CVE-2024-56621 Information

Description

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().

Reference

https://git.kernel.org/stable/c/1695c4361d35b7bdadd7b34f99c9c07741e181e5 https://git.kernel.org/stable/c/2e7a3bb0331efb292e0fb022c36bc592137f0520