================================================================== BUG: KASAN: use-after-free in __read_once_size /./include/linux/compiler.h:248 [inline] BUG: KASAN: use-after-free in atomic_read /./arch/x86/include/asm/atomic.h:26 [inline] BUG: KASAN: use-after-free in __atomic_add_unless /./arch/x86/include/asm/atomic.h:240 [inline] BUG: KASAN: use-after-free in atomic_add_unless /./include/linux/atomic.h:506 [inline] BUG: KASAN: use-after-free in sk_dst_get /./include/net/sock.h:1706 [inline] BUG: KASAN: use-after-free in sk_dst_check+0x347/0x380 /net/core/sock.c:513 Read of size 4 at addr ffff880131a38580 by task syz-executor.4/29950 CPU: 1 PID: 29950 Comm: syz-executor.4 Not tainted 4.9.186+ #9 ffff8801380e76c8 ffffffff81b5a0b1 0000000000000000 ffffea0004c68e00 ffff880131a38580 0000000000000004 ffffffff822c2cf7 ffff8801380e7700 ffffffff8150ab68 0000000000000000 ffff880131a38580 ffff880131a38580 Call Trace: [<00000000f44aabf4>] __dump_stack /lib/dump_stack.c:15 [inline] [<00000000f44aabf4>] dump_stack+0xc1/0x120 /lib/dump_stack.c:51 [<0000000059158811>] print_address_description+0x6f/0x23a /mm/kasan/report.c:256 [<00000000b8c4ec60>] kasan_report_error /mm/kasan/report.c:355 [inline] [<00000000b8c4ec60>] kasan_report /mm/kasan/report.c:413 [inline] [<00000000b8c4ec60>] kasan_report.cold+0x8c/0x2ba /mm/kasan/report.c:397 [<00000000e33568cc>] __asan_report_load4_noabort+0x14/0x20 /mm/kasan/report.c:433 [<00000000ad071f96>] __read_once_size /./include/linux/compiler.h:248 [inline] [<00000000ad071f96>] atomic_read /./arch/x86/include/asm/atomic.h:26 [inline] [<00000000ad071f96>] __atomic_add_unless /./arch/x86/include/asm/atomic.h:240 [inline] [<00000000ad071f96>] atomic_add_unless /./include/linux/atomic.h:506 [inline] [<00000000ad071f96>] sk_dst_get /./include/net/sock.h:1706 [inline] [<00000000ad071f96>] sk_dst_check+0x347/0x380 /net/core/sock.c:513 [<00000000eddee8b0>] udp_sendmsg+0x10a6/0x1c60 /net/ipv4/udp.c:1014 [<0000000008784924>] inet_sendmsg+0x202/0x4d0 /net/ipv4/af_inet.c:766 [<0000000061547115>] sock_sendmsg_nosec /net/socket.c:649 [inline] [<0000000061547115>] sock_sendmsg+0xbe/0x110 /net/socket.c:659 [<000000008cbe31a8>] ___sys_sendmsg+0x387/0x8b0 /net/socket.c:1983 [<000000007ae7fe22>] __sys_sendmmsg+0x164/0x3d0 /net/socket.c:2073 [<00000000401f42f9>] SYSC_sendmmsg /net/socket.c:2104 [inline] [<00000000401f42f9>] SyS_sendmmsg+0x35/0x60 /net/socket.c:2099 [<000000000c54ab60>] do_syscall_64+0x1ad/0x5c0 /arch/x86/entry/common.c:288 [<00000000677a2fcf>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb Allocated by task 29950: save_stack_trace+0x16/0x20 /arch/x86/kernel/stacktrace.c:57 save_stack /mm/kasan/kasan.c:512 [inline] set_track /mm/kasan/kasan.c:524 [inline] kasan_kmalloc.part.0+0x62/0xf0 /mm/kasan/kasan.c:616 kasan_kmalloc+0xb7/0xd0 /mm/kasan/kasan.c:601 kasan_slab_alloc+0xf/0x20 /mm/kasan/kasan.c:554 slab_post_alloc_hook /mm/slab.h:417 [inline] slab_alloc_node /mm/slub.c:2715 [inline] slab_alloc /mm/slub.c:2723 [inline] kmem_cache_alloc+0xd5/0x2b0 /mm/slub.c:2728 dst_alloc+0xf3/0x1b0 /net/core/dst.c:210 ipv4_blackhole_route+0x30/0x720 /net/ipv4/route.c:2442 make_blackhole /net/xfrm/xfrm_policy.c:2214 [inline] xfrm_lookup_route /net/xfrm/xfrm_policy.c:2387 [inline] xfrm_lookup_route+0xf4/0x140 /net/xfrm/xfrm_policy.c:2378 ip_route_output_flow+0x93/0xa0 /net/ipv4/route.c:2483 udp_sendmsg+0x1494/0x1c60 /net/ipv4/udp.c:1029 inet_sendmsg+0x202/0x4d0 /net/ipv4/af_inet.c:766 sock_sendmsg_nosec /net/socket.c:649 [inline] sock_sendmsg+0xbe/0x110 /net/socket.c:659 ___sys_sendmsg+0x387/0x8b0 /net/socket.c:1983 __sys_sendmmsg+0x164/0x3d0 /net/socket.c:2073 SYSC_sendmmsg /net/socket.c:2104 [inline] SyS_sendmmsg+0x35/0x60 /net/socket.c:2099 do_syscall_64+0x1ad/0x5c0 /arch/x86/entry/common.c:288 entry_SYSCALL_64_after_swapgs+0x5d/0xdb Freed by task 29415: save_stack_trace+0x16/0x20 /arch/x86/kernel/stacktrace.c:57 save_stack /mm/kasan/kasan.c:512 [inline] set_track /mm/kasan/kasan.c:524 [inline] kasan_slab_free+0xb0/0x190 /mm/kasan/kasan.c:589 slab_free_hook /mm/slub.c:1355 [inline] slab_free_freelist_hook /mm/slub.c:1377 [inline] slab_free /mm/slub.c:2958 [inline] kmem_cache_free+0xbe/0x310 /mm/slub.c:2980 dst_destroy+0x275/0x350 /net/core/dst.c:270 dst_gc_task+0x1b2/0x520 /net/core/dst.c:89 process_one_work+0x88b/0x1600 /kernel/workqueue.c:2114 worker_thread+0x5df/0x11d0 /kernel/workqueue.c:2251 kthread+0x278/0x310 /kernel/kthread.c:211 ret_from_fork+0x5c/0x70 /arch/x86/entry/entry_64.S:375 The buggy address belongs to the object at ffff880131a38500 which belongs to the cache ip_dst_cache of size 216 The buggy address is located 128 bytes inside of 216-byte region [ffff880131a38500, ffff880131a385d8) The buggy address belongs to the page: page:ffffea0004c68e00 count:1 mapcount:0 mapping: (null) index:0x0 flags: 0x4000000000000200(slab) page dumped because: kasan: bad access detected Memory state around the buggy address: ffff880131a38480: 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc ffff880131a38500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff880131a38580: fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc fc ^ ffff880131a38600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff880131a38680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== EXT4-fs warning (device sda1): verify_group_input:102: Cannot add at group 1 (only 16 groups)