bisecting fixing commit since 7fd2bf83d59a2d32e0d596c5d3e623b9a0e7e2d5 building syzkaller on 838e7e2cd9228583ca33c49a39aea4d863d3e36d testing commit 7fd2bf83d59a2d32e0d596c5d3e623b9a0e7e2d5 compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: 01b893fbad8e791d37845f483396b9f7db77ffec1671a35635c59f9e3974f70b run #0: crashed: KASAN: use-after-free Read in sk_psock_backlog run #1: crashed: KASAN: use-after-free Read in consume_skb run #2: crashed: KASAN: use-after-free Read in consume_skb run #3: crashed: KASAN: use-after-free Read in consume_skb run #4: crashed: KASAN: use-after-free Read in consume_skb run #5: crashed: KASAN: use-after-free Read in consume_skb run #6: crashed: KASAN: use-after-free Read in sk_psock_backlog run #7: crashed: KASAN: use-after-free Read in consume_skb run #8: crashed: KASAN: use-after-free Read in consume_skb run #9: crashed: KASAN: use-after-free Read in consume_skb run #10: crashed: KASAN: use-after-free Read in consume_skb run #11: crashed: KASAN: use-after-free Read in consume_skb run #12: crashed: KASAN: use-after-free Read in consume_skb run #13: crashed: KASAN: use-after-free Read in consume_skb run #14: crashed: KASAN: use-after-free Read in consume_skb run #15: crashed: KASAN: use-after-free Read in consume_skb run #16: crashed: KASAN: use-after-free Read in consume_skb run #17: crashed: KASAN: use-after-free Read in consume_skb run #18: crashed: KASAN: use-after-free Read in consume_skb run #19: crashed: KASAN: use-after-free Read in consume_skb testing current HEAD 9b59ec8d50a1f28747ceff9a4f39af5deba9540e testing commit 9b59ec8d50a1f28747ceff9a4f39af5deba9540e compiler: gcc (GCC) 10.2.1 20210217, GNU ld (GNU Binutils for Debian) 2.35.2 kernel signature: b6716ac8aa035c94b563a0c4407c3be392dc947c6876a8e69f73f5af7abb37a4 all runs: crashed: KASAN: use-after-free Read in consume_skb revisions tested: 2, total time: 20m35.353291578s (build: 13m19.704618265s, test: 6m24.900349759s) the crash still happens on HEAD commit msg: Merge tag 'riscv-for-linus-5.19-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux crash: KASAN: use-after-free Read in consume_skb IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready IPv6: ADDRCONF(NETDEV_CHANGE): wlan1: link becomes ready ================================================================== BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:71 [inline] BUG: KASAN: use-after-free in atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] BUG: KASAN: use-after-free in refcount_read include/linux/refcount.h:147 [inline] BUG: KASAN: use-after-free in skb_unref include/linux/skbuff.h:1359 [inline] BUG: KASAN: use-after-free in consume_skb+0x23/0xf0 net/core/skbuff.c:913 Read of size 4 at addr ffff88806f0bcadc by task kworker/1:3/3650 CPU: 1 PID: 3650 Comm: kworker/1:3 Not tainted 5.19.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022 Workqueue: events bpf_map_free_deferred Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x57/0x7d lib/dump_stack.c:106 print_address_description.constprop.0.cold+0xeb/0x495 mm/kasan/report.c:313 print_report mm/kasan/report.c:429 [inline] kasan_report.cold+0xf4/0x1c6 mm/kasan/report.c:491 check_region_inline mm/kasan/generic.c:183 [inline] kasan_check_range+0x13d/0x180 mm/kasan/generic.c:189 instrument_atomic_read include/linux/instrumented.h:71 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] refcount_read include/linux/refcount.h:147 [inline] skb_unref include/linux/skbuff.h:1359 [inline] consume_skb+0x23/0xf0 net/core/skbuff.c:913 __sk_msg_free+0x198/0x340 net/core/skmsg.c:205 sk_msg_free net/core/skmsg.c:218 [inline] __sk_psock_purge_ingress_msg net/core/skmsg.c:766 [inline] __sk_psock_zap_ingress net/core/skmsg.c:784 [inline] sk_psock_stop+0x3f3/0x640 net/core/skmsg.c:802 sk_psock_drop+0x14f/0x350 net/core/skmsg.c:844 sk_psock_put include/linux/skmsg.h:450 [inline] sock_map_unref net/core/sock_map.c:185 [inline] sock_hash_free+0x53f/0x730 net/core/sock_map.c:1150 process_one_work+0x865/0x13d0 kernel/workqueue.c:2289 worker_thread+0x598/0xec0 kernel/workqueue.c:2436 kthread+0x299/0x340 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Allocated by task 4151: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:436 [inline] __kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:469 kasan_slab_alloc include/linux/kasan.h:224 [inline] slab_post_alloc_hook mm/slab.h:750 [inline] slab_alloc_node mm/slub.c:3243 [inline] slab_alloc mm/slub.c:3251 [inline] __kmem_cache_alloc_lru mm/slub.c:3258 [inline] kmem_cache_alloc+0x204/0x3b0 mm/slub.c:3268 skb_clone+0x11c/0x2f0 net/core/skbuff.c:1515 sk_psock_verdict_recv+0x48/0x610 net/core/skmsg.c:1177 unix_read_sock+0xc4/0x1e0 net/unix/af_unix.c:2506 sk_psock_verdict_data_ready+0xf8/0x150 net/core/skmsg.c:1220 unix_dgram_sendmsg+0xcc5/0x1790 net/unix/af_unix.c:2028 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xab/0xe0 net/socket.c:734 ____sys_sendmsg+0x395/0x7a0 net/socket.c:2488 ___sys_sendmsg+0xd3/0x150 net/socket.c:2542 __sys_sendmmsg+0x141/0x310 net/socket.c:2628 __do_sys_sendmmsg net/socket.c:2657 [inline] __se_sys_sendmmsg net/socket.c:2654 [inline] __x64_sys_sendmmsg+0x94/0x100 net/socket.c:2654 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0x80 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 3652: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free+0x166/0x1a0 mm/kasan/common.c:328 kasan_slab_free include/linux/kasan.h:200 [inline] slab_free_hook mm/slub.c:1754 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1780 slab_free mm/slub.c:3536 [inline] kmem_cache_free+0xdd/0x5a0 mm/slub.c:3553 kfree_skb include/linux/skbuff.h:1375 [inline] sock_drop include/linux/skmsg.h:304 [inline] sk_psock_backlog+0x871/0xd20 net/core/skmsg.c:681 process_one_work+0x865/0x13d0 kernel/workqueue.c:2289 worker_thread+0x598/0xec0 kernel/workqueue.c:2436 kthread+0x299/0x340 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 The buggy address belongs to the object at ffff88806f0bca00 which belongs to the cache skbuff_head_cache of size 232 The buggy address is located 220 bytes inside of 232-byte region [ffff88806f0bca00, ffff88806f0bcae8) The buggy address belongs to the physical page: page:ffffea0001bc2f00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x6f0bc memcg:ffff888073abd981 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 0000000000000000 dead000000000122 ffff8880150c1140 raw: 0000000000000000 00000000000c000c 00000001ffffffff ffff888073abd981 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 4149, tgid 4148 (syz-executor.0), ts 88028313027, free_ts 59037553842 prep_new_page mm/page_alloc.c:2456 [inline] get_page_from_freelist+0x19d3/0x3b30 mm/page_alloc.c:4198 __alloc_pages+0x1c7/0x510 mm/page_alloc.c:5426 alloc_slab_page mm/slub.c:1824 [inline] allocate_slab+0x26c/0x3c0 mm/slub.c:1969 new_slab mm/slub.c:2029 [inline] ___slab_alloc+0x9bc/0xe10 mm/slub.c:3031 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3118 slab_alloc_node mm/slub.c:3209 [inline] kmem_cache_alloc_node+0x122/0x3f0 mm/slub.c:3293 __alloc_skb+0x151/0x270 net/core/skbuff.c:414 alloc_skb include/linux/skbuff.h:1426 [inline] alloc_skb_with_frags+0x73/0x6f0 net/core/skbuff.c:5992 sock_alloc_send_pskb+0x636/0x7c0 net/core/sock.c:2662 unix_dgram_sendmsg+0x36f/0x1790 net/unix/af_unix.c:1895 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xab/0xe0 net/socket.c:734 ____sys_sendmsg+0x395/0x7a0 net/socket.c:2488 ___sys_sendmsg+0xd3/0x150 net/socket.c:2542 __sys_sendmmsg+0x141/0x310 net/socket.c:2628 __do_sys_sendmmsg net/socket.c:2657 [inline] __se_sys_sendmmsg net/socket.c:2654 [inline] __x64_sys_sendmmsg+0x94/0x100 net/socket.c:2654 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0x80 arch/x86/entry/common.c:80 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1371 [inline] free_pcp_prepare+0x549/0xd20 mm/page_alloc.c:1421 free_unref_page_prepare mm/page_alloc.c:3343 [inline] free_unref_page+0x19/0x6a0 mm/page_alloc.c:3438 __vunmap+0x66d/0xb40 mm/vmalloc.c:2665 free_work+0x4b/0x70 mm/vmalloc.c:97 process_one_work+0x865/0x13d0 kernel/workqueue.c:2289 worker_thread+0x598/0xec0 kernel/workqueue.c:2436 kthread+0x299/0x340 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Memory state around the buggy address: ffff88806f0bc980: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc ffff88806f0bca00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88806f0bca80: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc ^ ffff88806f0bcb00: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ffff88806f0bcb80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================