Affected: Linux

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

ice: Fix crash by keep old cfg when update TCs more than queues

There are problems if allocated queues less than Traffic Classes.

Commit a632b2a4c920 ("ice: ethtool: Prohibit improper channel config for DCB") already disallow setting less queues than TCs.

Another case is if we first set less queues, and later update more TCs config due to LLDP, ice_vsi_cfg_tc() will failed but left dirty num_txq/rxq and tc_cfg in vsi, that will cause invalid pointer access.

[ 95.968089] ice 0000:3b:00.1: More TCs defined than queues/rings allocated. [ 95.968092] ice 0000:3b:00.1: Trying to use more Rx queues (8), than were allocated (1)! [ 95.968093] ice 0000:3b:00.1: Failed to config TC for VSI index: 0 [ 95.969621] general protection fault: 0000 [#1] SMP NOPTI [ 95.969705] CPU: 1 PID: 58405 Comm: lldpad Kdump: loaded Tainted: G U W O --------- -t - 4.18.0 #1 [ 95.969867] Hardware name: O.E.M/BC11SPSCB10, BIOS 8.23 12/30/2021 [ 95.969992] RIP: 0010:devm_kmalloc+0xa/0x60 [ 95.970052] Code: 5c ff ff ff 31 c0 5b 5d 41 5c c3 b8 f4 ff ff ff eb f4 0f 1f 40 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 89 d1 <8b> 97 60 02 00 00 48 8d 7e 18 48 39 f7 72 3f 55 89 ce 53 48 8b 4c [ 95.970344] RSP: 0018:ffffc9003f553888 EFLAGS: 00010206 [ 95.970425] RAX: dead000000000200 RBX: ffffea003c425b00 RCX: 00000000006080c0 [ 95.970536] RDX: 00000000006080c0 RSI: 0000000000000200 RDI: dead0000000002…