================================================================== BUG: KASAN: use-after-free in tcp_retransmit_timer+0x2ef3/0x3360 net/ipv4/tcp_timer.c:511 Read of size 8 at addr ffff88807de31e40 by task dhcpcd-run-hook/30553 CPU: 0 PID: 30553 Comm: dhcpcd-run-hook Not tainted 5.18.0-rc3-syzkaller-00494-ga0df71948e95 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0xeb/0x495 mm/kasan/report.c:313 print_report mm/kasan/report.c:429 [inline] kasan_report.cold+0xf4/0x1c6 mm/kasan/report.c:491 tcp_retransmit_timer+0x2ef3/0x3360 net/ipv4/tcp_timer.c:511 tcp_write_timer_handler+0x5e6/0xbc0 net/ipv4/tcp_timer.c:622 tcp_write_timer+0xa2/0x2b0 net/ipv4/tcp_timer.c:642 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers.part.0+0x679/0xa80 kernel/time/timer.c:1737 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1750 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:645 RIP: 0010:instrument_atomic_read include/linux/instrumented.h:71 [inline] RIP: 0010:atomic_read include/linux/atomic/atomic-instrumented.h:27 [inline] RIP: 0010:folio_memcg_lock+0x182/0x6c0 mm/memcontrol.c:2039 Code: eb cb 81 58 e8 4f b1 91 ff 4d 85 ed 0f 85 40 03 00 00 9c 58 f6 c4 02 0f 85 e2 03 00 00 4d 85 ed 74 01 fb 4c 8d ab 40 11 00 00 04 00 00 00 4c 89 ef e8 21 d6 f8 ff 4c 89 e8 48 c1 e8 03 42 0f RSP: 0018:ffffc900033bf660 EFLAGS: 00000206 RAX: 0000000000000002 RBX: ffff888010e70000 RCX: 1ffffffff200e946 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900033bf6b0 R08: 0000000000000001 R09: ffffffff9006d917 R10: 0000000000000001 R11: 0000000000000001 R12: dffffc0000000000 R13: ffff888010e71140 R14: ffffea000026e038 R15: ffffea000026e008 page_remove_rmap+0x27/0x1510 mm/rmap.c:1377 zap_pte_range mm/memory.c:1389 [inline] zap_pmd_range mm/memory.c:1497 [inline] zap_pud_range mm/memory.c:1526 [inline] zap_p4d_range mm/memory.c:1547 [inline] unmap_page_range+0xffa/0x3fa0 mm/memory.c:1568 unmap_single_vma+0x198/0x310 mm/memory.c:1613 unmap_vmas+0x16b/0x2f0 mm/memory.c:1645 exit_mmap+0x1c4/0x4a0 mm/mmap.c:3148 __mmput+0x122/0x4b0 kernel/fork.c:1183 mmput+0x56/0x60 kernel/fork.c:1205 exec_mmap fs/exec.c:1034 [inline] begin_new_exec+0x101b/0x2f70 fs/exec.c:1293 load_elf_binary+0x15a3/0x4ec0 fs/binfmt_elf.c:1002 search_binary_handler fs/exec.c:1726 [inline] exec_binprm fs/exec.c:1767 [inline] bprm_execve fs/exec.c:1836 [inline] bprm_execve+0x7ef/0x1970 fs/exec.c:1798 do_execveat_common+0x727/0x890 fs/exec.c:1941 do_execve fs/exec.c:2011 [inline] __do_sys_execve fs/exec.c:2087 [inline] __se_sys_execve fs/exec.c:2082 [inline] __x64_sys_execve+0x8f/0xc0 fs/exec.c:2082 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+0x44/0xae RIP: 0033:0x7f1179ba7337 Code: Unable to access opcode bytes at RIP 0x7f1179ba730d. RSP: 002b:00007ffeb9d9ae98 EFLAGS: 00000246 ORIG_RAX: 000000000000003b RAX: ffffffffffffffda RBX: 000055ceb05bc0a8 RCX: 00007f1179ba7337 RDX: 000055ceb05b21b8 RSI: 000055ceb05bc0a8 RDI: 000055ceb05b2268 RBP: 000055ceb05b2268 R08: 000055ceb05b2271 R09: 00007f1179c99a60 R10: 000055ceb05b2500 R11: 0000000000000246 R12: 000055ceb05b21b8 R13: 00007f1179d4cff4 R14: 000055ceb05b21b8 R15: 0000000000000000 Allocated by task 4456: 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:436 [inline] __kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:469 kasan_slab_alloc include/linux/kasan.h:224 [inline] slab_post_alloc_hook mm/slab.h:749 [inline] slab_alloc_node mm/slub.c:3217 [inline] slab_alloc mm/slub.c:3225 [inline] __kmem_cache_alloc_lru mm/slub.c:3232 [inline] kmem_cache_alloc+0x204/0x3b0 mm/slub.c:3242 kmem_cache_zalloc include/linux/slab.h:704 [inline] net_alloc net/core/net_namespace.c:403 [inline] copy_net_ns+0x125/0x760 net/core/net_namespace.c:458 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226 ksys_unshare+0x445/0x920 kernel/fork.c:3132 __do_sys_unshare kernel/fork.c:3203 [inline] __se_sys_unshare kernel/fork.c:3201 [inline] __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3201 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+0x44/0xae 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+0x62e/0x1140 kernel/workqueue.c:1517 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1461 [inline] __run_timers.part.0+0x4a3/0xa80 kernel/time/timer.c:1737 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0x152/0x1d0 kernel/time/timer.c:1752 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 Second to 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+0x62e/0x1140 kernel/workqueue.c:1517 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1461 [inline] __run_timers.part.0+0x4a3/0xa80 kernel/time/timer.c:1737 __run_timers kernel/time/timer.c:1715 [inline] run_timer_softirq+0x152/0x1d0 kernel/time/timer.c:1752 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 The buggy address belongs to the object at ffff88807de31b80 which belongs to the cache net_namespace of size 6784 The buggy address is located 704 bytes inside of 6784-byte region [ffff88807de31b80, ffff88807de33600) The buggy address belongs to the physical page: page:ffffea0001f78c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88807de31b80 pfn:0x7de30 head:ffffea0001f78c00 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff888078240b41 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffff888010dce288 ffffea00017b7608 ffff888010dcd3c0 raw: ffff88807de31b80 0000000000040000 00000001ffffffff ffff888078240b41 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4248, tgid 4246 (syz-executor.3), ts 125258896863, free_ts 125238288152 prep_new_page mm/page_alloc.c:2441 [inline] get_page_from_freelist+0xba2/0x3e00 mm/page_alloc.c:4182 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5408 alloc_pages+0x1aa/0x310 mm/mempolicy.c:2272 alloc_slab_page mm/slub.c:1799 [inline] allocate_slab+0x26c/0x3c0 mm/slub.c:1944 new_slab mm/slub.c:2004 [inline] ___slab_alloc+0x8df/0xf20 mm/slub.c:3005 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3092 slab_alloc_node mm/slub.c:3183 [inline] slab_alloc mm/slub.c:3225 [inline] __kmem_cache_alloc_lru mm/slub.c:3232 [inline] kmem_cache_alloc+0x360/0x3b0 mm/slub.c:3242 kmem_cache_zalloc include/linux/slab.h:704 [inline] net_alloc net/core/net_namespace.c:403 [inline] copy_net_ns+0x125/0x760 net/core/net_namespace.c:458 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 copy_namespaces+0x391/0x450 kernel/nsproxy.c:178 copy_process+0x2f79/0x6fe0 kernel/fork.c:2237 kernel_clone+0xe7/0xab0 kernel/fork.c:2639 __do_sys_clone+0xc8/0x110 kernel/fork.c:2756 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+0x44/0xae page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1356 [inline] free_pcp_prepare+0x549/0xd20 mm/page_alloc.c:1406 free_unref_page_prepare mm/page_alloc.c:3328 [inline] free_unref_page+0x19/0x6a0 mm/page_alloc.c:3423 __unfreeze_partials+0x17c/0x1a0 mm/slub.c:2523 qlink_free mm/kasan/quarantine.c:157 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:446 kasan_slab_alloc include/linux/kasan.h:224 [inline] slab_post_alloc_hook mm/slab.h:749 [inline] slab_alloc_node mm/slub.c:3217 [inline] slab_alloc mm/slub.c:3225 [inline] __kmalloc+0x200/0x350 mm/slub.c:4410 kmalloc include/linux/slab.h:586 [inline] kzalloc include/linux/slab.h:714 [inline] ops_init+0xfb/0x470 net/core/net_namespace.c:124 setup_net+0x5d1/0xc50 net/core/net_namespace.c:325 copy_net_ns+0x318/0x760 net/core/net_namespace.c:471 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 copy_namespaces+0x391/0x450 kernel/nsproxy.c:178 copy_process+0x2f79/0x6fe0 kernel/fork.c:2237 kernel_clone+0xe7/0xab0 kernel/fork.c:2639 __do_sys_clone+0xc8/0x110 kernel/fork.c:2756 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 Memory state around the buggy address: ffff88807de31d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807de31d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807de31e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807de31e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807de31f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: eb cb jmp 0xffffffcd 2: 81 58 e8 4f b1 91 ff sbbl $0xff91b14f,-0x18(%rax) 9: 4d 85 ed test %r13,%r13 c: 0f 85 40 03 00 00 jne 0x352 12: 9c pushfq 13: 58 pop %rax 14: f6 c4 02 test $0x2,%ah 17: 0f 85 e2 03 00 00 jne 0x3ff 1d: 4d 85 ed test %r13,%r13 20: 74 01 je 0x23 22: fb sti 23: 4c 8d ab 40 11 00 00 lea 0x1140(%rbx),%r13 * 2a: be 04 00 00 00 mov $0x4,%esi <-- trapping instruction 2f: 4c 89 ef mov %r13,%rdi 32: e8 21 d6 f8 ff callq 0xfff8d658 37: 4c 89 e8 mov %r13,%rax 3a: 48 c1 e8 03 shr $0x3,%rax 3e: 42 rex.X 3f: 0f .byte 0xf