================================================================== BUG: KASAN: use-after-free in atomic_read include/asm-generic/atomic-instrumented.h:26 [inline] BUG: KASAN: use-after-free in atomic_fetch_add_unless include/linux/atomic-fallback.h:1086 [inline] BUG: KASAN: use-after-free in atomic_add_unless include/linux/atomic-fallback.h:1111 [inline] BUG: KASAN: use-after-free in atomic_inc_not_zero include/linux/atomic-fallback.h:1127 [inline] BUG: KASAN: use-after-free in dst_hold_safe include/net/dst.h:297 [inline] BUG: KASAN: use-after-free in ip6_hold_safe+0xad/0x380 net/ipv6/route.c:1166 Read of size 4 at addr ffff88809574a450 by task syz-executor.0/30850 CPU: 1 PID: 30850 Comm: syz-executor.0 Not tainted 5.2.0-rc3+ #28 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:188 __kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 kasan_report+0x12/0x20 mm/kasan/common.c:614 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x123/0x190 mm/kasan/generic.c:191 kasan_check_read+0x11/0x20 mm/kasan/common.c:94 atomic_read include/asm-generic/atomic-instrumented.h:26 [inline] atomic_fetch_add_unless include/linux/atomic-fallback.h:1086 [inline] atomic_add_unless include/linux/atomic-fallback.h:1111 [inline] atomic_inc_not_zero include/linux/atomic-fallback.h:1127 [inline] dst_hold_safe include/net/dst.h:297 [inline] ip6_hold_safe+0xad/0x380 net/ipv6/route.c:1166 rt6_get_pcpu_route net/ipv6/route.c:1395 [inline] ip6_pol_route+0x2e9/0xe40 net/ipv6/route.c:2251 ip6_pol_route_output+0x54/0x70 net/ipv6/route.c:2427 fib6_rule_lookup+0x133/0x5a0 net/ipv6/fib6_rules.c:116 ip6_route_output_flags+0x2c4/0x350 net/ipv6/route.c:2456 ip6_route_output include/net/ip6_route.h:93 [inline] ip6_dst_lookup_tail+0xd1f/0x1f90 net/ipv6/ip6_output.c:1022 ip6_dst_lookup_flow+0xa8/0x220 net/ipv6/ip6_output.c:1150 sctp_v6_get_dst+0x785/0x1ce0 net/sctp/ipv6.c:278 sctp_transport_route+0x12d/0x360 net/sctp/transport.c:297 sctp_assoc_add_peer+0x53e/0xfc0 net/sctp/associola.c:663 sctp_process_param net/sctp/sm_make_chunk.c:2522 [inline] sctp_process_init+0x2458/0x2ad0 net/sctp/sm_make_chunk.c:2343 sctp_sf_do_unexpected_init net/sctp/sm_statefuns.c:1541 [inline] sctp_sf_do_unexpected_init.isra.0+0x7cd/0x1350 net/sctp/sm_statefuns.c:1441 sctp_sf_do_5_2_1_siminit+0x35/0x40 net/sctp/sm_statefuns.c:1670 sctp_do_sm+0x121/0x5190 net/sctp/sm_sideeffect.c:1152 sctp_assoc_bh_rcv+0x343/0x660 net/sctp/associola.c:1059 sctp_inq_push+0x1e4/0x280 net/sctp/inqueue.c:80 sctp_backlog_rcv+0x196/0xbe0 net/sctp/input.c:339 sk_backlog_rcv include/net/sock.h:945 [inline] __release_sock+0x129/0x390 net/core/sock.c:2412 release_sock+0x59/0x1c0 net/core/sock.c:2928 sctp_wait_for_connect+0x316/0x540 net/sctp/socket.c:9039 __sctp_connect+0xab2/0xcd0 net/sctp/socket.c:1226 sctp_connect net/sctp/socket.c:4846 [inline] sctp_inet_connect+0x29c/0x340 net/sctp/socket.c:4862 __sys_connect+0x264/0x330 net/socket.c:1834 __do_sys_connect net/socket.c:1845 [inline] __se_sys_connect net/socket.c:1842 [inline] __x64_sys_connect+0x73/0xb0 net/socket.c:1842 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4592c9 Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007efc1bd81c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004592c9 RDX: 000000000000001c RSI: 0000000020000080 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007efc1bd826d4 R13: 00000000004bf7b5 R14: 00000000004d0f38 R15: 00000000ffffffff Allocated by task 30429: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_kmalloc mm/kasan/common.c:489 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:462 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:497 slab_post_alloc_hook mm/slab.h:437 [inline] slab_alloc mm/slab.c:3326 [inline] kmem_cache_alloc+0x11a/0x6f0 mm/slab.c:3488 kmem_cache_zalloc include/linux/slab.h:732 [inline] __alloc_file+0x27/0x300 fs/file_table.c:101 alloc_empty_file+0x72/0x170 fs/file_table.c:151 path_openat+0xef/0x46d0 fs/namei.c:3522 do_filp_open+0x1a1/0x280 fs/namei.c:3563 do_sys_open+0x3fe/0x5d0 fs/open.c:1070 __do_sys_open fs/open.c:1088 [inline] __se_sys_open fs/open.c:1083 [inline] __x64_sys_open+0x7e/0xc0 fs/open.c:1083 do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 9: save_stack+0x23/0x90 mm/kasan/common.c:71 set_track mm/kasan/common.c:79 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:451 kasan_slab_free+0xe/0x10 mm/kasan/common.c:459 __cache_free mm/slab.c:3432 [inline] kmem_cache_free+0x86/0x260 mm/slab.c:3698 file_free_rcu+0x98/0xe0 fs/file_table.c:50 __rcu_reclaim kernel/rcu/rcu.h:222 [inline] rcu_do_batch kernel/rcu/tree.c:2092 [inline] invoke_rcu_callbacks kernel/rcu/tree.c:2310 [inline] rcu_core+0xba5/0x1500 kernel/rcu/tree.c:2291 __do_softirq+0x25c/0x94c kernel/softirq.c:293 The buggy address belongs to the object at ffff88809574a300 which belongs to the cache filp of size 456 The buggy address is located 336 bytes inside of 456-byte region [ffff88809574a300, ffff88809574a4c8) The buggy address belongs to the page: page:ffffea000255d280 refcount:1 mapcount:0 mapping:ffff88821bc48380 index:0xffff88809574aa80 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea00021860c8 ffffea00024c0ec8 ffff88821bc48380 raw: ffff88809574aa80 ffff88809574a080 0000000100000004 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809574a300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88809574a380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88809574a400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88809574a480: fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc ffff88809574a500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================