| 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-2024-42271: net/iucv: fix use after free in iucv_sock_close() |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| net/iucv: fix use after free in iucv_sock_close() |
| |
| iucv_sever_path() is called from process context and from bh context. |
| iucv->path is used as indicator whether somebody else is taking care of |
| severing the path (or it is already removed / never existed). |
| This needs to be done with atomic compare and swap, otherwise there is a |
| small window where iucv_sock_close() will try to work with a path that has |
| already been severed and freed by iucv_callback_connrej() called by |
| iucv_tasklet_fn(). |
| |
| Example: |
| [452744.123844] Call Trace: |
| [452744.123845] ([<0000001e87f03880>] 0x1e87f03880) |
| [452744.123966] [<00000000d593001e>] iucv_path_sever+0x96/0x138 |
| [452744.124330] [<000003ff801ddbca>] iucv_sever_path+0xc2/0xd0 [af_iucv] |
| [452744.124336] [<000003ff801e01b6>] iucv_sock_close+0xa6/0x310 [af_iucv] |
| [452744.124341] [<000003ff801e08cc>] iucv_sock_release+0x3c/0xd0 [af_iucv] |
| [452744.124345] [<00000000d574794e>] __sock_release+0x5e/0xe8 |
| [452744.124815] [<00000000d5747a0c>] sock_close+0x34/0x48 |
| [452744.124820] [<00000000d5421642>] __fput+0xba/0x268 |
| [452744.124826] [<00000000d51b382c>] task_work_run+0xbc/0xf0 |
| [452744.124832] [<00000000d5145710>] do_notify_resume+0x88/0x90 |
| [452744.124841] [<00000000d5978096>] system_call+0xe2/0x2c8 |
| [452744.125319] Last Breaking-Event-Address: |
| [452744.125321] [<00000000d5930018>] iucv_path_sever+0x90/0x138 |
| [452744.125324] |
| [452744.125325] Kernel panic - not syncing: Fatal exception in interrupt |
| |
| Note that bh_lock_sock() is not serializing the tasklet context against |
| process context, because the check for sock_owned_by_user() and |
| corresponding handling is missing. |
| |
| Ideas for a future clean-up patch: |
| A) Correct usage of bh_lock_sock() in tasklet context, as described in |
| Re-enqueue, if needed. This may require adding return values to the |
| tasklet functions and thus changes to all users of iucv. |
| |
| B) Change iucv tasklet into worker and use only lock_sock() in af_iucv. |
| |
| The Linux kernel CVE team has assigned CVE-2024-42271 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 3.4 with commit 7d316b9453523498246e9e19a659c423d4c5081e and fixed in 4.19.320 with commit 84f40b46787ecb67c7ad08a5bb1376141fa10c01 |
| Issue introduced in 3.4 with commit 7d316b9453523498246e9e19a659c423d4c5081e and fixed in 5.4.282 with commit 37652fbef9809411cea55ea5fa1a170e299efcd0 |
| Issue introduced in 3.4 with commit 7d316b9453523498246e9e19a659c423d4c5081e and fixed in 5.10.224 with commit c65f72eec60a34ace031426e04e9aff8e5f04895 |
| Issue introduced in 3.4 with commit 7d316b9453523498246e9e19a659c423d4c5081e and fixed in 5.15.165 with commit ac758e1f663fe9bc64f6b47212a2aa18697524f5 |
| Issue introduced in 3.4 with commit 7d316b9453523498246e9e19a659c423d4c5081e and fixed in 6.1.104 with commit 8b424c9e44111c5a76f41c6b741f8d4c4179d876 |
| Issue introduced in 3.4 with commit 7d316b9453523498246e9e19a659c423d4c5081e and fixed in 6.6.45 with commit 01437282fd3904810603f3dc98d2cac6b8b6fc84 |
| Issue introduced in 3.4 with commit 7d316b9453523498246e9e19a659c423d4c5081e and fixed in 6.10.4 with commit 69620522c48ce8215e5eb55ffbab8cafee8f407d |
| Issue introduced in 3.4 with commit 7d316b9453523498246e9e19a659c423d4c5081e and fixed in 6.11 with commit f558120cd709682b739207b48cf7479fd9568431 |
| |
| 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-2024-42271 |
| 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/iucv/af_iucv.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/84f40b46787ecb67c7ad08a5bb1376141fa10c01 |
| https://git.kernel.org/stable/c/37652fbef9809411cea55ea5fa1a170e299efcd0 |
| https://git.kernel.org/stable/c/c65f72eec60a34ace031426e04e9aff8e5f04895 |
| https://git.kernel.org/stable/c/ac758e1f663fe9bc64f6b47212a2aa18697524f5 |
| https://git.kernel.org/stable/c/8b424c9e44111c5a76f41c6b741f8d4c4179d876 |
| https://git.kernel.org/stable/c/01437282fd3904810603f3dc98d2cac6b8b6fc84 |
| https://git.kernel.org/stable/c/69620522c48ce8215e5eb55ffbab8cafee8f407d |
| https://git.kernel.org/stable/c/f558120cd709682b739207b48cf7479fd9568431 |
