CVE-2024-46791 Information

Description

In the Linux kernel the following vulnerability has been resolved:

can: mcp251x: fix deadlock if an interrupt occurs during mcp251x_open

The mcp251x_hw_wake() function is called with the mpc_lock mutex held and disables the interrupt handler so that no interrupts can be processed while waking the device. If an interrupt has already occurred then waiting for the interrupt handler to complete will deadlock because it will be trying to acquire the same mutex.

CPU0 CPU1

mcp251x_open() mutex_lock(&priv->mcp_lock) request_threaded_irq() mcp251x_can_ist() mutex_lock(&priv->mcp_lock) mcp251x_hw_wake() disable_irq() <– deadlock

Use disable_irq_nosync() instead because the interrupt handler does everything while holding the mutex so it doesn’t matter if it’s still running.

Reference

https://git.kernel.org/stable/c/3a49b6b1caf5cefc05264d29079d52c99cb188e0 https://git.kernel.org/stable/c/513c8fc189b52f7922e36bdca58997482b198f0e https://git.kernel.org/stable/c/f7ab9e14b23a3eac6714bdc4dba244d8aa1ef646 https://git.kernel.org/stable/c/8fecde9c3f9a4b97b68bb97c9f47e5b662586ba7 https://git.kernel.org/stable/c/e554113a1cd2a9cfc6c7af7bdea2141c5757e188 https://git.kernel.org/stable/c/7dd9c26bd6cf679bcfdef01a8659791aa6487a29