================================================================== BUG: KASAN: slab-out-of-bounds in ext4_htree_fill_tree+0x106b/0x10d0 fs/ext4/namei.c:1246 Read of size 1 at addr ffff88810f815535 by task syz-executor/470 CPU: 1 PID: 470 Comm: syz-executor Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:88 dump_stack_lvl+0xee/0x150 lib/dump_stack.c:106 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:427 [inline] kasan_report+0xf1/0x140 mm/kasan/report.c:444 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report_generic.c:306 ext4_htree_fill_tree+0x106b/0x10d0 fs/ext4/namei.c:1246 ext4_dx_readdir fs/ext4/dir.c:609 [inline] ext4_readdir+0x2bfd/0x3a40 fs/ext4/dir.c:145 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+0x592/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:218 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f2cea56aad3 Code: c1 66 0f 1f 44 00 00 48 83 c4 08 48 89 ef 5b 5d e9 72 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:00007fff2a63af08 EFLAGS: 00000293 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 0000555562e104e0 RCX: 00007f2cea56aad3 RDX: 0000000000008000 RSI: 0000555562e104e0 RDI: 0000000000000005 RBP: 0000555562e104b4 R08: 0000000000028b61 R09: 0000000000000000 R10: 00007f2cea727ca0 R11: 0000000000000293 R12: ffffffffffffffa8 R13: 0000000000000010 R14: 0000555562e104b0 R15: 00007fff2a63d1c0 Allocated by task 361: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:433 [inline] ____kasan_kmalloc mm/kasan/common.c:512 [inline] __kasan_kmalloc+0xda/0x110 mm/kasan/common.c:521 kasan_kmalloc include/linux/kasan.h:227 [inline] __kmalloc_track_caller+0x13c/0x2c0 mm/slub.c:4954 kmalloc_reserve net/core/skbuff.c:357 [inline] __alloc_skb+0x21a/0x740 net/core/skbuff.c:428 alloc_skb include/linux/skbuff.h:1183 [inline] nlmsg_new include/net/netlink.h:953 [inline] rtmsg_ifinfo_build_skb+0x7c/0x180 net/core/rtnetlink.c:3884 rtmsg_ifinfo_event net/core/rtnetlink.c:3920 [inline] rtmsg_ifinfo+0x7a/0x130 net/core/rtnetlink.c:3929 __dev_notify_flags+0xdb/0x500 net/core/dev.c:8895 dev_change_flags+0xe8/0x1a0 net/core/dev.c:8937 do_setlink+0xbed/0x3990 net/core/rtnetlink.c:2779 __rtnl_newlink net/core/rtnetlink.c:3450 [inline] rtnl_newlink+0x13fa/0x17b0 net/core/rtnetlink.c:3572 rtnetlink_rcv_msg+0x9e4/0xb90 net/core/rtnetlink.c:5650 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2511 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5668 netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline] netlink_unicast+0x876/0xa40 net/netlink/af_netlink.c:1348 netlink_sendmsg+0x86a/0xb70 net/netlink/af_netlink.c:1922 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] __sys_sendto+0x423/0x580 net/socket.c:2063 __do_sys_sendto net/socket.c:2075 [inline] __se_sys_sendto net/socket.c:2071 [inline] __x64_sys_sendto+0xe5/0x100 net/socket.c:2071 x64_sys_call+0x178/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Freed by task 361: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4a/0x70 mm/kasan/common.c:45 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370 ____kasan_slab_free+0x125/0x160 mm/kasan/common.c:365 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:373 kasan_slab_free include/linux/kasan.h:193 [inline] slab_free_hook mm/slub.c:1723 [inline] slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1749 slab_free mm/slub.c:3521 [inline] kfree+0xc4/0x270 mm/slub.c:4583 skb_free_head net/core/skbuff.c:656 [inline] pskb_expand_head+0x36c/0x11d0 net/core/skbuff.c:1766 netlink_trim+0x193/0x230 net/netlink/af_netlink.c:1303 netlink_broadcast_filtered+0x78/0x1230 net/netlink/af_netlink.c:1515 netlink_broadcast net/netlink/af_netlink.c:1560 [inline] nlmsg_multicast include/net/netlink.h:1033 [inline] nlmsg_notify+0xed/0x1b0 net/netlink/af_netlink.c:2554 rtnl_notify net/core/rtnetlink.c:759 [inline] rtmsg_ifinfo_send net/core/rtnetlink.c:3908 [inline] rtmsg_ifinfo_event net/core/rtnetlink.c:3923 [inline] rtmsg_ifinfo+0xea/0x130 net/core/rtnetlink.c:3929 __dev_notify_flags+0xdb/0x500 net/core/dev.c:8895 dev_change_flags+0xe8/0x1a0 net/core/dev.c:8937 do_setlink+0xbed/0x3990 net/core/rtnetlink.c:2779 __rtnl_newlink net/core/rtnetlink.c:3450 [inline] rtnl_newlink+0x13fa/0x17b0 net/core/rtnetlink.c:3572 rtnetlink_rcv_msg+0x9e4/0xb90 net/core/rtnetlink.c:5650 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2511 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5668 netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline] netlink_unicast+0x876/0xa40 net/netlink/af_netlink.c:1348 netlink_sendmsg+0x86a/0xb70 net/netlink/af_netlink.c:1922 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] __sys_sendto+0x423/0x580 net/socket.c:2063 __do_sys_sendto net/socket.c:2075 [inline] __se_sys_sendto net/socket.c:2071 [inline] __x64_sys_sendto+0xe5/0x100 net/socket.c:2071 x64_sys_call+0x178/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff88810f814000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 1333 bytes to the right of 4096-byte region [ffff88810f814000, ffff88810f815000) The buggy address belongs to the page: page:ffffea00043e0400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10f810 head:ffffea00043e0400 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head|zone=1) raw: 4000000000010200 dead000000000100 dead000000000122 ffff888100043380 raw: 0000000000000000 0000000000040004 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 102, ts 4669813300, free_ts 0 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2605 prep_new_page+0x1c/0x110 mm/page_alloc.c:2611 get_page_from_freelist+0x2cc5/0x2d50 mm/page_alloc.c:4485 __alloc_pages+0x18f/0x440 mm/page_alloc.c:5795 alloc_slab_page mm/slub.c:-1 [inline] allocate_slab mm/slub.c:1932 [inline] new_slab+0xa1/0x4d0 mm/slub.c:1995 ___slab_alloc+0x381/0x810 mm/slub.c:3028 __slab_alloc+0x49/0x90 mm/slub.c:3115 slab_alloc_node mm/slub.c:3206 [inline] slab_alloc mm/slub.c:3250 [inline] kmem_cache_alloc_trace+0x146/0x270 mm/slub.c:3267 kmalloc include/linux/slab.h:616 [inline] kzalloc include/linux/slab.h:747 [inline] kobject_uevent_env+0x272/0x700 lib/kobject_uevent.c:539 kobject_synth_uevent+0x520/0xaf0 lib/kobject_uevent.c:208 store_uevent+0x16/0x30 kernel/module.c:1172 module_attr_store+0x5f/0x80 kernel/params.c:919 sysfs_kf_write+0x129/0x150 fs/sysfs/file.c:139 kernfs_fop_write_iter+0x2c5/0x400 fs/kernfs/file.c:296 call_write_iter include/linux/fs.h:2212 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0x802/0xf70 fs/read_write.c:594 ksys_write+0x140/0x240 fs/read_write.c:647 page_owner free stack trace missing Memory state around the buggy address: ffff88810f815400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88810f815480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88810f815500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88810f815580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88810f815600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================