================================================================== BUG: KASAN: use-after-free in tcp_probe_timer net/ipv4/tcp_timer.c:378 [inline] BUG: KASAN: use-after-free in tcp_write_timer_handler net/ipv4/tcp_timer.c:624 [inline] BUG: KASAN: use-after-free in tcp_write_timer_handler+0x998/0x9f0 net/ipv4/tcp_timer.c:594 Read of size 1 at addr ffff88804c40bda5 by task syz-executor.5/3634 CPU: 0 PID: 3634 Comm: syz-executor.5 Not tainted 6.0.0-rc1-syzkaller-00175-g5003e52c311a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:317 [inline] print_report.cold+0x2ba/0x719 mm/kasan/report.c:433 kasan_report+0xb1/0x1e0 mm/kasan/report.c:495 tcp_probe_timer net/ipv4/tcp_timer.c:378 [inline] tcp_write_timer_handler net/ipv4/tcp_timer.c:624 [inline] tcp_write_timer_handler+0x998/0x9f0 net/ipv4/tcp_timer.c:594 tcp_write_timer+0xa2/0x2b0 net/ipv4/tcp_timer.c:637 call_timer_fn+0x1a0/0x6b0 kernel/time/timer.c:1474 expire_timers kernel/time/timer.c:1519 [inline] __run_timers.part.0+0x674/0xa80 kernel/time/timer.c:1790 __run_timers kernel/time/timer.c:1768 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1803 __do_softirq+0x1d3/0x9c6 kernel/softirq.c:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:650 irq_exit_rcu+0x5/0x20 kernel/softirq.c:662 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:lock_is_held_type+0xff/0x140 kernel/locking/lockdep.c:5714 Code: 00 00 b8 ff ff ff ff 65 0f c1 05 84 28 83 76 83 f8 01 75 29 9c 58 f6 c4 02 75 3d 48 f7 04 24 00 02 00 00 74 01 fb 48 83 c4 08 <44> 89 e8 5b 5d 41 5c 41 5d 41 5e 41 5f c3 45 31 ed eb b9 0f 0b 48 RSP: 0018:ffffc900040bf4b8 EFLAGS: 00000286 RAX: 0000000000000046 RBX: 0000000000000005 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffffff8bf89200 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: ffff88802554bb00 R13: 0000000000000000 R14: 00000000ffffffff R15: ffff88802554c618 lock_is_held include/linux/lockdep.h:283 [inline] rcu_read_lock_sched_held+0x3a/0x70 kernel/rcu/update.c:125 trace_block_touch_buffer include/trace/events/block.h:45 [inline] touch_buffer fs/buffer.c:62 [inline] __find_get_block+0x708/0xe20 fs/buffer.c:1311 __getblk_gfp+0x28/0x80 fs/buffer.c:1329 sb_getblk include/linux/buffer_head.h:352 [inline] __ext4_get_inode_loc+0x366/0x11a0 fs/ext4/inode.c:4472 ext4_get_inode_loc+0xba/0x160 fs/ext4/inode.c:4600 ext4_reserve_inode_write+0xca/0x270 fs/ext4/inode.c:5760 __ext4_mark_inode_dirty+0x176/0x8d0 fs/ext4/inode.c:5929 __ext4_ext_dirty+0x1ae/0x230 fs/ext4/extents.c:183 ext4_ext_remove_space+0x31ca/0x44f0 fs/ext4/extents.c:3056 ext4_ext_truncate+0x33f/0x400 fs/ext4/extents.c:4412 ext4_truncate+0xeb9/0x1430 fs/ext4/inode.c:4257 ext4_evict_inode+0xb68/0x1d40 fs/ext4/inode.c:286 evict+0x2ed/0x6b0 fs/inode.c:665 iput_final fs/inode.c:1748 [inline] iput.part.0+0x55d/0x810 fs/inode.c:1774 iput+0x58/0x70 fs/inode.c:1764 d_delete_notify include/linux/fsnotify.h:261 [inline] vfs_rmdir.part.0+0x496/0x5a0 fs/namei.c:4111 vfs_rmdir fs/namei.c:4083 [inline] do_rmdir+0x3a6/0x430 fs/namei.c:4159 __do_sys_unlinkat fs/namei.c:4339 [inline] __se_sys_unlinkat fs/namei.c:4333 [inline] __x64_sys_unlinkat+0xeb/0x130 fs/namei.c:4333 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7efd5a488be7 Code: 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 07 01 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffd22593c08 EFLAGS: 00000207 ORIG_RAX: 0000000000000107 RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 00007efd5a488be7 RDX: 0000000000000200 RSI: 00007ffd22594d90 RDI: 00000000ffffff9c RBP: 00007ffd22593cd0 R08: 0000000000000000 R09: 00007ffd22593aa0 R10: 00005555565f58e3 R11: 0000000000000207 R12: 00007efd5a4e22ce R13: 00007ffd22594d90 R14: 00005555565f5810 R15: 00007ffd22594dd0 Allocated by task 3637: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:437 [inline] __kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:470 kasan_slab_alloc include/linux/kasan.h:224 [inline] slab_post_alloc_hook mm/slab.h:727 [inline] slab_alloc_node mm/slub.c:3243 [inline] slab_alloc mm/slub.c:3251 [inline] __kmem_cache_alloc_lru mm/slub.c:3258 [inline] kmem_cache_alloc+0x267/0x3b0 mm/slub.c:3268 kmem_cache_zalloc include/linux/slab.h:723 [inline] net_alloc net/core/net_namespace.c:404 [inline] copy_net_ns+0x125/0x760 net/core/net_namespace.c:459 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:227 ksys_unshare+0x445/0x920 kernel/fork.c:3183 __do_sys_unshare kernel/fork.c:3254 [inline] __se_sys_unshare kernel/fork.c:3252 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3252 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 __kasan_record_aux_stack+0xbe/0xd0 mm/kasan/generic.c:348 insert_work+0x48/0x350 kernel/workqueue.c:1358 __queue_work+0x625/0x1210 kernel/workqueue.c:1517 call_timer_fn+0x1a0/0x6b0 kernel/time/timer.c:1474 expire_timers kernel/time/timer.c:1514 [inline] __run_timers.part.0+0x4a3/0xa80 kernel/time/timer.c:1790 __run_timers kernel/time/timer.c:1768 [inline] run_timer_softirq+0x152/0x1d0 kernel/time/timer.c:1805 __do_softirq+0x1d3/0x9c6 kernel/softirq.c:571 The buggy address belongs to the object at ffff88804c40b700 which belongs to the cache net_namespace of size 6784 The buggy address is located 1701 bytes inside of 6784-byte region [ffff88804c40b700, ffff88804c40d180) The buggy address belongs to the physical page: page:ffffea0001310200 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88804c40b700 pfn:0x4c408 head:ffffea0001310200 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea00011ab600 dead000000000002 ffff8881400073c0 raw: ffff88804c40b700 0000000080040003 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3634, tgid 3634 (syz-executor.5), ts 130951803490, free_ts 11444742668 prep_new_page mm/page_alloc.c:2532 [inline] get_page_from_freelist+0x109b/0x2ce0 mm/page_alloc.c:4283 __alloc_pages+0x1c7/0x510 mm/page_alloc.c:5515 alloc_pages+0x1a6/0x270 mm/mempolicy.c:2270 alloc_slab_page mm/slub.c:1824 [inline] allocate_slab+0x27e/0x3d0 mm/slub.c:1969 new_slab mm/slub.c:2029 [inline] ___slab_alloc+0x7f1/0xe10 mm/slub.c:3031 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3118 slab_alloc_node mm/slub.c:3209 [inline] slab_alloc mm/slub.c:3251 [inline] __kmem_cache_alloc_lru mm/slub.c:3258 [inline] kmem_cache_alloc+0x38c/0x3b0 mm/slub.c:3268 kmem_cache_zalloc include/linux/slab.h:723 [inline] net_alloc net/core/net_namespace.c:404 [inline] copy_net_ns+0x125/0x760 net/core/net_namespace.c:459 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:227 ksys_unshare+0x445/0x920 kernel/fork.c:3183 __do_sys_unshare kernel/fork.c:3254 [inline] __se_sys_unshare kernel/fork.c:3252 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3252 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1449 [inline] free_pcp_prepare+0x5e4/0xd20 mm/page_alloc.c:1499 free_unref_page_prepare mm/page_alloc.c:3380 [inline] free_unref_page+0x19/0x4d0 mm/page_alloc.c:3476 free_contig_range+0xb1/0x180 mm/page_alloc.c:9408 destroy_args+0xa8/0x646 mm/debug_vm_pgtable.c:1031 debug_vm_pgtable+0x2945/0x29d6 mm/debug_vm_pgtable.c:1354 do_one_initcall+0xfe/0x650 init/main.c:1296 do_initcall_level init/main.c:1369 [inline] do_initcalls init/main.c:1385 [inline] do_basic_setup init/main.c:1404 [inline] kernel_init_freeable+0x6b1/0x73a init/main.c:1611 kernel_init+0x1a/0x1d0 init/main.c:1500 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Memory state around the buggy address: ffff88804c40bc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88804c40bd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88804c40bd80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88804c40be00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88804c40be80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: b8 ff ff ff ff mov $0xffffffff,%eax 7: 65 0f c1 05 84 28 83 xadd %eax,%gs:0x76832884(%rip) # 0x76832893 e: 76 f: 83 f8 01 cmp $0x1,%eax 12: 75 29 jne 0x3d 14: 9c pushfq 15: 58 pop %rax 16: f6 c4 02 test $0x2,%ah 19: 75 3d jne 0x58 1b: 48 f7 04 24 00 02 00 testq $0x200,(%rsp) 22: 00 23: 74 01 je 0x26 25: fb sti 26: 48 83 c4 08 add $0x8,%rsp * 2a: 44 89 e8 mov %r13d,%eax <-- trapping instruction 2d: 5b pop %rbx 2e: 5d pop %rbp 2f: 41 5c pop %r12 31: 41 5d pop %r13 33: 41 5e pop %r14 35: 41 5f pop %r15 37: c3 retq 38: 45 31 ed xor %r13d,%r13d 3b: eb b9 jmp 0xfffffff6 3d: 0f 0b ud2 3f: 48 rex.W