NULL pointer dereference in Linux

CVE-2024-56621

In the Linux kernel, the following vulnerability has been resolved: scsi: ufs: core: Cancel RTC work during ufshcd_remove() Currently, RTC work is only cancelled during __ufshcd_wl_suspend(). When ufshcd is removed in ufshcd_remove(), RTC work is not cancelled. Due to this, any further trigger of the RTC work after ufshcd_remove() would result in a NULL pointer dereference as below: Unable to handle kernel NULL pointer dereference at virtual address 00000000000002a4 Workqueue: events ufshcd_rtc_work Call trace: _raw_spin_lock_irqsave+0x34/0x8c pm_runtime_get_if_active+0x24/0xb4 ufshcd_rtc_work+0x124/0x19c process_scheduled_works+0x18c/0x2d8 worker_thread+0x144/0x280 kthread+0x11c/0x128 ret_from_fork+0x10/0x20 Since RTC work accesses the ufshcd internal structures, it should be cancelled when ufshcd is removed. So do that in ufshcd_remove(), as per the order in ufshcd_init().

EPSS: 0.002 (10.0th percentile) — read the EPSS interpretation.