| From bippy-1.1.0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@kernel.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2022-49309: drivers: staging: rtl8723bs: Fix deadlock in rtw_surveydone_event_callback() |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| drivers: staging: rtl8723bs: Fix deadlock in rtw_surveydone_event_callback() |
| |
| There is a deadlock in rtw_surveydone_event_callback(), |
| which is shown below: |
| |
| (Thread 1) | (Thread 2) |
| | _set_timer() |
| rtw_surveydone_event_callback()| mod_timer() |
| spin_lock_bh() //(1) | (wait a time) |
| ... | rtw_scan_timeout_handler() |
| del_timer_sync() | spin_lock_bh() //(2) |
| (wait timer to stop) | ... |
| |
| We hold pmlmepriv->lock in position (1) of thread 1 and use |
| del_timer_sync() to wait timer to stop, but timer handler |
| also need pmlmepriv->lock in position (2) of thread 2. |
| As a result, rtw_surveydone_event_callback() will block forever. |
| |
| This patch extracts del_timer_sync() from the protection of |
| spin_lock_bh(), which could let timer handler to obtain |
| the needed lock. What`s more, we change spin_lock_bh() in |
| rtw_scan_timeout_handler() to spin_lock_irq(). Otherwise, |
| spin_lock_bh() will also cause deadlock() in timer handler. |
| |
| The Linux kernel CVE team has assigned CVE-2022-49309 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 4.12 with commit 554c0a3abf216c991c5ebddcdb2c08689ecd290b and fixed in 5.10.237 with commit c84e5c819600ee0628f61b33d145258ae0f3d7a7 |
| Issue introduced in 4.12 with commit 554c0a3abf216c991c5ebddcdb2c08689ecd290b and fixed in 5.15.47 with commit f89f6c3ebf69623b8ea48200bd690e9e210335a1 |
| Issue introduced in 4.12 with commit 554c0a3abf216c991c5ebddcdb2c08689ecd290b and fixed in 5.17.15 with commit ce129d3efd181da5fd56f4360cc8827122afa67e |
| Issue introduced in 4.12 with commit 554c0a3abf216c991c5ebddcdb2c08689ecd290b and fixed in 5.18.4 with commit 2c41f5c341853f84b7bc2f32605d4e2782e8c279 |
| Issue introduced in 4.12 with commit 554c0a3abf216c991c5ebddcdb2c08689ecd290b and fixed in 5.19 with commit cc7ad0d77b51c872d629bcd98aea463a3c4109e7 |
| |
| 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-2022-49309 |
| 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/staging/rtl8723bs/core/rtw_mlme.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/c84e5c819600ee0628f61b33d145258ae0f3d7a7 |
| https://git.kernel.org/stable/c/f89f6c3ebf69623b8ea48200bd690e9e210335a1 |
| https://git.kernel.org/stable/c/ce129d3efd181da5fd56f4360cc8827122afa67e |
| https://git.kernel.org/stable/c/2c41f5c341853f84b7bc2f32605d4e2782e8c279 |
| https://git.kernel.org/stable/c/cc7ad0d77b51c872d629bcd98aea463a3c4109e7 |
