{"cve":"CVE-2022-49626","nvd":{"published":"2025-02-26T07:01:37.937","modified":"2026-06-17T05:18:40.050","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsfc: fix use after free when disabling sriov\n\nUse after free is detected by kfence when disabling sriov. What was read\nafter being freed was vf->pci_dev: it was freed from pci_disable_sriov\nand later read in efx_ef10_sriov_free_vf_vports, called from\nefx_ef10_sriov_free_vf_vswitching.\n\nSet the pointer to NULL at release time to not trying to read it later.\n\nReproducer and dmesg log (note that kfence doesn't detect it every time):\n$ echo 1 > /sys/class/net/enp65s0f0np0/device/sriov_numvfs\n$ echo 0 > /sys/class/net/enp65s0f0np0/device/sriov_numvfs\n\n BUG: KFENCE: use-after-free read in efx_ef10_sriov_free_vf_vswitching+0x82/0x170 [sfc]\n\n Use-after-free read at 0x00000000ff3c1ba5 (in kfence-#224):\n  efx_ef10_sriov_free_vf_vswitching+0x82/0x170 [sfc]\n  efx_ef10_pci_sriov_disable+0x38/0x70 [sfc]\n  efx_pci_sriov_configure+0x24/0x40 [sfc]\n  sriov_numvfs_store+0xfe/0x140\n  kernfs_fop_write_iter+0x11c/0x1b0\n  new_sync_write+0x11f/0x1b0\n  vfs_write+0x1eb/0x280\n  ksys_write+0x5f/0xe0\n  do_syscall_64+0x5c/0x80\n  entry_SYSCALL_64_after_hwframe+0x44/0xae\n\n kfence-#224: 0x00000000edb8ef95-0x00000000671f5ce1, size=2792, cache=kmalloc-4k\n\n allocated by task 6771 on cpu 10 at 3137.860196s:\n  pci_alloc_dev+0x21/0x60\n  pci_iov_add_virtfn+0x2a2/0x320\n  sriov_enable+0x212/0x3e0\n  efx_ef10_sriov_configure+0x67/0x80 [sfc]\n  efx_pci_sriov_configure+0x24/0x40 [sfc]\n  sriov_numvfs_store+0xba/0x140\n  kernfs_fop_write_iter+0x11c/0x1b0\n  new_sync_write+0x11f/0x1b0\n  vfs_write+0x1eb/0x280\n  ksys_write+0x5f/0xe0\n  do_syscall_64+0x5c/0x80\n  entry_SYSCALL_64_after_hwframe+0x44/0xae\n\n freed by task 6771 on cpu 12 at 3170.991309s:\n  device_release+0x34/0x90\n  kobject_cleanup+0x3a/0x130\n  pci_iov_remove_virtfn+0xd9/0x120\n  sriov_disable+0x30/0xe0\n  efx_ef10_pci_sriov_disable+0x57/0x70 [sfc]\n  efx_pci_sriov_configure+0x24/0x40 [sfc]\n  sriov_numvfs_store+0xfe/0x140\n  kernfs_fop_write_iter+0x11c/0x1b0\n  new_sync_write+0x11f/0x1b0\n  vfs_write+0x1eb/0x280\n  ksys_write+0x5f/0xe0\n  do_syscall_64+0x5c/0x80\n  entry_SYSCALL_64_after_hwframe+0x44/0xae","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-416"],"references":["https://git.kernel.org/stable/c/3199e34912d84cdfb8a93a984c5ae5c73fb13e84","https://git.kernel.org/stable/c/58d93e9d160c0de6d867c7eb4c2206671a351eb1","https://git.kernel.org/stable/c/9c854ae512b89229aeee93849e9bd4c115b37909","https://git.kernel.org/stable/c/bcad880865bfb421885364b1f0c7351280fe2b97","https://git.kernel.org/stable/c/c2240500817b3b4b996cdf2a461a3a5679f49b94"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:59:48.811064707+00:00"},"epss":{"cve":"CVE-2022-49626","score":0.00276,"percentile":0.20083,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}