================================================================== BUG: KASAN: use-after-free in ext4_htree_fill_tree+0x1066/0x10d0 fs/ext4/namei.c:1246 Read of size 1 at addr ffff888121b7f365 by task syz-executor/2633 CPU: 0 PID: 2633 Comm: syz-executor Not tainted 6.1.129-syzkaller-1168473-g70d648657b1e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:88 dump_stack_lvl+0xee/0x158 lib/dump_stack.c:106 print_address_description+0x71/0x210 mm/kasan/report.c:316 print_report+0x4a/0x60 mm/kasan/report.c:427 kasan_report+0x122/0x150 mm/kasan/report.c:531 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report_generic.c:348 ext4_htree_fill_tree+0x1066/0x10d0 fs/ext4/namei.c:1246 ext4_dx_readdir fs/ext4/dir.c:605 [inline] ext4_readdir+0x2d60/0x3bd0 fs/ext4/dir.c:142 iterate_dir+0x260/0x600 fs/readdir.c:-1 __do_sys_getdents64 fs/readdir.c:369 [inline] __se_sys_getdents64+0xe5/0x240 fs/readdir.c:354 __x64_sys_getdents64+0x7b/0x90 fs/readdir.c:354 x64_sys_call+0x15c/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:218 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7ff6ae5bf753 Code: c1 66 0f 1f 44 00 00 48 83 c4 08 48 89 ef 5b 5d e9 52 3e f8 ff 66 90 b8 ff ff ff 7f 48 39 c2 48 0f 47 d0 b8 d9 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 05 c3 0f 1f 40 00 48 c7 c2 a8 ff ff ff f7 d8 RSP: 002b:00007fff80cd6728 EFLAGS: 00000293 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 000055558c94a4e0 RCX: 00007ff6ae5bf753 RDX: 0000000000008000 RSI: 000055558c94a4e0 RDI: 0000000000000005 RBP: 000055558c94a4b4 R08: 0000000000028b61 R09: 0000000000000000 R10: 00007ff6ae77cca0 R11: 0000000000000293 R12: ffffffffffffffa8 R13: 0000000000000010 R14: 000055558c94a4b0 R15: 00007fff80cd89e0 Allocated by task 2481: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_alloc_info+0x25/0x30 mm/kasan/generic.c:505 ____kasan_kmalloc mm/kasan/common.c:379 [inline] __kasan_kmalloc+0x95/0xb0 mm/kasan/common.c:388 kasan_kmalloc include/linux/kasan.h:212 [inline] kmalloc_trace+0x40/0xb0 mm/slab_common.c:1033 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] ipv6_add_dev+0x10e/0x1230 net/ipv6/addrconf.c:381 addrconf_notify+0x6d5/0xe40 net/ipv6/addrconf.c:3620 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0x90/0x100 kernel/notifier.c:455 call_netdevice_notifiers_info net/core/dev.c:1978 [inline] call_netdevice_notifiers_extack net/core/dev.c:2016 [inline] call_netdevice_notifiers+0x111/0x190 net/core/dev.c:2030 register_netdevice+0x10b4/0x1470 net/core/dev.c:10158 veth_newlink+0x7a0/0xbe0 drivers/net/veth.c:1775 rtnl_newlink_create net/core/rtnetlink.c:3419 [inline] __rtnl_newlink net/core/rtnetlink.c:3639 [inline] rtnl_newlink+0x149d/0x1fc0 net/core/rtnetlink.c:3652 rtnetlink_rcv_msg+0x9d8/0xcd0 net/core/rtnetlink.c:6150 netlink_rcv_skb+0x1de/0x420 net/netlink/af_netlink.c:2503 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:6168 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline] netlink_unicast+0x89f/0xa20 net/netlink/af_netlink.c:1338 netlink_sendmsg+0x8aa/0xbc0 net/netlink/af_netlink.c:1860 sock_sendmsg_nosec net/socket.c:716 [inline] __sock_sendmsg net/socket.c:728 [inline] __sys_sendto+0x44f/0x5c0 net/socket.c:2143 __do_sys_sendto net/socket.c:2155 [inline] __se_sys_sendto net/socket.c:2151 [inline] __x64_sys_sendto+0xe5/0x100 net/socket.c:2151 x64_sys_call+0x83/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb6/0xc0 mm/kasan/generic.c:486 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:496 __call_rcu_common kernel/rcu/tree.c:2807 [inline] call_rcu+0xd4/0xf90 kernel/rcu/tree.c:2926 in6_dev_finish_destroy+0x177/0x1d0 net/ipv6/addrconf_core.c:278 in6_dev_put include/net/addrconf.h:408 [inline] addrconf_ifdown+0x16ce/0x1910 net/ipv6/addrconf.c:3979 addrconf_notify+0x39f/0xe40 net/ipv6/addrconf.c:-1 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0x90/0x100 kernel/notifier.c:455 call_netdevice_notifiers_info net/core/dev.c:1978 [inline] call_netdevice_notifiers_extack net/core/dev.c:2016 [inline] call_netdevice_notifiers net/core/dev.c:2030 [inline] unregister_netdevice_many+0xf71/0x17f0 net/core/dev.c:10908 default_device_exit_batch+0x9ab/0xa40 net/core/dev.c:11421 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x5fd/0xad0 net/core/net_namespace.c:604 process_one_work+0x70e/0xc20 kernel/workqueue.c:2299 worker_thread+0xa29/0x11f0 kernel/workqueue.c:2446 kthread+0x270/0x310 kernel/kthread.c:386 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Second to last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb6/0xc0 mm/kasan/generic.c:486 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:496 kvfree_call_rcu+0x95/0x7a0 kernel/rcu/tree.c:3445 drop_sysctl_table+0x2ef/0x410 fs/proc/proc_sysctl.c:1727 unregister_sysctl_table+0x75/0x120 fs/proc/proc_sysctl.c:1765 unregister_net_sysctl_table+0x15/0x20 net/sysctl_net.c:175 __addrconf_sysctl_unregister net/ipv6/addrconf.c:7196 [inline] addrconf_sysctl_unregister net/ipv6/addrconf.c:7224 [inline] addrconf_ifdown+0x15c4/0x1910 net/ipv6/addrconf.c:3976 addrconf_notify+0x39f/0xe40 net/ipv6/addrconf.c:-1 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0x90/0x100 kernel/notifier.c:455 call_netdevice_notifiers_info net/core/dev.c:1978 [inline] call_netdevice_notifiers_extack net/core/dev.c:2016 [inline] call_netdevice_notifiers net/core/dev.c:2030 [inline] unregister_netdevice_many+0xf71/0x17f0 net/core/dev.c:10908 default_device_exit_batch+0x9ab/0xa40 net/core/dev.c:11421 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x5fd/0xad0 net/core/net_namespace.c:604 process_one_work+0x70e/0xc20 kernel/workqueue.c:2299 worker_thread+0xa29/0x11f0 kernel/workqueue.c:2446 kthread+0x270/0x310 kernel/kthread.c:386 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 The buggy address belongs to the object at ffff888121b7f000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 869 bytes inside of 2048-byte region [ffff888121b7f000, ffff888121b7f800) The buggy address belongs to the physical page: page:ffffea000486de00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888121b79000 pfn:0x121b78 head:ffffea000486de00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head|zone=1) raw: 4000000000010200 ffffea00044a2e08 ffffea0004657608 ffff888100043200 raw: ffff888121b79000 0000000000080004 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 1875, tgid 1875 (syz-executor), ts 183055336681, free_ts 182763825566 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2637 prep_new_page+0x1c/0x110 mm/page_alloc.c:2644 get_page_from_freelist+0x2c6e/0x2ce0 mm/page_alloc.c:4539 __alloc_pages+0x19e/0x3a0 mm/page_alloc.c:5837 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1 allocate_slab mm/slub.c:1962 [inline] new_slab+0x98/0x3d0 mm/slub.c:2015 ___slab_alloc+0x6f6/0xb50 mm/slub.c:3203 __slab_alloc+0x5e/0xa0 mm/slub.c:3302 slab_alloc_node mm/slub.c:3387 [inline] __kmem_cache_alloc_node+0x203/0x2b0 mm/slub.c:3462 kmalloc_trace+0x29/0xb0 mm/slab_common.c:1028 kmalloc include/linux/slab.h:563 [inline] rtnl_newlink+0xe7/0x1fc0 net/core/rtnetlink.c:3648 rtnetlink_rcv_msg+0x9d8/0xcd0 net/core/rtnetlink.c:6150 netlink_rcv_skb+0x1de/0x420 net/netlink/af_netlink.c:2503 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:6168 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline] netlink_unicast+0x89f/0xa20 net/netlink/af_netlink.c:1338 netlink_sendmsg+0x8aa/0xbc0 net/netlink/af_netlink.c:1860 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1545 [inline] free_pcp_prepare mm/page_alloc.c:1619 [inline] free_unref_page_prepare+0x742/0x750 mm/page_alloc.c:3581 free_unref_page+0x8f/0x530 mm/page_alloc.c:3677 free_the_page mm/page_alloc.c:830 [inline] __free_pages+0x67/0x100 mm/page_alloc.c:5926 __free_slab+0xca/0x1a0 mm/slub.c:2039 free_slab mm/slub.c:2054 [inline] discard_slab mm/slub.c:2060 [inline] __unfreeze_partials+0x160/0x190 mm/slub.c:2609 put_cpu_partial+0xa9/0x100 mm/slub.c:2685 __slab_free+0x1c4/0x280 mm/slub.c:3563 do_slab_free mm/slub.c:3640 [inline] ___cache_free+0xbf/0xd0 mm/slub.c:3696 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0xc6/0x140 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x14a/0x170 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x24/0x80 mm/kasan/common.c:310 kasan_slab_alloc include/linux/kasan.h:202 [inline] slab_post_alloc_hook+0x4f/0x2c0 mm/slab.h:768 slab_alloc_node mm/slub.c:3421 [inline] slab_alloc mm/slub.c:3431 [inline] __kmem_cache_alloc_lru mm/slub.c:3438 [inline] kmem_cache_alloc+0x16e/0x310 mm/slub.c:3447 getname_flags+0xb9/0x500 fs/namei.c:139 vfs_fstatat fs/stat.c:266 [inline] __do_sys_newfstatat fs/stat.c:437 [inline] __se_sys_newfstatat+0xdf/0x380 fs/stat.c:431 __x64_sys_newfstatat+0x9b/0xb0 fs/stat.c:431 Memory state around the buggy address: ffff888121b7f200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888121b7f280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888121b7f300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888121b7f380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888121b7f400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== EXT4-fs error (device loop5): htree_dirblock_to_tree:1112: inode #2: block 20: comm syz-executor: bad entry in directory: inode out of bounds - offset=1024, inode=2033530174, rec_len=1012, size=1024 fake=0 EXT4-fs error (device loop5): htree_dirblock_to_tree:1112: inode #2: block 20: comm syz-executor: bad entry in directory: inode out of bounds - offset=1024, inode=2033530174, rec_len=1012, size=1024 fake=0 EXT4-fs error (device loop5): htree_dirblock_to_tree:1112: inode #2: block 20: comm syz-executor: bad entry in directory: inode out of bounds - offset=1024, inode=2033530174, rec_len=1012, size=1024 fake=0 EXT4-fs error (device loop5): htree_dirblock_to_tree:1112: inode #2: block 20: comm syz-executor: bad entry in directory: inode out of bounds - offset=1024, inode=2033530174, rec_len=1012, size=1024 fake=0 EXT4-fs error (device loop5): htree_dirblock_to_tree:1112: inode #2: block 20: comm syz-executor: bad entry in directory: inode out of bounds - offset=1024, inode=2033530174, rec_len=1012, size=1024 fake=0 EXT4-fs error (device loop5): htree_dirblock_to_tree:1112: inode #2: block 20: comm syz-executor: bad entry in directory: inode out of bounds - offset=1024, inode=2033530174, rec_len=1012, size=1024 fake=0 EXT4-fs error (device loop5): htree_dirblock_to_tree:1112: inode #2: block 20: comm syz-executor: bad entry in directory: inode out of bounds - offset=1024, inode=2033530174, rec_len=1012, size=1024 fake=0 EXT4-fs (loop5): unmounting filesystem.