================================================================== BUG: KASAN: slab-out-of-bounds in tcp_probe_timer net/ipv4/tcp_timer.c:372 [inline] BUG: KASAN: slab-out-of-bounds in tcp_write_timer_handler+0x9d0/0xa60 net/ipv4/tcp_timer.c:615 Read of size 4 at addr ffff88804b3ce77c by task syz-executor.0/26080 CPU: 0 PID: 26080 Comm: syz-executor.0 Not tainted 5.8.0-rc4-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+0x18f/0x20d lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xae/0x436 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530 tcp_probe_timer net/ipv4/tcp_timer.c:372 [inline] tcp_write_timer_handler+0x9d0/0xa60 net/ipv4/tcp_timer.c:615 tcp_write_timer+0xa2/0x2b0 net/ipv4/tcp_timer.c:631 call_timer_fn+0x1ac/0x760 kernel/time/timer.c:1404 expire_timers kernel/time/timer.c:1449 [inline] __run_timers.part.0+0x54c/0xa20 kernel/time/timer.c:1773 __run_timers kernel/time/timer.c:1745 [inline] run_timer_softirq+0xae/0x1a0 kernel/time/timer.c:1786 __do_softirq+0x34c/0xa60 kernel/softirq.c:292 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:711 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline] do_softirq_own_stack+0x111/0x170 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:387 [inline] __irq_exit_rcu kernel/softirq.c:417 [inline] irq_exit_rcu+0x229/0x270 kernel/softirq.c:429 sysvec_apic_timer_interrupt+0x54/0x120 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:587 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:765 [inline] RIP: 0010:lock_acquire+0x270/0xad0 kernel/locking/lockdep.c:4962 Code: 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 f8 06 00 00 48 83 3d bd df 5a 08 00 0f 84 a6 05 00 00 48 8b 7c 24 08 57 9d <0f> 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 48 03 44 24 10 48 c7 RSP: 0018:ffffc90003dafca0 EFLAGS: 00000282 RAX: 1ffffffff1369c10 RBX: ffff888095f9c440 RCX: 0000000000000001 RDX: dffffc0000000000 RSI: 0000000000000008 RDI: 0000000000000282 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8c5a5a77 R10: fffffbfff18b4b4e R11: 0000000000000000 R12: 0000000000000000 R13: ffff888053584210 R14: 0000000000000000 R15: ffff888095f9c440 down_write+0x8d/0x150 kernel/locking/rwsem.c:1531 inode_lock include/linux/fs.h:800 [inline] __sock_release+0x86/0x280 net/socket.c:595 sock_close+0x18/0x20 net/socket.c:1277 __fput+0x33c/0x880 fs/file_table.c:281 task_work_run+0xdd/0x190 kernel/task_work.c:135 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop arch/x86/entry/common.c:239 [inline] __prepare_exit_to_usermode+0x1e9/0x1f0 arch/x86/entry/common.c:269 do_syscall_64+0x6c/0xe0 arch/x86/entry/common.c:393 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x415d30 Code: Bad RIP value. RSP: 002b:00007ffc0a81b878 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 00007ffc0a81b980 RCX: 0000000000415d30 RDX: 00000000000000e0 RSI: 00007ffc0a81bd60 RDI: 0000000000000003 RBP: 0000000000000003 R08: 0000000000006000 R09: 0000000000004000 R10: 00007ffc0a81b980 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc0a81c000 R14: 00000000002a6529 R15: 00007ffc0a81c010 Allocated by task 21097: save_stack+0x1b/0x40 mm/kasan/common.c:48 set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xc2/0xd0 mm/kasan/common.c:494 slab_post_alloc_hook mm/slab.h:586 [inline] slab_alloc mm/slab.c:3320 [inline] kmem_cache_alloc+0x12c/0x3b0 mm/slab.c:3484 getname_flags.part.0+0x50/0x4f0 fs/namei.c:138 getname_flags fs/namei.c:2646 [inline] user_path_at_empty+0xa1/0x100 fs/namei.c:2646 user_path_at include/linux/namei.h:59 [inline] inotify_find_inode+0x2e/0x110 fs/notify/inotify/inotify_user.c:340 __do_sys_inotify_add_watch fs/notify/inotify/inotify_user.c:745 [inline] __se_sys_inotify_add_watch fs/notify/inotify/inotify_user.c:698 [inline] __x64_sys_inotify_add_watch+0x1f1/0x350 fs/notify/inotify/inotify_user.c:698 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 21097: save_stack+0x1b/0x40 mm/kasan/common.c:48 set_track mm/kasan/common.c:56 [inline] kasan_set_free_info mm/kasan/common.c:316 [inline] __kasan_slab_free+0xf5/0x140 mm/kasan/common.c:455 __cache_free mm/slab.c:3426 [inline] kmem_cache_free+0x7f/0x310 mm/slab.c:3694 putname+0xe1/0x120 fs/namei.c:259 filename_lookup+0x3b1/0x560 fs/namei.c:2376 user_path_at include/linux/namei.h:59 [inline] inotify_find_inode+0x2e/0x110 fs/notify/inotify/inotify_user.c:340 __do_sys_inotify_add_watch fs/notify/inotify/inotify_user.c:745 [inline] __se_sys_inotify_add_watch fs/notify/inotify/inotify_user.c:698 [inline] __x64_sys_inotify_add_watch+0x1f1/0x350 fs/notify/inotify/inotify_user.c:698 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff88804b3ced40 which belongs to the cache names_cache of size 4096 The buggy address is located 1476 bytes to the left of 4096-byte region [ffff88804b3ced40, ffff88804b3cfd40) The buggy address belongs to the page: page:ffffea00012cf380 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 head:ffffea00012cf380 order:1 compound_mapcount:0 flags: 0xfffe0000010200(slab|head) raw: 00fffe0000010200 ffffea00013ea988 ffffea00015e7888 ffff8880aa1d0000 raw: 0000000000000000 ffff88804b3ced40 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88804b3ce600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88804b3ce680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88804b3ce700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88804b3ce780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88804b3ce800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================