LinuxVULNRICHMENT:CVE-2021-47321CVE-2021-47321 watchdog: Fix possible use-after-free by calling del_timer_sync()
In the Linux kernel, the following vulnerability has been resolved:
watchdog: Fix possible use-after-free by calling del_timer_sync()
This driver’s remove path calls del_timer(). However, that function
does not wait until the timer handler finishes. This means that the
timer handler may still be running after the driver’s remove function
has finished, which would result in a use-after-free.
Fix by calling del_timer_sync(), which makes sure the timer handler
has finished, and unable to re-schedule itself.
References
git.kernel.org/stable/c/1a053c4d716898a53c2e31c574a70ea0c37044a3
git.kernel.org/stable/c/4c05dac488a660fe2925c047ecb119e7afaaeb1e
git.kernel.org/stable/c/58606882ad8ec6c39e0f40344b922921ef94ab4d
git.kernel.org/stable/c/66ba9cf929b1c4fabf545bd4c18f6f64e23e46e4
git.kernel.org/stable/c/8bec568d7518b1504a602ed5376bb322e4dbb270
git.kernel.org/stable/c/ca96b8ea5e74956071154bdb456778cc3027e79f
git.kernel.org/stable/c/d0212f095ab56672f6f36aabc605bda205e1e0bf
git.kernel.org/stable/c/db222f1477ad5692cd454709b714949807e5d111
git.kernel.org/stable/c/ecd620e0fb1ff7f78fdb593379b2e6938c99707a
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SSVC
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none
Automatable
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partial