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BUG: KASAN: use-after-free in __in_dev_get_rtnl include/linux/inetdevice.h:236 [inline]
BUG: KASAN: use-after-free in inet_gifconf+0x47e/0x490 net/ipv4/devinet.c:1243
Read of size 8 at addr ffff88805a43e318 by task syz-executor.3/20053

CPU: 1 PID: 20053 Comm: syz-executor.3 Not tainted 5.6.0-rc2-syzkaller #0
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+0x197/0x210 lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374
 __kasan_report.cold+0x1b/0x32 mm/kasan/report.c:506
 kasan_report+0x12/0x20 mm/kasan/common.c:641
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:135
 __in_dev_get_rtnl include/linux/inetdevice.h:236 [inline]
 inet_gifconf+0x47e/0x490 net/ipv4/devinet.c:1243
 dev_ifconf+0xd0/0x230 net/core/dev_ioctl.c:80
 sock_do_ioctl+0x260/0x2f0 net/socket.c:1067
 sock_ioctl+0x3ed/0x790 net/socket.c:1204
 vfs_ioctl fs/ioctl.c:47 [inline]
 ksys_ioctl+0x123/0x180 fs/ioctl.c:763
 __do_sys_ioctl fs/ioctl.c:772 [inline]
 __se_sys_ioctl fs/ioctl.c:770 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:770
 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45c6c9
Code: ad b6 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 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fa6f5232c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fa6f52336d4 RCX: 000000000045c6c9
RDX: 0000000000400200 RSI: 0000000000008912 RDI: 0000000000000006
RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 000000000000040e R14: 00000000004c698c R15: 000000000076bf2c

Allocated by task 2802:
 save_stack+0x23/0x90 mm/kasan/common.c:72
 set_track mm/kasan/common.c:80 [inline]
 __kasan_kmalloc mm/kasan/common.c:515 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:488
 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:529
 __do_kmalloc_node mm/slab.c:3616 [inline]
 __kmalloc_node_track_caller+0x4e/0x70 mm/slab.c:3630
 __kmalloc_reserve.isra.0+0x40/0xf0 net/core/skbuff.c:142
 __alloc_skb+0x10b/0x5e0 net/core/skbuff.c:210
 alloc_skb include/linux/skbuff.h:1051 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:324 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:376 [inline]
 nsim_dev_trap_report_work+0x25c/0xaf0 drivers/net/netdevsim/dev.c:415
 process_one_work+0xa05/0x17a0 kernel/workqueue.c:2264
 worker_thread+0x98/0xe40 kernel/workqueue.c:2410
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

Freed by task 2802:
 save_stack+0x23/0x90 mm/kasan/common.c:72
 set_track mm/kasan/common.c:80 [inline]
 kasan_set_free_info mm/kasan/common.c:337 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:476
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:485
 __cache_free mm/slab.c:3426 [inline]
 kfree+0x10a/0x2c0 mm/slab.c:3757
 skb_free_head+0x93/0xb0 net/core/skbuff.c:592
 skb_release_data+0x43c/0x8b0 net/core/skbuff.c:612
 skb_release_all+0x4d/0x60 net/core/skbuff.c:666
 __kfree_skb net/core/skbuff.c:680 [inline]
 consume_skb net/core/skbuff.c:839 [inline]
 consume_skb+0xfb/0x410 net/core/skbuff.c:833
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:390 [inline]
 nsim_dev_trap_report_work+0x7cb/0xaf0 drivers/net/netdevsim/dev.c:415
 process_one_work+0xa05/0x17a0 kernel/workqueue.c:2264
 worker_thread+0x98/0xe40 kernel/workqueue.c:2410
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

The buggy address belongs to the object at ffff88805a43e000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 792 bytes inside of
 4096-byte region [ffff88805a43e000, ffff88805a43f000)
The buggy address belongs to the page:
page:ffffea0001690f80 refcount:1 mapcount:0 mapping:ffff8880aa402000 index:0x0 compound_mapcount: 0
flags: 0xfffe0000010200(slab|head)
raw: 00fffe0000010200 ffffea0001625e88 ffffea0001379788 ffff8880aa402000
raw: 0000000000000000 ffff88805a43e000 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88805a43e200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805a43e280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88805a43e300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff88805a43e380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805a43e400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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