================================================================== BUG: KASAN: use-after-free in ext4_xattr_list_entries+0x278/0x334 fs/ext4/xattr.c:670 Read of size 4 at addr ffff0000f526f028 by task syz.3.422/6600 CPU: 0 PID: 6600 Comm: syz.3.422 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025 Call trace: dump_backtrace+0x1c0/0x1ec arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106 print_address_description+0x88/0x218 mm/kasan/report.c:316 print_report+0x50/0x68 mm/kasan/report.c:420 kasan_report+0xa8/0xfc mm/kasan/report.c:524 __asan_report_load4_noabort+0x2c/0x38 mm/kasan/report_generic.c:350 ext4_xattr_list_entries+0x278/0x334 fs/ext4/xattr.c:670 ext4_xattr_ibody_list fs/ext4/xattr.c:740 [inline] ext4_listxattr+0x1a8/0x4e8 fs/ext4/xattr.c:765 vfs_listxattr fs/xattr.c:457 [inline] listxattr+0x29c/0x3cc fs/xattr.c:804 path_listxattr+0xe0/0x1b8 fs/xattr.c:828 __do_sys_listxattr fs/xattr.c:840 [inline] __se_sys_listxattr fs/xattr.c:837 [inline] __arm64_sys_listxattr+0x80/0x94 fs/xattr.c:837 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 Allocated by task 4848: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:53 kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:505 __kasan_slab_alloc+0x70/0x88 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x74/0x430 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] kmem_cache_alloc_node+0x250/0x33c mm/slub.c:3404 __alloc_skb+0x128/0x714 net/core/skbuff.c:505 alloc_skb include/linux/skbuff.h:1271 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline] nsim_dev_trap_report_work+0x214/0x984 drivers/net/netdevsim/dev.c:851 process_one_work+0x7f8/0x13a4 kernel/workqueue.c:2292 worker_thread+0x8c4/0xfec kernel/workqueue.c:2439 kthread+0x250/0x2d8 kernel/kthread.c:376 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:850 The buggy address belongs to the object at ffff0000f526f000 which belongs to the cache skbuff_head_cache of size 240 The buggy address is located 40 bytes inside of 240-byte region [ffff0000f526f000, ffff0000f526f0f0) The buggy address belongs to the physical page: page:0000000098d7897d refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff0000f526f000 pfn:0x13526f flags: 0x5ffc00000000200(slab|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000000200 fffffc00035475c8 fffffc0003c590c8 ffff0000c086c180 raw: ffff0000f526f000 00000000000c0004 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000f526ef00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff0000f526ef80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff0000f526f000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000f526f080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ffff0000f526f100: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ================================================================== netlink: 52 bytes leftover after parsing attributes in process `syz.3.422'.