================================================================== BUG: KASAN: slab-out-of-bounds in tcp_probe_timer net/ipv4/tcp_timer.c:360 [inline] BUG: KASAN: slab-out-of-bounds in tcp_write_timer_handler+0x8c6/0x8d0 net/ipv4/tcp_timer.c:596 Read of size 4 at addr ffff8880970b4850 by task modprobe/9857 CPU: 1 PID: 9857 Comm: modprobe Not tainted 5.3.0-rc3+ #155 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+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0xd4/0x306 mm/kasan/report.c:351 __kasan_report.cold+0x1b/0x36 mm/kasan/report.c:482 kasan_report+0x12/0x17 mm/kasan/common.c:612 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131 tcp_probe_timer net/ipv4/tcp_timer.c:360 [inline] tcp_write_timer_handler+0x8c6/0x8d0 net/ipv4/tcp_timer.c:596 tcp_write_timer+0xa8/0x1e0 net/ipv4/tcp_timer.c:612 call_timer_fn+0x1ac/0x780 kernel/time/timer.c:1322 expire_timers kernel/time/timer.c:1366 [inline] __run_timers kernel/time/timer.c:1685 [inline] __run_timers kernel/time/timer.c:1653 [inline] run_timer_softirq+0x697/0x17a0 kernel/time/timer.c:1698 __do_softirq+0x262/0x98c kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x19b/0x1e0 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:537 [inline] smp_apic_timer_interrupt+0x1a3/0x610 arch/x86/kernel/apic/apic.c:1095 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:768 [inline] RIP: 0010:kmem_cache_free+0xab/0x320 mm/slab.c:3694 Code: e8 1a 27 00 00 84 c0 74 77 41 f7 c6 00 02 00 00 74 4f e8 98 ab cb ff 48 83 3d 20 99 26 07 00 0f 84 fa 01 00 00 4c 89 f7 57 9d <0f> 1f 44 00 00 4c 8b 6d 08 0f 1f 44 00 00 65 8b 05 40 39 55 7e 83 RSP: 0018:ffff88808d77fb48 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000007 RBX: ffff888066b4b620 RCX: 1ffffffff134b4de RDX: 0000000000000000 RSI: ffffffff817805de RDI: 0000000000000286 RBP: ffff88808d77fb68 R08: ffff888064fb6300 R09: fffffbfff134aea0 R10: fffffbfff134ae9f R11: ffffffff89a574ff R12: ffff88821bc42700 R13: ffffffff81a23167 R14: 0000000000000286 R15: ffff8880a675f7e0 anon_vma_chain_free mm/rmap.c:134 [inline] unlink_anon_vmas+0x487/0x860 mm/rmap.c:419 free_pgtables+0x1af/0x2f0 mm/memory.c:395 exit_mmap+0x2c9/0x530 mm/mmap.c:3146 __mmput kernel/fork.c:1064 [inline] mmput+0x179/0x4d0 kernel/fork.c:1085 exit_mm kernel/exit.c:547 [inline] do_exit+0x84e/0x2e50 kernel/exit.c:866 do_group_exit+0x135/0x360 kernel/exit.c:983 __do_sys_exit_group kernel/exit.c:994 [inline] __se_sys_exit_group kernel/exit.c:992 [inline] __x64_sys_exit_group+0x44/0x50 kernel/exit.c:992 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f0f9a38e1e8 Code: Bad RIP value. RSP: 002b:00007ffd63394c98 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f0f9a38e1e8 RDX: 0000000000000001 RSI: 000000000000003c RDI: 0000000000000001 RBP: 00007f0f9a663840 R08: 00000000000000e7 R09: ffffffffffffffa8 R10: 00007f0f9a669740 R11: 0000000000000246 R12: 00007f0f9a663840 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 3909: save_stack+0x23/0x90 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] __kasan_kmalloc mm/kasan/common.c:487 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:460 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:501 kmem_cache_alloc_trace+0x158/0x790 mm/slab.c:3550 kmalloc include/linux/slab.h:552 [inline] kzalloc include/linux/slab.h:748 [inline] kernfs_iop_get_link fs/kernfs/symlink.c:135 [inline] kernfs_iop_get_link+0x6a/0x680 fs/kernfs/symlink.c:126 vfs_readlink+0x201/0x3e0 fs/namei.c:4736 do_readlinkat+0x2ab/0x320 fs/stat.c:411 __do_sys_readlink fs/stat.c:432 [inline] __se_sys_readlink fs/stat.c:429 [inline] __x64_sys_readlink+0x78/0xb0 fs/stat.c:429 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 3909: save_stack+0x23/0x90 mm/kasan/common.c:69 set_track mm/kasan/common.c:77 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:449 kasan_slab_free+0xe/0x10 mm/kasan/common.c:457 __cache_free mm/slab.c:3425 [inline] kfree+0x10a/0x2c0 mm/slab.c:3756 kfree_link+0x16/0x20 fs/libfs.c:1124 do_delayed_call include/linux/delayed_call.h:28 [inline] vfs_readlink+0x16e/0x3e0 fs/namei.c:4741 do_readlinkat+0x2ab/0x320 fs/stat.c:411 __do_sys_readlink fs/stat.c:432 [inline] __se_sys_readlink fs/stat.c:429 [inline] __x64_sys_readlink+0x78/0xb0 fs/stat.c:429 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff8880970b4b40 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 752 bytes to the left of 4096-byte region [ffff8880970b4b40, ffff8880970b5b40) The buggy address belongs to the page: page:ffffea00025c2d00 refcount:1 mapcount:0 mapping:ffff8880aa402000 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea00022aab08 ffffea0001860808 ffff8880aa402000 raw: 0000000000000000 ffff8880970b4b40 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880970b4700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880970b4780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880970b4800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff8880970b4880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880970b4900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================