| 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-2022-49065: SUNRPC: Fix the svc_deferred_event trace class |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| SUNRPC: Fix the svc_deferred_event trace class |
| |
| Fix a NULL deref crash that occurs when an svc_rqst is deferred |
| while the sunrpc tracing subsystem is enabled. svc_revisit() sets |
| dr->xprt to NULL, so it can't be relied upon in the tracepoint to |
| provide the remote's address. |
| |
| Unfortunately we can't revert the "svc_deferred_class" hunk in |
| commit ece200ddd54b ("sunrpc: Save remote presentation address in |
| svc_xprt for trace events") because there is now a specific check |
| of event format specifiers for unsafe dereferences. The warning |
| that check emits is: |
| |
| event svc_defer_recv has unsafe dereference of argument 1 |
| |
| A "%pISpc" format specifier with a "struct sockaddr *" is indeed |
| flagged by this check. |
| |
| Instead, take the brute-force approach used by the svcrdma_qp_error |
| tracepoint. Convert the dr::addr field into a presentation address |
| in the TP_fast_assign() arm of the trace event, and store that as |
| a string. This fix can be backported to -stable kernels. |
| |
| In the meantime, commit c6ced22997ad ("tracing: Update print fmt |
| check to handle new __get_sockaddr() macro") is now in v5.18, so |
| this wonky fix can be replaced with __sockaddr() and friends |
| properly during the v5.19 merge window. |
| |
| The Linux kernel CVE team has assigned CVE-2022-49065 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 4.17 with commit ece200ddd54b9ce840cfee554fb812560c545c7d and fixed in 5.10.112 with commit 85ee17ca21cf92989e8c923e3ea4514c291e9d38 |
| Issue introduced in 4.17 with commit ece200ddd54b9ce840cfee554fb812560c545c7d and fixed in 5.15.35 with commit 726ae7300fcc25fefa46d188cc07eb16dc908f9e |
| Issue introduced in 4.17 with commit ece200ddd54b9ce840cfee554fb812560c545c7d and fixed in 5.17.4 with commit c2456f470eea3bd06574d988bf6089e7c3f4c5cc |
| Issue introduced in 4.17 with commit ece200ddd54b9ce840cfee554fb812560c545c7d and fixed in 5.18 with commit 4d5004451ab2218eab94a30e1841462c9316ba19 |
| |
| 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-2022-49065 |
| 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: |
| include/trace/events/sunrpc.h |
| |
| |
| 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/85ee17ca21cf92989e8c923e3ea4514c291e9d38 |
| https://git.kernel.org/stable/c/726ae7300fcc25fefa46d188cc07eb16dc908f9e |
| https://git.kernel.org/stable/c/c2456f470eea3bd06574d988bf6089e7c3f4c5cc |
| https://git.kernel.org/stable/c/4d5004451ab2218eab94a30e1841462c9316ba19 |
