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BUG: KASAN: slab-out-of-bounds in pskb_may_pull include/linux/skbuff.h:2106 [inline]
BUG: KASAN: slab-out-of-bounds in skb_ensure_writable+0x554/0x620 net/core/skbuff.c:5118
Read of size 4 at addr ffff8801c481c040 by task syz-executor6/6697

CPU: 0 PID: 6697 Comm: syz-executor6 Not tainted 4.17.0+ #94
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+0x1b9/0x294 lib/dump_stack.c:113
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report.c:432
 pskb_may_pull include/linux/skbuff.h:2106 [inline]
 skb_ensure_writable+0x554/0x620 net/core/skbuff.c:5118
 __bpf_try_make_writable net/core/filter.c:1606 [inline]
 bpf_try_make_writable net/core/filter.c:1612 [inline]
 ____bpf_l4_csum_replace net/core/filter.c:1822 [inline]
 bpf_l4_csum_replace+0x91/0x4a0 net/core/filter.c:1809
XFS (loop5): unknown mount option [noľ].

Allocated by task 2414:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553
 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490
 kmem_cache_alloc+0x12e/0x760 mm/slab.c:3554
 skb_clone+0x1ed/0x4f0 net/core/skbuff.c:1282
 do_one_broadcast net/netlink/af_netlink.c:1435 [inline]
 netlink_broadcast_filtered+0x1024/0x1580 net/netlink/af_netlink.c:1510
 netlink_broadcast+0x3a/0x50 net/netlink/af_netlink.c:1534
 uevent_net_broadcast_untagged lib/kobject_uevent.c:329 [inline]
 kobject_uevent_net_broadcast lib/kobject_uevent.c:406 [inline]
 kobject_uevent_env+0x829/0x1110 lib/kobject_uevent.c:587
 kobject_synth_uevent+0xa4f/0xc0b lib/kobject_uevent.c:208
 uevent_store+0x26/0x70 drivers/base/core.c:1013
 dev_attr_store+0x5e/0x90 drivers/base/core.c:733
 sysfs_kf_write+0x118/0x170 fs/sysfs/file.c:139
 kernfs_fop_write+0x2ba/0x480 fs/kernfs/file.c:316
 __vfs_write+0x10b/0x9d0 fs/read_write.c:485
 vfs_write+0x1f8/0x560 fs/read_write.c:549
 ksys_write+0xf9/0x250 fs/read_write.c:598
 __do_sys_write fs/read_write.c:610 [inline]
 __se_sys_write fs/read_write.c:607 [inline]
 __x64_sys_write+0x73/0xb0 fs/read_write.c:607
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 2414:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3498 [inline]
 kmem_cache_free+0x86/0x2d0 mm/slab.c:3756
 kfree_skbmem+0x13c/0x210 net/core/skbuff.c:582
 __kfree_skb net/core/skbuff.c:642 [inline]
 consume_skb+0x193/0x550 net/core/skbuff.c:701
 skb_free_datagram+0x1a/0xf0 net/core/datagram.c:329
 netlink_recvmsg+0x6fe/0x1450 net/netlink/af_netlink.c:1980
 sock_recvmsg_nosec net/socket.c:806 [inline]
 sock_recvmsg+0xd0/0x110 net/socket.c:813
 ___sys_recvmsg+0x2b6/0x680 net/socket.c:2311
 __sys_recvmsg+0x112/0x260 net/socket.c:2360
 __do_sys_recvmsg net/socket.c:2370 [inline]
 __se_sys_recvmsg net/socket.c:2367 [inline]
 __x64_sys_recvmsg+0x78/0xb0 net/socket.c:2367
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8801c481c080
 which belongs to the cache skbuff_head_cache of size 232
The buggy address is located 64 bytes to the left of
 232-byte region [ffff8801c481c080, ffff8801c481c168)
The buggy address belongs to the page:
page:ffffea0007120700 count:1 mapcount:0 mapping:ffff8801d9a0d080 index:0xffff8801c481cbc0
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffffea0006c2a588 ffffea000740f9c8 ffff8801d9a0d080
raw: ffff8801c481cbc0 ffff8801c481c080 000000010000000b 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801c481bf00: fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801c481bf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8801c481c000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                           ^
 ffff8801c481c080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801c481c100: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc
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