================================================================== BUG: KASAN: slab-out-of-bounds in tcp_retransmit_timer+0x6e9/0x1cb0 net/ipv4/tcp_timer.c:500 Read of size 8 at addr ffff888094a5a350 by task syz-executor.3/11021 CPU: 1 PID: 11021 Comm: syz-executor.3 Not tainted 5.9.0-rc8-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+0x1d6/0x29e lib/dump_stack.c:118 print_address_description+0x66/0x620 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report+0x132/0x1d0 mm/kasan/report.c:530 tcp_retransmit_timer+0x6e9/0x1cb0 net/ipv4/tcp_timer.c:500 tcp_write_timer_handler+0x1dc/0x8c0 net/ipv4/tcp_timer.c:611 tcp_write_timer+0x168/0x280 net/ipv4/tcp_timer.c:631 call_timer_fn+0x91/0x160 kernel/time/timer.c:1413 expire_timers kernel/time/timer.c:1458 [inline] __run_timers+0x65e/0x830 kernel/time/timer.c:1755 run_timer_softirq+0x46/0x80 kernel/time/timer.c:1768 __do_softirq+0x256/0x6d5 kernel/softirq.c:298 asm_call_irq_on_stack+0xf/0x20 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline] do_softirq_own_stack+0x8f/0xe0 arch/x86/kernel/irq_64.c:77 do_softirq+0x102/0x150 kernel/softirq.c:343 __local_bh_enable_ip+0x17f/0x1c0 kernel/softirq.c:195 get_next_corpse net/netfilter/nf_conntrack_core.c:2226 [inline] nf_ct_iterate_cleanup+0x307/0x390 net/netfilter/nf_conntrack_core.c:2249 nf_ct_iterate_cleanup_net+0xfc/0x150 net/netfilter/nf_conntrack_core.c:2334 masq_device_event+0x9b/0xd0 net/netfilter/nf_nat_masquerade.c:88 notifier_call_chain kernel/notifier.c:83 [inline] __raw_notifier_call_chain kernel/notifier.c:361 [inline] raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:368 __dev_notify_flags+0x253/0x4d0 net/core/dev.c:2033 dev_change_flags+0xe3/0x190 net/core/dev.c:8424 dev_ifsioc+0xc7/0xac0 net/core/dev_ioctl.c:265 dev_ioctl+0x4d1/0xc70 net/core/dev_ioctl.c:511 sock_do_ioctl+0x169/0x260 net/socket.c:1070 sock_ioctl+0x4aa/0x690 net/socket.c:1198 vfs_ioctl fs/ioctl.c:48 [inline] __do_sys_ioctl fs/ioctl.c:753 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:739 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45de29 Code: 0d b4 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 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f53c161bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000000133c0 RCX: 000000000045de29 RDX: 0000000020000340 RSI: 0000000000008914 RDI: 0000000000000005 RBP: 000000000118c008 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bfd4 R13: 00007ffc2528cc3f R14: 00007f53c161c9c0 R15: 000000000118bfd4 Allocated by task 10941: kasan_save_stack mm/kasan/common.c:48 [inline] kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc+0x100/0x130 mm/kasan/common.c:461 slab_post_alloc_hook+0x3e/0x290 mm/slab.h:518 slab_alloc mm/slab.c:3316 [inline] kmem_cache_alloc+0x1c1/0x2d0 mm/slab.c:3486 getname_flags+0xb8/0x610 fs/namei.c:138 user_path_at_empty+0x28/0x50 fs/namei.c:2646 user_path_at include/linux/namei.h:59 [inline] vfs_statx+0xb9/0x380 fs/stat.c:202 vfs_lstat include/linux/fs.h:3178 [inline] __do_sys_newlstat fs/stat.c:374 [inline] __se_sys_newlstat fs/stat.c:368 [inline] __x64_sys_newlstat+0x81/0xd0 fs/stat.c:368 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 10941: kasan_save_stack mm/kasan/common.c:48 [inline] kasan_set_track+0x3d/0x70 mm/kasan/common.c:56 kasan_set_free_info+0x17/0x30 mm/kasan/generic.c:355 __kasan_slab_free+0xdd/0x110 mm/kasan/common.c:422 __cache_free mm/slab.c:3422 [inline] kmem_cache_free+0x82/0xf0 mm/slab.c:3697 putname fs/namei.c:259 [inline] filename_lookup+0x410/0x5d0 fs/namei.c:2376 user_path_at include/linux/namei.h:59 [inline] vfs_statx+0xb9/0x380 fs/stat.c:202 vfs_lstat include/linux/fs.h:3178 [inline] __do_sys_newlstat fs/stat.c:374 [inline] __se_sys_newlstat fs/stat.c:368 [inline] __x64_sys_newlstat+0x81/0xd0 fs/stat.c:368 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff888094a5ae00 which belongs to the cache names_cache of size 4096 The buggy address is located 2736 bytes to the left of 4096-byte region [ffff888094a5ae00, ffff888094a5be00) The buggy address belongs to the page: page:00000000644f8c62 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x94a5a head:00000000644f8c62 order:1 compound_mapcount:0 flags: 0xfffe0000010200(slab|head) raw: 00fffe0000010200 ffffea0001556308 ffffea00011e0388 ffff8880aa624d00 raw: 0000000000000000 ffff888094a5ae00 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888094a5a200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888094a5a280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888094a5a300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888094a5a380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888094a5a400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================