| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2022-49626: sfc: fix use after free when disabling sriov |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| sfc: fix use after free when disabling sriov |
| |
| Use after free is detected by kfence when disabling sriov. What was read |
| after being freed was vf->pci_dev: it was freed from pci_disable_sriov |
| and later read in efx_ef10_sriov_free_vf_vports, called from |
| efx_ef10_sriov_free_vf_vswitching. |
| |
| Set the pointer to NULL at release time to not trying to read it later. |
| |
| Reproducer and dmesg log (note that kfence doesn't detect it every time): |
| $ echo 1 > /sys/class/net/enp65s0f0np0/device/sriov_numvfs |
| $ echo 0 > /sys/class/net/enp65s0f0np0/device/sriov_numvfs |
| |
| BUG: KFENCE: use-after-free read in efx_ef10_sriov_free_vf_vswitching+0x82/0x170 [sfc] |
| |
| Use-after-free read at 0x00000000ff3c1ba5 (in kfence-#224): |
| efx_ef10_sriov_free_vf_vswitching+0x82/0x170 [sfc] |
| efx_ef10_pci_sriov_disable+0x38/0x70 [sfc] |
| efx_pci_sriov_configure+0x24/0x40 [sfc] |
| sriov_numvfs_store+0xfe/0x140 |
| kernfs_fop_write_iter+0x11c/0x1b0 |
| new_sync_write+0x11f/0x1b0 |
| vfs_write+0x1eb/0x280 |
| ksys_write+0x5f/0xe0 |
| do_syscall_64+0x5c/0x80 |
| entry_SYSCALL_64_after_hwframe+0x44/0xae |
| |
| kfence-#224: 0x00000000edb8ef95-0x00000000671f5ce1, size=2792, cache=kmalloc-4k |
| |
| allocated by task 6771 on cpu 10 at 3137.860196s: |
| pci_alloc_dev+0x21/0x60 |
| pci_iov_add_virtfn+0x2a2/0x320 |
| sriov_enable+0x212/0x3e0 |
| efx_ef10_sriov_configure+0x67/0x80 [sfc] |
| efx_pci_sriov_configure+0x24/0x40 [sfc] |
| sriov_numvfs_store+0xba/0x140 |
| kernfs_fop_write_iter+0x11c/0x1b0 |
| new_sync_write+0x11f/0x1b0 |
| vfs_write+0x1eb/0x280 |
| ksys_write+0x5f/0xe0 |
| do_syscall_64+0x5c/0x80 |
| entry_SYSCALL_64_after_hwframe+0x44/0xae |
| |
| freed by task 6771 on cpu 12 at 3170.991309s: |
| device_release+0x34/0x90 |
| kobject_cleanup+0x3a/0x130 |
| pci_iov_remove_virtfn+0xd9/0x120 |
| sriov_disable+0x30/0xe0 |
| efx_ef10_pci_sriov_disable+0x57/0x70 [sfc] |
| efx_pci_sriov_configure+0x24/0x40 [sfc] |
| sriov_numvfs_store+0xfe/0x140 |
| kernfs_fop_write_iter+0x11c/0x1b0 |
| new_sync_write+0x11f/0x1b0 |
| vfs_write+0x1eb/0x280 |
| ksys_write+0x5f/0xe0 |
| do_syscall_64+0x5c/0x80 |
| entry_SYSCALL_64_after_hwframe+0x44/0xae |
| |
| The Linux kernel CVE team has assigned CVE-2022-49626 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 4.2 with commit 3c5eb87605e85146a78de589b5070a37862425db and fixed in 4.9.324 with commit 3199e34912d84cdfb8a93a984c5ae5c73fb13e84 |
| Issue introduced in 4.2 with commit 3c5eb87605e85146a78de589b5070a37862425db and fixed in 4.14.289 with commit c9e75bb22a26e391f189f5a5133dd63dcb57fdaa |
| Issue introduced in 4.2 with commit 3c5eb87605e85146a78de589b5070a37862425db and fixed in 4.19.253 with commit 9c854ae512b89229aeee93849e9bd4c115b37909 |
| Issue introduced in 4.2 with commit 3c5eb87605e85146a78de589b5070a37862425db and fixed in 5.4.207 with commit bcad880865bfb421885364b1f0c7351280fe2b97 |
| Issue introduced in 4.2 with commit 3c5eb87605e85146a78de589b5070a37862425db and fixed in 5.10.132 with commit c2240500817b3b4b996cdf2a461a3a5679f49b94 |
| Issue introduced in 4.2 with commit 3c5eb87605e85146a78de589b5070a37862425db and fixed in 5.15.56 with commit 58d93e9d160c0de6d867c7eb4c2206671a351eb1 |
| Issue introduced in 4.2 with commit 3c5eb87605e85146a78de589b5070a37862425db and fixed in 5.18.13 with commit e435c4aeeaa073091f7f3b7735af2ef5c97d63f2 |
| Issue introduced in 4.2 with commit 3c5eb87605e85146a78de589b5070a37862425db and fixed in 5.19 with commit ebe41da5d47ac0fff877e57bd14c54dccf168827 |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2022-49626 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| drivers/net/ethernet/sfc/ef10_sriov.c |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| https://git.kernel.org/stable/c/3199e34912d84cdfb8a93a984c5ae5c73fb13e84 |
| https://git.kernel.org/stable/c/c9e75bb22a26e391f189f5a5133dd63dcb57fdaa |
| https://git.kernel.org/stable/c/9c854ae512b89229aeee93849e9bd4c115b37909 |
| https://git.kernel.org/stable/c/bcad880865bfb421885364b1f0c7351280fe2b97 |
| https://git.kernel.org/stable/c/c2240500817b3b4b996cdf2a461a3a5679f49b94 |
| https://git.kernel.org/stable/c/58d93e9d160c0de6d867c7eb4c2206671a351eb1 |
| https://git.kernel.org/stable/c/e435c4aeeaa073091f7f3b7735af2ef5c97d63f2 |
| https://git.kernel.org/stable/c/ebe41da5d47ac0fff877e57bd14c54dccf168827 |
