attacker spray/reuse the freed tx_queue/channel memory and corrupt kernel state through efx_tx_map_chunk and related TX bookkeeping, enabling integrity compromise and control-flow hijacking primitives.\nA:H - The demonstrated failure is a kernel NULL-pointer dereference/oops in IRQ/NAPI context (efx_tx_map_chunk), and UAFs of this form also crash unpredictably when freed memory is reused, so availability impact is High."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T08:53:55.150Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"5.15.34"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"5.16.20"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"5.17.3"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"5.18"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":5.5,"attackVector":"LOCAL","baseSeverity":"MEDIUM","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","integrityImpact":"NONE","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"HIGH","privilegesRequired":"LOW","confidentialityImpact":"NONE"}},{"other":{"type":"ssvc","content":{"id":"CVE-2022-49096","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2025-10-01T19:49:29.340028Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-476","lang":"en","type":"CWE","description":"CWE-476 NULL Pointer Dereference"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2025-10-01T19:57:05.717Z"}}]}}}