CVE-2022-48647

In the Linux kernel, the following vulnerability has been resolved: sfc:
fix TX channel offset when using legacy interrupts In legacy interrupt mode
the tx_channel_offset was hardcoded to 1, but that’s not correct if
efx_sepparate_tx_channels is false. In that case, the offset is 0 because
the tx queues are in the single existing channel at index 0, together with
the rx queue. Without this fix, as soon as you try to send any traffic, it
tries to get the tx queues from an uninitialized channel getting these
errors: WARNING: CPU: 1 PID: 0 at drivers/net/ethernet/sfc/tx.c:540
efx_hard_start_xmit+0x12e/0x170 [sfc] […] RIP:
0010:efx_hard_start_xmit+0x12e/0x170 [sfc] […] Call Trace: <IRQ>
dev_hard_start_xmit+0xd7/0x230 sch_direct_xmit+0x9f/0x360
__dev_queue_xmit+0x890/0xa40 […] BUG: unable to handle kernel NULL
pointer dereference at 0000000000000020 […] RIP:
0010:efx_hard_start_xmit+0x153/0x170 [sfc] […] Call Trace: <IRQ>
dev_hard_start_xmit+0xd7/0x230 sch_direct_xmit+0x9f/0x360
__dev_queue_xmit+0x890/0xa40 […]