================================================================== BUG: KASAN: use-after-free in tcp_probe_timer net/ipv4/tcp_timer.c:360 [inline] BUG: KASAN: use-after-free in tcp_write_timer_handler+0x8c6/0x8d0 net/ipv4/tcp_timer.c:596 Read of size 4 at addr ffff88808b516690 by task syz-executor.2/21419 CPU: 1 PID: 21419 Comm: syz-executor.2 Not tainted 5.3.0-rc5+ #176 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:__find_get_block+0x289/0xdb0 fs/buffer.c:1294 Code: ff df 48 c1 ea 03 80 3c 02 00 0f 85 1c 0a 00 00 48 83 3d 69 f7 0d 07 00 0f 84 41 08 00 00 e8 6e 75 ad ff fb 66 0f 1f 44 00 00 <4d> 85 ff 0f 84 f1 01 00 00 e8 59 75 ad ff 0f 1f 44 00 00 e8 4f 75 RSP: 0018:ffff8880a0dc7a68 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13 RAX: ffff888059aee400 RBX: ffff88805d9d9000 RCX: 1ffffffff134b56e RDX: 0000000000000000 RSI: ffffffff81c4fbc2 RDI: ffffffff81c4fb90 RBP: ffff8880a0dc7ac8 R08: ffff888059aee400 R09: ffffed100bb3b20d R10: ffffed100bb3b20c R11: ffff88805d9d9063 R12: 0000000000000000 R13: 0000000000000438 R14: 0000000000000000 R15: ffff88805d9d9000 sb_find_get_block include/linux/buffer_head.h:338 [inline] recently_deleted fs/ext4/ialloc.c:682 [inline] find_inode_bit.isra.0+0x202/0x520 fs/ext4/ialloc.c:722 __ext4_new_inode+0x16ad/0x4e50 fs/ext4/ialloc.c:914 ext4_symlink+0x45a/0xf10 fs/ext4/namei.c:3262 vfs_symlink fs/namei.c:4127 [inline] vfs_symlink+0x373/0x5a0 fs/namei.c:4113 do_symlinkat+0x22b/0x290 fs/namei.c:4154 __do_sys_symlink fs/namei.c:4173 [inline] __se_sys_symlink fs/namei.c:4171 [inline] __x64_sys_symlink+0x59/0x80 fs/namei.c:4171 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4595a7 Code: 0f 1f 00 b8 5c 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 bd ba fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 58 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 9d ba fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fffe1e433a8 EFLAGS: 00000202 ORIG_RAX: 0000000000000058 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004595a7 RDX: 00007fffe1e43447 RSI: 00000000004bf0f0 RDI: 00007fffe1e43430 RBP: 0000000000000000 R08: 0000000000000800 R09: 0000000000000017 R10: 0000000000000075 R11: 0000000000000202 R12: 0000000000000001 R13: 00007fffe1e433e0 R14: 0000000000000000 R15: 00007fffe1e433f0 Allocated by task 21056: 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_slab_alloc+0xf/0x20 mm/kasan/common.c:495 slab_post_alloc_hook mm/slab.h:520 [inline] slab_alloc mm/slab.c:3319 [inline] kmem_cache_alloc+0x121/0x710 mm/slab.c:3483 getname_kernel+0x53/0x370 fs/namei.c:218 kern_path+0x20/0x40 fs/namei.c:2432 tomoyo_realpath_nofollow+0x74/0xdb security/tomoyo/realpath.c:336 tomoyo_find_next_domain+0x280/0x1f6c security/tomoyo/domain.c:725 tomoyo_bprm_check_security security/tomoyo/tomoyo.c:107 [inline] tomoyo_bprm_check_security+0x124/0x1b0 security/tomoyo/tomoyo.c:97 security_bprm_check+0x63/0xb0 security/security.c:750 search_binary_handler+0x71/0x570 fs/exec.c:1645 exec_binprm fs/exec.c:1701 [inline] __do_execve_file.isra.0+0x1333/0x2340 fs/exec.c:1821 do_execveat_common fs/exec.c:1868 [inline] do_execve fs/exec.c:1885 [inline] __do_sys_execve fs/exec.c:1961 [inline] __se_sys_execve fs/exec.c:1956 [inline] __x64_sys_execve+0x8f/0xc0 fs/exec.c:1956 do_syscall_64+0xfd/0x6a0 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 21056: 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] kmem_cache_free+0x86/0x320 mm/slab.c:3693 putname+0xef/0x130 fs/namei.c:259 filename_lookup+0x28f/0x410 fs/namei.c:2355 kern_path+0x36/0x40 fs/namei.c:2432 tomoyo_realpath_nofollow+0x74/0xdb security/tomoyo/realpath.c:336 tomoyo_find_next_domain+0x280/0x1f6c security/tomoyo/domain.c:725 tomoyo_bprm_check_security security/tomoyo/tomoyo.c:107 [inline] tomoyo_bprm_check_security+0x124/0x1b0 security/tomoyo/tomoyo.c:97 security_bprm_check+0x63/0xb0 security/security.c:750 search_binary_handler+0x71/0x570 fs/exec.c:1645 exec_binprm fs/exec.c:1701 [inline] __do_execve_file.isra.0+0x1333/0x2340 fs/exec.c:1821 do_execveat_common fs/exec.c:1868 [inline] do_execve fs/exec.c:1885 [inline] __do_sys_execve fs/exec.c:1961 [inline] __se_sys_execve fs/exec.c:1956 [inline] __x64_sys_execve+0x8f/0xc0 fs/exec.c:1956 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 ffff88808b516440 which belongs to the cache names_cache of size 4096 The buggy address is located 592 bytes inside of 4096-byte region [ffff88808b516440, ffff88808b517440) The buggy address belongs to the page: page:ffffea00022d4580 refcount:1 mapcount:0 mapping:ffff88821bc46380 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea000251c808 ffffea00022e2608 ffff88821bc46380 raw: 0000000000000000 ffff88808b516440 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88808b516580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88808b516600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88808b516680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88808b516700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88808b516780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================