| 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-2021-47248: udp: fix race between close() and udp_abort() |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| udp: fix race between close() and udp_abort() |
| |
| Kaustubh reported and diagnosed a panic in udp_lib_lookup(). |
| The root cause is udp_abort() racing with close(). Both |
| racing functions acquire the socket lock, but udp{v6}_destroy_sock() |
| release it before performing destructive actions. |
| |
| We can't easily extend the socket lock scope to avoid the race, |
| instead use the SOCK_DEAD flag to prevent udp_abort from doing |
| any action when the critical race happens. |
| |
| Diagnosed-and-tested-by: Kaustubh Pandey <kapandey@codeaurora.org> |
| |
| The Linux kernel CVE team has assigned CVE-2021-47248 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 4.9 with commit 5d77dca82839ef016a93ad7acd7058b14d967752 and fixed in 4.9.274 with commit e3c36c773aed0fef8b1d3d555b43393ec564400f |
| Issue introduced in 4.9 with commit 5d77dca82839ef016a93ad7acd7058b14d967752 and fixed in 4.14.238 with commit a0882f68f54f7a8b6308261acee9bd4faab5a69e |
| Issue introduced in 4.9 with commit 5d77dca82839ef016a93ad7acd7058b14d967752 and fixed in 4.19.196 with commit 2f73448041bd0682d4b552cfd314ace66107f1ad |
| Issue introduced in 4.9 with commit 5d77dca82839ef016a93ad7acd7058b14d967752 and fixed in 5.4.128 with commit 5a88477c1c85e4baa51e91f2d40f2166235daa56 |
| Issue introduced in 4.9 with commit 5d77dca82839ef016a93ad7acd7058b14d967752 and fixed in 5.10.46 with commit 8729ec8a2238152a4afc212a331a6cd2c61aeeac |
| Issue introduced in 4.9 with commit 5d77dca82839ef016a93ad7acd7058b14d967752 and fixed in 5.12.13 with commit 65310b0aff86980a011c7c7bfa487a333d4ca241 |
| Issue introduced in 4.9 with commit 5d77dca82839ef016a93ad7acd7058b14d967752 and fixed in 5.13 with commit a8b897c7bcd47f4147d066e22cc01d1026d7640e |
| |
| 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-2021-47248 |
| 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/ipv4/udp.c |
| net/ipv6/udp.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/e3c36c773aed0fef8b1d3d555b43393ec564400f |
| https://git.kernel.org/stable/c/a0882f68f54f7a8b6308261acee9bd4faab5a69e |
| https://git.kernel.org/stable/c/2f73448041bd0682d4b552cfd314ace66107f1ad |
| https://git.kernel.org/stable/c/5a88477c1c85e4baa51e91f2d40f2166235daa56 |
| https://git.kernel.org/stable/c/8729ec8a2238152a4afc212a331a6cd2c61aeeac |
| https://git.kernel.org/stable/c/65310b0aff86980a011c7c7bfa487a333d4ca241 |
| https://git.kernel.org/stable/c/a8b897c7bcd47f4147d066e22cc01d1026d7640e |
