================================================================== BUG: KASAN: use-after-free in tcp_orphan_retries net/ipv4/tcp_timer.c:139 [inline] BUG: KASAN: use-after-free in tcp_probe_timer net/ipv4/tcp_timer.c:374 [inline] BUG: KASAN: use-after-free in tcp_write_timer_handler+0xa4b/0xa60 net/ipv4/tcp_timer.c:602 Read of size 4 at addr ffff8880a2554968 by task syz-executor.5/7039 CPU: 0 PID: 7039 Comm: syz-executor.5 Not tainted 4.19.189-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+0x1fc/0x2ef lib/dump_stack.c:118 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354 kasan_report mm/kasan/report.c:412 [inline] __asan_report_load4_noabort+0x88/0x90 mm/kasan/report.c:432 tcp_orphan_retries net/ipv4/tcp_timer.c:139 [inline] tcp_probe_timer net/ipv4/tcp_timer.c:374 [inline] tcp_write_timer_handler+0xa4b/0xa60 net/ipv4/tcp_timer.c:602 tcp_write_timer+0x103/0x1b0 net/ipv4/tcp_timer.c:618 call_timer_fn+0x177/0x700 kernel/time/timer.c:1338 expire_timers+0x243/0x4e0 kernel/time/timer.c:1375 __run_timers kernel/time/timer.c:1696 [inline] run_timer_softirq+0x21c/0x670 kernel/time/timer.c:1709 __do_softirq+0x265/0x980 kernel/softirq.c:292 invoke_softirq kernel/softirq.c:372 [inline] irq_exit+0x215/0x260 kernel/softirq.c:412 exiting_irq arch/x86/include/asm/apic.h:535 [inline] smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1098 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894 RIP: 0010:rcu_is_watching+0x7e/0xc0 kernel/rcu/tree.c:1025 Code: 89 ea 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 0f b6 14 02 48 89 e8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 24 8b 43 10 d1 e8 <83> e0 01 65 ff 0d 18 73 b0 7e 74 07 48 83 c4 08 5b 5d c3 e8 2c d1 RSP: 0018:ffff88802c586b90 EFLAGS: 00000202 ORIG_RAX: ffffffffffffff13 RAX: 0000000000058e61 RBX: ffff8880ba022a80 RCX: ffffffff81516bc3 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8880ba022a90 RBP: ffff8880ba022a90 R08: 0000000000000000 R09: ffffed1017404552 R10: ffff8880ba022a93 R11: 0000000000000000 R12: ffff8880a2268930 R13: 0000000000000001 R14: ffffffff8d36cf40 R15: 0000000000000000 rcu_read_lock_held+0xba/0x110 kernel/rcu/update.c:283 blkg_lookup include/linux/blk-cgroup.h:337 [inline] blkcg_bio_issue_check include/linux/blk-cgroup.h:813 [inline] generic_make_request_checks+0xb49/0x22e0 block/blk-core.c:2342 generic_make_request+0x23f/0xdf0 block/blk-core.c:2412 submit_bio+0xb1/0x430 block/blk-core.c:2576 submit_bh_wbc+0x5a7/0x760 fs/buffer.c:3090 __block_write_full_page+0x71a/0xf60 fs/buffer.c:1777 block_write_full_page+0x1f3/0x260 fs/buffer.c:2951 __mpage_writepage+0x6b1/0x1570 fs/mpage.c:678 write_cache_pages+0x802/0x12d0 mm/page-writeback.c:2240 mpage_writepages+0xd1/0x230 fs/mpage.c:730 do_writepages+0xe5/0x290 mm/page-writeback.c:2344 __filemap_fdatawrite_range+0x27d/0x350 mm/filemap.c:446 file_write_and_wait_range+0x93/0x100 mm/filemap.c:776 __generic_file_fsync+0x74/0x1f0 fs/libfs.c:985 fat_file_fsync+0x73/0x200 fs/fat/file.c:198 vfs_fsync_range+0x13a/0x220 fs/sync.c:197 generic_write_sync include/linux/fs.h:2750 [inline] generic_file_write_iter+0x4be/0x730 mm/filemap.c:3327 call_write_iter include/linux/fs.h:1821 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x51b/0x770 fs/read_write.c:487 __kernel_write+0x109/0x370 fs/read_write.c:506 write_pipe_buf+0x153/0x1f0 fs/splice.c:798 splice_from_pipe_feed fs/splice.c:503 [inline] __splice_from_pipe+0x389/0x800 fs/splice.c:627 splice_from_pipe fs/splice.c:662 [inline] default_file_splice_write+0xd8/0x180 fs/splice.c:810 do_splice_from fs/splice.c:852 [inline] direct_splice_actor+0x115/0x160 fs/splice.c:1025 splice_direct_to_actor+0x33f/0x8d0 fs/splice.c:980 do_splice_direct+0x1a7/0x270 fs/splice.c:1068 do_sendfile+0x550/0xc30 fs/read_write.c:1447 __do_sys_sendfile64 fs/read_write.c:1508 [inline] __se_sys_sendfile64+0x147/0x160 fs/read_write.c:1494 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4665f9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f22df76a188 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9 RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000004 RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000001c500 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffd06e045cf R14: 00007f22df76a300 R15: 0000000000022000 Allocated by task 10390: kmem_cache_alloc+0x122/0x370 mm/slab.c:3559 kmem_cache_zalloc include/linux/slab.h:699 [inline] net_alloc net/core/net_namespace.c:385 [inline] copy_net_ns+0x106/0x340 net/core/net_namespace.c:425 create_new_namespaces+0x3f6/0x7b0 kernel/nsproxy.c:107 unshare_nsproxy_namespaces+0xbd/0x1f0 kernel/nsproxy.c:206 ksys_unshare+0x36c/0x9a0 kernel/fork.c:2541 __do_sys_unshare kernel/fork.c:2609 [inline] __se_sys_unshare kernel/fork.c:2607 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:2607 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 33: __cache_free mm/slab.c:3503 [inline] kmem_cache_free+0x7f/0x260 mm/slab.c:3765 net_free net/core/net_namespace.c:401 [inline] net_drop_ns+0x73/0x90 net/core/net_namespace.c:408 cleanup_net+0x64c/0x8b0 net/core/net_namespace.c:571 process_one_work+0x864/0x1570 kernel/workqueue.c:2152 worker_thread+0x64c/0x1130 kernel/workqueue.c:2295 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 The buggy address belongs to the object at ffff8880a2554200 which belongs to the cache net_namespace of size 8704 The buggy address is located 1896 bytes inside of 8704-byte region [ffff8880a2554200, ffff8880a2556400) The buggy address belongs to the page: page:ffffea0002895500 count:1 mapcount:0 mapping:ffff88823b843e00 index:0x0 compound_mapcount: 0 flags: 0xfff00000008100(slab|head) raw: 00fff00000008100 ffffea000117be08 ffffea0002c5ba08 ffff88823b843e00 raw: 0000000000000000 ffff8880a2554200 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880a2554800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a2554880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880a2554900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880a2554980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880a2554a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================