| 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-2022-48872: misc: fastrpc: Fix use-after-free race condition for maps |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| misc: fastrpc: Fix use-after-free race condition for maps |
| |
| It is possible that in between calling fastrpc_map_get() until |
| map->fl->lock is taken in fastrpc_free_map(), another thread can call |
| fastrpc_map_lookup() and get a reference to a map that is about to be |
| deleted. |
| |
| Rewrite fastrpc_map_get() to only increase the reference count of a map |
| if it's non-zero. Propagate this to callers so they can know if a map is |
| about to be deleted. |
| |
| Fixes this warning: |
| refcount_t: addition on 0; use-after-free. |
| WARNING: CPU: 5 PID: 10100 at lib/refcount.c:25 refcount_warn_saturate |
| ... |
| Call trace: |
| refcount_warn_saturate |
| [fastrpc_map_get inlined] |
| [fastrpc_map_lookup inlined] |
| fastrpc_map_create |
| fastrpc_internal_invoke |
| fastrpc_device_ioctl |
| __arm64_sys_ioctl |
| invoke_syscall |
| |
| The Linux kernel CVE team has assigned CVE-2022-48872 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.1 with commit c68cfb718c8f97b7f7a50ed66be5feb42d0c8988 and fixed in 5.4.230 with commit 556dfdb226ce1e5231d8836159b23f8bb0395bf4 |
| Issue introduced in 5.1 with commit c68cfb718c8f97b7f7a50ed66be5feb42d0c8988 and fixed in 5.10.165 with commit b171d0d2cf1b8387c72c8d325c5d5746fa271e39 |
| Issue introduced in 5.1 with commit c68cfb718c8f97b7f7a50ed66be5feb42d0c8988 and fixed in 5.15.90 with commit 61a0890cb95afec5c8a2f4a879de2b6220984ef1 |
| Issue introduced in 5.1 with commit c68cfb718c8f97b7f7a50ed66be5feb42d0c8988 and fixed in 6.1.8 with commit 079c78c68714f7d8d58e66c477b0243b31806907 |
| Issue introduced in 5.1 with commit c68cfb718c8f97b7f7a50ed66be5feb42d0c8988 and fixed in 6.2 with commit 96b328d119eca7563c1edcc4e1039a62e6370ecb |
| |
| 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-2022-48872 |
| 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: |
| drivers/misc/fastrpc.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/556dfdb226ce1e5231d8836159b23f8bb0395bf4 |
| https://git.kernel.org/stable/c/b171d0d2cf1b8387c72c8d325c5d5746fa271e39 |
| https://git.kernel.org/stable/c/61a0890cb95afec5c8a2f4a879de2b6220984ef1 |
| https://git.kernel.org/stable/c/079c78c68714f7d8d58e66c477b0243b31806907 |
| https://git.kernel.org/stable/c/96b328d119eca7563c1edcc4e1039a62e6370ecb |
