CVE-2022-49096CVE-2022-49096

In the Linux kernel, the following vulnerability has been resolved: net: sfc: add missing xdp queue reinitialization After rx/tx ring buffer size is changed, kernel panic occurs when it acts XDP_TX or XDP_REDIRECT. When tx/rx ring buffer size is changed(ethtool -G), sfc driver reallocates and reinitializes rx and tx queues and their buffer (tx_queue->buffer). But it misses reinitializing xdp queues(efx->xdp_tx_queues). So, while it is acting XDP_TX or XDP_REDIRECT, it uses the uninitialized tx_queue->buffer. A new function efx_set_xdp_channels() is separated from efx_set_channels() to handle only xdp queues. Splat looks like: BUG: kernel NULL pointer dereference, address: 000000000000002a #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: 0002 [#4] PREEMPT SMP NOPTI RIP: 0010:efx_tx_map_chunk+0x54/0x90 [sfc] CPU: 2 PID: 0 Comm: swapper/2 Tainted: G D 5.17.0+ #55 e8beeee8289528f11357029357cf