================================================================== 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 ffff888095bce67c by task syz-executor.4/28565 CPU: 1 PID: 28565 Comm: syz-executor.4 Not tainted 5.9.0-rc1-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/0x497 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:1413 expire_timers kernel/time/timer.c:1458 [inline] __run_timers.part.0+0x67c/0xaa0 kernel/time/timer.c:1755 __run_timers kernel/time/timer.c:1736 [inline] run_timer_softirq+0xae/0x1a0 kernel/time/timer.c:1768 __do_softirq+0x2de/0xa24 kernel/softirq.c:298 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706 __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+0x9d/0xd0 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:393 [inline] __irq_exit_rcu kernel/softirq.c:423 [inline] irq_exit_rcu+0x1f3/0x230 kernel/softirq.c:435 sysvec_apic_timer_interrupt+0x51/0xf0 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:770 [inline] RIP: 0010:kmem_cache_free.part.0+0x8c/0x1f0 mm/slab.c:3694 Code: e8 89 25 00 00 84 c0 74 76 41 f7 c4 00 02 00 00 74 4e e8 e7 f7 c5 ff 48 83 3d c7 25 02 08 00 0f 84 2f 01 00 00 4c 89 e7 57 9d <0f> 1f 44 00 00 4c 8b 64 24 20 0f 1f 44 00 00 65 8b 05 fe 82 4d 7e RSP: 0018:ffffc900057f7958 EFLAGS: 00000282 RAX: 00000000000007a9 RBX: ffff88808b879cb0 RCX: 1ffffffff1563c69 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000282 RBP: ffff88821bc47300 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000282 R13: ffffffff81a954e2 R14: ffff88809bed4b08 R15: 0000000000000001 anon_vma_chain_free mm/rmap.c:141 [inline] unlink_anon_vmas+0x462/0x830 mm/rmap.c:432 free_pgtables+0xe2/0x2f0 mm/memory.c:400 exit_mmap+0x2c0/0x530 mm/mmap.c:3184 __mmput+0x122/0x470 kernel/fork.c:1076 mmput+0x53/0x60 kernel/fork.c:1097 exit_mm kernel/exit.c:483 [inline] do_exit+0xa8b/0x29f0 kernel/exit.c:793 do_group_exit+0x125/0x310 kernel/exit.c:903 get_signal+0x428/0x1f00 kernel/signal.c:2757 arch_do_signal+0x82/0x2520 arch/x86/kernel/signal.c:811 exit_to_user_mode_loop kernel/entry/common.c:135 [inline] exit_to_user_mode_prepare+0x15d/0x1c0 kernel/entry/common.c:166 syscall_exit_to_user_mode+0x59/0x2b0 kernel/entry/common.c:241 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45d4d9 Code: Bad RIP value. RSP: 002b:00007f4545a0dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: 0000000000043400 RBX: 0000000000038c80 RCX: 000000000045d4d9 RDX: 0000000000043400 RSI: 0000000020000200 RDI: 0000000000000006 RBP: 000000000118d160 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118d12c R13: 00007ffe712fcb2f R14: 00007f4545a0e9c0 R15: 000000000118d12c Allocated by task 28501: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:461 slab_post_alloc_hook mm/slab.h:518 [inline] slab_alloc mm/slab.c:3312 [inline] kmem_cache_alloc+0x138/0x3a0 mm/slab.c:3482 getname_flags.part.0+0x50/0x4f0 fs/namei.c:138 getname_flags+0x9a/0xe0 include/linux/audit.h:320 getname fs/namei.c:209 [inline] do_symlinkat+0x86/0x2c0 fs/namei.c:3975 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 28501: kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48 kasan_set_track+0x1c/0x30 mm/kasan/common.c:56 kasan_set_free_info+0x1b/0x30 mm/kasan/generic.c:355 __kasan_slab_free+0xd8/0x120 mm/kasan/common.c:422 __cache_free mm/slab.c:3418 [inline] kmem_cache_free.part.0+0x67/0x1f0 mm/slab.c:3693 putname+0xe1/0x120 fs/namei.c:259 do_symlinkat+0x1b2/0x2c0 fs/namei.c:3993 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The buggy address belongs to the object at ffff888095bce940 which belongs to the cache names_cache of size 4096 The buggy address is located 708 bytes to the left of 4096-byte region [ffff888095bce940, ffff888095bcf940) The buggy address belongs to the page: page:000000005394af1d refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x95bce head:000000005394af1d order:1 compound_mapcount:0 flags: 0xfffe0000010200(slab|head) raw: 00fffe0000010200 ffffea0001a8cd08 ffffea00023b2708 ffff88821bc47a00 raw: 0000000000000000 ffff888095bce940 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888095bce500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888095bce580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888095bce600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888095bce680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888095bce700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================