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BUG: KASAN: slab-out-of-bounds in tcp_retransmit_timer+0x2a66/0x2e80 net/ipv4/tcp_timer.c:500
Read of size 8 at addr ffff8880644064d0 by task swapper/0/0

CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x188/0x20d lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xd3/0x413 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 tcp_retransmit_timer+0x2a66/0x2e80 net/ipv4/tcp_timer.c:500
 tcp_write_timer_handler+0x686/0x8a0 net/ipv4/tcp_timer.c:611
 tcp_write_timer+0xa2/0x2b0 net/ipv4/tcp_timer.c:631
 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1404
 expire_timers kernel/time/timer.c:1449 [inline]
 __run_timers kernel/time/timer.c:1773 [inline]
 __run_timers kernel/time/timer.c:1740 [inline]
 run_timer_softirq+0x623/0x1600 kernel/time/timer.c:1786
 __do_softirq+0x26c/0x9f7 kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x192/0x1d0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:546 [inline]
 smp_apic_timer_interrupt+0x19e/0x600 arch/x86/kernel/apic/apic.c:1107
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:61
Code: cc cc cc cc cc cc cc cc cc cc cc cc e9 07 00 00 00 0f 00 2d 24 fc 4b 00 f4 c3 66 90 e9 07 00 00 00 0f 00 2d 14 fc 4b 00 fb f4 <c3> cc 41 56 41 55 41 54 55 53 e8 73 c8 84 f9 e8 8e 41 bf fb 0f 1f
RSP: 0018:ffffffff89807c50 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13
RAX: ffffffff89886540 RBX: 0000000000000000 RCX: 1ffffffff1516a22
RDX: 0000000000000000 RSI: ffffffff87dcb648 RDI: ffffffff89886dc0
RBP: ffff88821a867064 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88821a867064
R13: 1ffffffff1300f95 R14: ffff88821a867065 R15: 0000000000000001
 arch_safe_halt arch/x86/include/asm/paravirt.h:144 [inline]
 acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline]
 acpi_safe_halt+0x8d/0x110 drivers/acpi/processor_idle.c:108
 acpi_idle_do_entry+0xa9/0xe0 drivers/acpi/processor_idle.c:525
 acpi_idle_enter+0x437/0xb20 drivers/acpi/processor_idle.c:651
 cpuidle_enter_state+0xdd/0xd60 drivers/cpuidle/cpuidle.c:234
 cpuidle_enter+0x4a/0xa0 drivers/cpuidle/cpuidle.c:345
 call_cpuidle kernel/sched/idle.c:117 [inline]
 cpuidle_idle_call kernel/sched/idle.c:207 [inline]
 do_idle+0x42f/0x690 kernel/sched/idle.c:269
 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:365
 start_kernel+0x97d/0x9ba init/main.c:1040
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:242

Allocated by task 3884:
 save_stack+0x1b/0x40 mm/kasan/common.c:48
 set_track mm/kasan/common.c:56 [inline]
 __kasan_kmalloc mm/kasan/common.c:494 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:467
 slab_post_alloc_hook mm/slab.h:586 [inline]
 slab_alloc mm/slab.c:3320 [inline]
 kmem_cache_alloc+0x11b/0x740 mm/slab.c:3484
 getname_flags fs/namei.c:138 [inline]
 getname_flags+0xd2/0x5b0 fs/namei.c:128
 user_path_at_empty+0x2a/0x50 fs/namei.c:2632
 user_path_at include/linux/namei.h:59 [inline]
 vfs_statx+0x14b/0x370 fs/stat.c:202
 vfs_lstat include/linux/fs.h:3308 [inline]
 __do_sys_newlstat+0x91/0x110 fs/stat.c:374
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3

Freed by task 3884:
 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+0xf7/0x140 mm/kasan/common.c:455
 __cache_free mm/slab.c:3426 [inline]
 kmem_cache_free+0x7f/0x320 mm/slab.c:3694
 putname+0xe1/0x120 fs/namei.c:259
 filename_lookup+0x282/0x3e0 fs/namei.c:2362
 user_path_at include/linux/namei.h:59 [inline]
 vfs_statx+0x14b/0x370 fs/stat.c:202
 vfs_lstat include/linux/fs.h:3308 [inline]
 __do_sys_newlstat+0x91/0x110 fs/stat.c:374
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3

The buggy address belongs to the object at ffff888064406bc0
 which belongs to the cache names_cache of size 4096
The buggy address is located 1776 bytes to the left of
 4096-byte region [ffff888064406bc0, ffff888064407bc0)
The buggy address belongs to the page:
page:ffffea0001910180 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 head:ffffea0001910180 order:1 compound_mapcount:0
flags: 0xfffe0000010200(slab|head)
raw: 00fffe0000010200 ffffea00017bdd08 ffffea00017ac188 ffff8880aa1ec000
raw: 0000000000000000 ffff888064406bc0 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888064406380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888064406400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888064406480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                                 ^
 ffff888064406500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888064406580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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