================================================================== BUG: KASAN: use-after-free in ____bpf_clone_redirect net/core/filter.c:1768 [inline] BUG: KASAN: use-after-free in bpf_clone_redirect+0x2de/0x2f0 net/core/filter.c:1759 Read of size 8 at addr ffff888091e62250 by task syz-executor.3/16424 CPU: 0 PID: 16424 Comm: syz-executor.3 Not tainted 4.14.139 #35 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x138/0x19c lib/dump_stack.c:53 print_address_description.cold+0x7c/0x1dc mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report mm/kasan/report.c:409 [inline] kasan_report.cold+0xa9/0x2af mm/kasan/report.c:393 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:430 ____bpf_clone_redirect net/core/filter.c:1768 [inline] bpf_clone_redirect+0x2de/0x2f0 net/core/filter.c:1759 bpf_prog_71e1d56bce5f38ff+0x4c8/0x1000 Allocated by task 3527: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x45/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc mm/kasan/kasan.c:551 [inline] kasan_kmalloc+0xce/0xf0 mm/kasan/kasan.c:529 kasan_slab_alloc+0xf/0x20 mm/kasan/kasan.c:489 kmem_cache_alloc_node+0x144/0x780 mm/slab.c:3642 __alloc_skb+0x9c/0x500 net/core/skbuff.c:193 alloc_skb include/linux/skbuff.h:980 [inline] kobject_uevent_env+0x781/0xc23 lib/kobject_uevent.c:479 kobject_synth_uevent.cold+0x7d/0xcd lib/kobject_uevent.c:205 uevent_store+0x26/0x70 drivers/base/core.c:996 dev_attr_store+0x59/0x80 drivers/base/core.c:714 sysfs_kf_write+0x10c/0x160 fs/sysfs/file.c:141 kernfs_fop_write+0x291/0x450 fs/kernfs/file.c:316 __vfs_write+0x105/0x6b0 fs/read_write.c:480 vfs_write+0x198/0x500 fs/read_write.c:544 SYSC_write fs/read_write.c:590 [inline] SyS_write+0xfd/0x230 fs/read_write.c:582 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 Freed by task 3527: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x45/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x75/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3496 [inline] kmem_cache_free+0x83/0x2b0 mm/slab.c:3758 kfree_skbmem net/core/skbuff.c:586 [inline] kfree_skbmem+0xac/0x120 net/core/skbuff.c:580 __kfree_skb net/core/skbuff.c:646 [inline] consume_skb+0xb7/0x340 net/core/skbuff.c:705 netlink_broadcast_filtered+0x2ae/0x9f0 net/netlink/af_netlink.c:1488 kobject_uevent_env+0x8da/0xc23 lib/kobject_uevent.c:495 kobject_synth_uevent.cold+0x7d/0xcd lib/kobject_uevent.c:205 uevent_store+0x26/0x70 drivers/base/core.c:996 dev_attr_store+0x59/0x80 drivers/base/core.c:714 sysfs_kf_write+0x10c/0x160 fs/sysfs/file.c:141 kernfs_fop_write+0x291/0x450 fs/kernfs/file.c:316 __vfs_write+0x105/0x6b0 fs/read_write.c:480 vfs_write+0x198/0x500 fs/read_write.c:544 SYSC_write fs/read_write.c:590 [inline] SyS_write+0xfd/0x230 fs/read_write.c:582 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x42/0xb7 The buggy address belongs to the object at ffff888091e621c0 which belongs to the cache skbuff_head_cache of size 232 The buggy address is located 144 bytes inside of 232-byte region [ffff888091e621c0, ffff888091e622a8) The buggy address belongs to the page: page:ffffea0002479880 count:1 mapcount:0 mapping:ffff888091e62080 index:0xffff888091e62a80 flags: 0x1fffc0000000100(slab) raw: 01fffc0000000100 ffff888091e62080 ffff888091e62a80 0000000100000009 raw: ffffea000243e720 ffffea0002a6b220 ffff88821b719240 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888091e62100: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc ffff888091e62180: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb >ffff888091e62200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888091e62280: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc ffff888091e62300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================