CVE-2023-53107: In the Linux kernel, the following vulnerability has been resolved:  veth: Fix use after free in XDP_REDIRECT  Commit 718a18a0c8a6 ("veth: Rework veth_xdp_rcv_skb in order to accept non-linear skb") introduced a bug where it tried to use pskb_expand_head() if the headroom was less than XDP_PACKET_HEADROOM.  This however uses kmalloc to expand the head, which will later allow consume_skb() to free the skb while is it still in use by AF_XDP.  Previously if the headroom was less than XDP_PACKET_HEADROOM we continued on to allocate a new skb from pages so this restores that behavior.  BUG: KASAN: use-after-free in __xsk_rcv+0x18d/0x2c0 Read of size 78 at addr ffff888976250154 by task napi/iconduit-g/148640  CPU: 5 PID: 148640 Comm: napi/iconduit-g Kdump: loaded Tainted: G           O       6.1.4-cloudflare-kasan-2023.1.2 #1 Hardware name: Quanta Computer Inc. QuantaPlex T41S-2U/S2S-MB, BIOS S2S_3B10.03 06/21/2018 Call Trace:   <TASK>   dump_stack_lvl+0x34/0x48   print_report+0x170/0x473   ? __xsk_rcv+0x18d/0x2c0   kasan_report+0xad/0x130   ? __xsk_rcv+0x18d/0x2c0   kasan_check_range+0x149/0x1a0   memcpy+0x20/0x60   __xsk_rcv+0x18d/0x2c0   __xsk_map_redirect+0x1f3/0x490   ? veth_xdp_rcv_skb+0x89c/0x1ba0 [veth]   xdp_do_redirect+0x5ca/0xd60   veth_xdp_rcv_skb+0x935/0x1ba0 [veth]   ? __netif_receive_skb_list_core+0x671/0x920   ? veth_xdp+0x670/0x670 [veth]   veth_xdp_rcv+0x304/0xa20 [veth]   ? do_xdp_generic+0x150/0x150   ? veth_xdp_rcv_one+0xde0/0xde0 [veth]   ? _raw_spin_lock_bh+0xe0/0xe0   ? newidle_balance+0x887/0xe30   ? __perf_event_task_sched_in+0xdb/0x800   veth_poll+0x139/0x571 [veth]   ? veth_xdp_rcv+0xa20/0xa20 [veth]   ? _raw_spin_unlock+0x39/0x70   ? finish_task_switch.isra.0+0x17e/0x7d0   ? __switch_to+0x5cf/0x1070   ? __schedule+0x95b/0x2640   ? io_schedule_timeout+0x160/0x160   __napi_poll+0xa1/0x440   napi_threaded_poll+0x3d1/0x460   ? __napi_poll+0x440/0x440   ? __kthread_parkme+0xc6/0x1f0   ? __napi_poll+0x440/0x440   kthread+0x2a2/0x340   ? kthread_complete_and_exit+0x20/0x20   ret_from_fork+0x22/0x30   </TASK>  Freed by task 148640:   kasan_save_stack+0x23/0x50   kasan_set_track+0x21/0x30   kasan_save_free_info+0x2a/0x40   ____kasan_slab_free+0x169/0x1d0   slab_free_freelist_hook+0xd2/0x190   __kmem_cache_free+0x1a1/0x2f0   skb_release_data+0x449/0x600   consume_skb+0x9f/0x1c0   veth_xdp_rcv_skb+0x89c/0x1ba0 [veth]   veth_xdp_rcv+0x304/0xa20 [veth]   veth_poll+0x139/0x571 [veth]   __napi_poll+0xa1/0x440   napi_threaded_poll+0x3d1/0x460   kthread+0x2a2/0x340   ret_from_fork+0x22/0x30  The buggy address belongs to the object at ffff888976250000   which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 340 bytes inside of   2048-byte region [ffff888976250000, ffff888976250800)  The buggy address belongs to the physical page: page:00000000ae18262a refcount:2 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x976250 head:00000000ae18262a order:3 compound_mapcount:0 compound_pincount:0 flags: 0x2ffff800010200(slab|head|node=0|zone=2|lastcpupid=0x1ffff) raw: 002ffff800010200 0000000000000000 dead000000000122 ffff88810004cf00 raw: 0000000000000000 0000000080080008 00000002ffffffff 0000000000000000 page dumped because: kasan: bad access detected  Memory state around the buggy address:   ffff888976250000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb   ffff888976250080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > ffff888976250100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb                                                   ^   ffff888976250180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb   ffff888976250200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb