In the Linux kernel, the following vulnerability has been resolved: can: mcp251x: fix deadlock...

In the Linux kernel, the following vulnerability has been resolved:

can: mcp251x: fix deadlock in error path of mcp251x_open

The mcp251x_open() function call free_irq() in its error path with the mpc_lock mutex held. But if an interrupt already occurred the interrupt handler will be waiting for the mpc_lock and free_irq() will deadlock waiting for the handler to finish.

This issue is similar to the one fixed in commit 7dd9c26bd6cf ("can: mcp251x: fix deadlock if an interrupt occurs during mcp251x_open") but for the error path.

To solve this issue move the call to free_irq() after the lock is released. Setting priv->force_quit = 1 beforehand ensure that the IRQ handler will exit right away once it acquired the lock.