==================================================================
BUG: KASAN: use-after-free in tcp_retransmit_timer+0x2ef3/0x3360 net/ipv4/tcp_timer.c:511
Read of size 8 at addr ffff88807ad49e40 by task syz-executor.3/31127

CPU: 0 PID: 31127 Comm: syz-executor.3 Not tainted 5.18.0-rc3-syzkaller-01632-gc272e2591169 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __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
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:645
RIP: 0010:__sanitizer_cov_trace_pc+0x59/0x60 kernel/kcov.c:208
Code: 74 2b 8b 82 80 15 00 00 83 f8 02 75 20 48 8b 8a 88 15 00 00 8b 92 84 15 00 00 48 8b 01 48 83 c0 01 48 39 c2 76 07 48 89 34 c1 <48> 89 01 c3 0f 1f 00 41 55 41 54 49 89 fc 55 48 bd eb 83 b5 80 46
RSP: 0018:ffffc9000b1471d0 EFLAGS: 00000212
RAX: 000000000000354b RBX: 0000000000000001 RCX: ffffc9000c425000
RDX: 0000000000040000 RSI: ffffffff819ff55b RDI: 0000000000000003
RBP: ffffc9000b147270 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff819ff6ab R11: 000000000000003f R12: ffff88801bb72680
R13: ffffea0000790a80 R14: ffff88801b8398f0 R15: dffffc0000000000
 xa_is_internal include/linux/xarray.h:170 [inline]
 xa_is_sibling include/linux/xarray.h:1250 [inline]
 xas_reload+0x11b/0x440 include/linux/xarray.h:1562
 mapping_get_entry mm/filemap.c:1897 [inline]
 __filemap_get_folio+0x230/0xf00 mm/filemap.c:1946
 pagecache_get_page+0x2e/0x290 mm/folio-compat.c:126
 find_get_page_flags include/linux/pagemap.h:571 [inline]
 ext4_mb_load_buddy_gfp+0x626/0x1350 fs/ext4/mballoc.c:1568
 ext4_mb_load_buddy fs/ext4/mballoc.c:1616 [inline]
 ext4_mb_regular_allocator+0xb67/0x3610 fs/ext4/mballoc.c:2754
 ext4_mb_new_blocks+0x236e/0x4f50 fs/ext4/mballoc.c:5616
 ext4_ext_map_blocks+0x218d/0x5f60 fs/ext4/extents.c:4281
 ext4_map_blocks+0x653/0x18a0 fs/ext4/inode.c:636
 ext4_getblk+0x144/0x6b0 fs/ext4/inode.c:847
 ext4_bread+0x2a/0x1c0 fs/ext4/inode.c:900
 ext4_append+0x177/0x3a0 fs/ext4/namei.c:67
 ext4_init_new_dir+0x25e/0x4d0 fs/ext4/namei.c:2893
 ext4_mkdir+0x3cf/0xb20 fs/ext4/namei.c:2939
 vfs_mkdir+0x1c3/0x3b0 fs/namei.c:3931
 do_mkdirat+0x285/0x300 fs/namei.c:3957
 __do_sys_mkdir fs/namei.c:3977 [inline]
 __se_sys_mkdir fs/namei.c:3975 [inline]
 __x64_sys_mkdir+0xf2/0x140 fs/namei.c:3975
 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: 0033:0x7fb9862890e9
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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb987331168 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007fb98639bf60 RCX: 00007fb9862890e9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000280
RBP: 00007fb9862e308d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc7d439daf R14: 00007fb987331300 R15: 0000000000022000
 </TASK>

Allocated by task 21472:
 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

The buggy address belongs to the object at ffff88807ad49b80
 which belongs to the cache net_namespace of size 6784
The buggy address is located 704 bytes inside of
 6784-byte region [ffff88807ad49b80, ffff88807ad4b600)

The buggy address belongs to the physical page:
page:ffffea0001eb5200 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88807ad49b80 pfn:0x7ad48
head:ffffea0001eb5200 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff888011bb92c1
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea000110b408 ffffea0001169208 ffff8881400063c0
raw: ffff88807ad49b80 0000000000040002 00000001ffffffff ffff888011bb92c1
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 3627, tgid 3627 (syz-executor.2), ts 132227543314, free_ts 124064303293
 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
 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
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]
 kmem_cache_alloc_node+0x255/0x3f0 mm/slub.c:3267
 __alloc_skb+0x215/0x340 net/core/skbuff.c:414
 alloc_skb_fclone include/linux/skbuff.h:1390 [inline]
 tcp_stream_alloc_skb+0x66/0x900 net/ipv4/tcp.c:862
 tcp_sendmsg_locked+0xac8/0x2fb0 net/ipv4/tcp.c:1297
 tcp_sendmsg+0x2b/0x40 net/ipv4/tcp.c:1448
 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:819
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:725
 sock_write_iter+0x283/0x3c0 net/socket.c:1061
 call_write_iter include/linux/fs.h:2050 [inline]
 new_sync_write+0x38a/0x560 fs/read_write.c:504
 vfs_write+0x7c0/0xac0 fs/read_write.c:591

Memory state around the buggy address:
 ffff88807ad49d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807ad49d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807ad49e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                           ^
 ffff88807ad49e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807ad49f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
----------------
Code disassembly (best guess):
   0:	74 2b                	je     0x2d
   2:	8b 82 80 15 00 00    	mov    0x1580(%rdx),%eax
   8:	83 f8 02             	cmp    $0x2,%eax
   b:	75 20                	jne    0x2d
   d:	48 8b 8a 88 15 00 00 	mov    0x1588(%rdx),%rcx
  14:	8b 92 84 15 00 00    	mov    0x1584(%rdx),%edx
  1a:	48 8b 01             	mov    (%rcx),%rax
  1d:	48 83 c0 01          	add    $0x1,%rax
  21:	48 39 c2             	cmp    %rax,%rdx
  24:	76 07                	jbe    0x2d
  26:	48 89 34 c1          	mov    %rsi,(%rcx,%rax,8)
* 2a:	48 89 01             	mov    %rax,(%rcx) <-- trapping instruction
  2d:	c3                   	retq
  2e:	0f 1f 00             	nopl   (%rax)
  31:	41 55                	push   %r13
  33:	41 54                	push   %r12
  35:	49 89 fc             	mov    %rdi,%r12
  38:	55                   	push   %rbp
  39:	48                   	rex.W
  3a:	bd eb 83 b5 80       	mov    $0x80b583eb,%ebp
  3f:	46                   	rex.RX