net: netpoll: initialize work queue before error checks

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: net: netpoll: initialize work queue before error checks Prevent a kernel warning when netconsole setup fails on devices with IFF_DISABLE_NETPOLL flag. The warning (at kernel/workqueue.c:4242 in __flush_work) occurs because the cleanup path tries to cancel an uninitialized work queue. When __netpoll_setup() encounters a device with IFF_DISABLE_NETPOLL, it fails early and calls skb_pool_flush() for cleanup. This function calls cancel_work_sync(&np->refill_wq), but refill_wq hasn't been initialized yet, triggering the warning. Move INIT_WORK() to the beginning of __netpoll_setup(), ensuring the work queue is properly initialized before any potential failure points. This allows the cleanup path to safely cancel the work queue regardless of where the setup fails.

References

• https://git.kernel.org/stable/c/a90d0dc38a10347078cca60e7495ad0648838f18
• https://git.kernel.org/stable/c/760bc6ceda8e2c273c0e2018ad2595967c3dd308
• https://git.kernel.org/stable/c/e5235eb6cfe02a51256013a78f7b28779a7740d5