| 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-2021-47559: net/smc: Fix NULL pointer dereferencing in smc_vlan_by_tcpsk() |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| net/smc: Fix NULL pointer dereferencing in smc_vlan_by_tcpsk() |
| |
| Coverity reports a possible NULL dereferencing problem: |
| |
| in smc_vlan_by_tcpsk(): |
| 6. returned_null: netdev_lower_get_next returns NULL (checked 29 out of 30 times). |
| 7. var_assigned: Assigning: ndev = NULL return value from netdev_lower_get_next. |
| 1623 ndev = (struct net_device *)netdev_lower_get_next(ndev, &lower); |
| CID 1468509 (#1 of 1): Dereference null return value (NULL_RETURNS) |
| 8. dereference: Dereferencing a pointer that might be NULL ndev when calling is_vlan_dev. |
| 1624 if (is_vlan_dev(ndev)) { |
| |
| Remove the manual implementation and use netdev_walk_all_lower_dev() to |
| iterate over the lower devices. While on it remove an obsolete function |
| parameter comment. |
| |
| The Linux kernel CVE team has assigned CVE-2021-47559 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 4.18 with commit cb9d43f6775457cac75544bc4197f26ac2b6f294 and fixed in 5.10.83 with commit c94cbd262b6aa3b54d73a1ed1f9c0d19df57f4ff |
| Issue introduced in 4.18 with commit cb9d43f6775457cac75544bc4197f26ac2b6f294 and fixed in 5.15.6 with commit bb851d0fb02547d03cd40106b5f2391c4fed6ed1 |
| Issue introduced in 4.18 with commit cb9d43f6775457cac75544bc4197f26ac2b6f294 and fixed in 5.16 with commit 587acad41f1bc48e16f42bb2aca63bf323380be8 |
| |
| 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-2021-47559 |
| 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: |
| net/smc/smc_core.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/c94cbd262b6aa3b54d73a1ed1f9c0d19df57f4ff |
| https://git.kernel.org/stable/c/bb851d0fb02547d03cd40106b5f2391c4fed6ed1 |
| https://git.kernel.org/stable/c/587acad41f1bc48e16f42bb2aca63bf323380be8 |
