| 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-2023-52775: net/smc: avoid data corruption caused by decline |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| net/smc: avoid data corruption caused by decline |
| |
| We found a data corruption issue during testing of SMC-R on Redis |
| applications. |
| |
| The benchmark has a low probability of reporting a strange error as |
| shown below. |
| |
| "Error: Protocol error, got "\xe2" as reply type byte" |
| |
| Finally, we found that the retrieved error data was as follows: |
| |
| 0xE2 0xD4 0xC3 0xD9 0x04 0x00 0x2C 0x20 0xA6 0x56 0x00 0x16 0x3E 0x0C |
| 0xCB 0x04 0x02 0x01 0x00 0x00 0x20 0x00 0x00 0x00 0x00 0x00 0x00 0x00 |
| 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00 0xE2 |
| |
| It is quite obvious that this is a SMC DECLINE message, which means that |
| the applications received SMC protocol message. |
| We found that this was caused by the following situations: |
| |
| client server |
| ¦ clc proposal |
| -------------> |
| ¦ clc accept |
| <------------- |
| ¦ clc confirm |
| -------------> |
| wait llc confirm |
| send llc confirm |
| ¦failed llc confirm |
| ¦ x------ |
| (after 2s)timeout |
| wait llc confirm rsp |
| |
| wait decline |
| |
| (after 1s) timeout |
| (after 2s) timeout |
| ¦ decline |
| --------------> |
| ¦ decline |
| <-------------- |
| |
| As a result, a decline message was sent in the implementation, and this |
| message was read from TCP by the already-fallback connection. |
| |
| This patch double the client timeout as 2x of the server value, |
| With this simple change, the Decline messages should never cross or |
| collide (during Confirm link timeout). |
| |
| This issue requires an immediate solution, since the protocol updates |
| involve a more long-term solution. |
| |
| The Linux kernel CVE team has assigned CVE-2023-52775 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.8 with commit 0fb0b02bd6fd26cba38002be4a6bbcae2228fd44 and fixed in 5.10.203 with commit 5ada292b5c504720a0acef8cae9acc62a694d19c |
| Issue introduced in 5.8 with commit 0fb0b02bd6fd26cba38002be4a6bbcae2228fd44 and fixed in 5.15.141 with commit 90072af9efe8c7bd7d086709014ddd44cebd5e7c |
| Issue introduced in 5.8 with commit 0fb0b02bd6fd26cba38002be4a6bbcae2228fd44 and fixed in 6.1.65 with commit 94a0ae698b4d5d5bb598e23228002a1491c50add |
| Issue introduced in 5.8 with commit 0fb0b02bd6fd26cba38002be4a6bbcae2228fd44 and fixed in 6.6.4 with commit 7234d2b5dffa5af77fd4e0deaebab509e130c6b1 |
| Issue introduced in 5.8 with commit 0fb0b02bd6fd26cba38002be4a6bbcae2228fd44 and fixed in 6.7 with commit e6d71b437abc2f249e3b6a1ae1a7228e09c6e563 |
| |
| 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-2023-52775 |
| 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/af_smc.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/5ada292b5c504720a0acef8cae9acc62a694d19c |
| https://git.kernel.org/stable/c/90072af9efe8c7bd7d086709014ddd44cebd5e7c |
| https://git.kernel.org/stable/c/94a0ae698b4d5d5bb598e23228002a1491c50add |
| https://git.kernel.org/stable/c/7234d2b5dffa5af77fd4e0deaebab509e130c6b1 |
| https://git.kernel.org/stable/c/e6d71b437abc2f249e3b6a1ae1a7228e09c6e563 |
