EXT4-fs (loop2): mounted filesystem without journal. Opts: block_validity,bsddf,nombcache,inode_readahead_blks=0x0000000000000000,debug_want_extra_isize=0x0000000000000080,orlov,nogrpid,noauto_da_alloc,grpjquota=,,errors=continue. Quota mode: none. ================================================================== BUG: KASAN: use-after-free in xattr_find_entry fs/ext4/xattr.c:294 [inline] BUG: KASAN: use-after-free in ext4_xattr_ibody_get+0x62e/0x690 fs/ext4/xattr.c:601 Read of size 4 at addr ffff88810c8dc004 by task syz.2.18/375 CPU: 0 PID: 375 Comm: syz.2.18 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:88 dump_stack_lvl+0x110/0x170 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_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308 xattr_find_entry fs/ext4/xattr.c:294 [inline] ext4_xattr_ibody_get+0x62e/0x690 fs/ext4/xattr.c:601 ext4_xattr_get+0x116/0x820 fs/ext4/xattr.c:655 ext4_get_acl+0x85/0x670 fs/ext4/acl.c:165 get_acl+0x161/0x270 fs/posix_acl.c:153 posix_acl_chmod+0xe9/0x250 fs/posix_acl.c:602 ext4_setattr+0xb23/0x1ac0 fs/ext4/inode.c:5672 notify_change+0xbca/0xe90 fs/attr.c:505 chmod_common+0x223/0x3c0 fs/open.c:583 do_fchmodat+0xd4/0x1a0 fs/open.c:622 __do_sys_fchmodat fs/open.c:635 [inline] __se_sys_fchmodat fs/open.c:632 [inline] __x64_sys_fchmodat+0x7b/0x90 fs/open.c:632 x64_sys_call+0x1b7/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:269 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: 0033:0x7fcc16012e59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffe12da6208 EFLAGS: 00000246 ORIG_RAX: 000000000000010c RAX: ffffffffffffffda RBX: 00007fcc1628bfa0 RCX: 00007fcc16012e59 RDX: 000000000000017f RSI: 0000200000000300 RDI: ffffffffffffff9c RBP: 00007fcc160a8d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fcc1628bfac R14: 00007fcc1628bfa0 R15: 00007fcc1628bfa0 The buggy address belongs to the page: page:ffffea0004323700 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10c8dc flags: 0x4000000000000000(zone=1) raw: 4000000000000000 ffffea0004323748 ffffea0004b2ee48 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Unmovable, gfp_mask 0x500dc0(GFP_USER|__GFP_ZERO|__GFP_ACCOUNT), pid 323, ts 25773759575, free_ts 25780491821 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+0x2d3a/0x2dc0 mm/page_alloc.c:4485 __alloc_pages+0x1a2/0x460 mm/page_alloc.c:5822 __alloc_pages_node include/linux/gfp.h:595 [inline] alloc_pages_node include/linux/gfp.h:609 [inline] alloc_pages include/linux/gfp.h:622 [inline] __pte_alloc_one include/asm-generic/pgalloc.h:63 [inline] pte_alloc_one+0x70/0x190 arch/x86/mm/pgtable.c:33 __pte_alloc+0x75/0x2a0 mm/memory.c:504 copy_pte_range mm/memory.c:1098 [inline] copy_pmd_range mm/memory.c:1233 [inline] copy_pud_range mm/memory.c:1270 [inline] copy_p4d_range mm/memory.c:1294 [inline] copy_page_range+0x237c/0x28d0 mm/memory.c:1367 dup_mmap kernel/fork.c:663 [inline] dup_mm kernel/fork.c:1527 [inline] copy_mm+0xbf2/0x13c0 kernel/fork.c:1579 copy_process+0x117c/0x3250 kernel/fork.c:2353 kernel_clone+0x233/0x960 kernel/fork.c:2742 __do_sys_clone kernel/fork.c:2868 [inline] __se_sys_clone kernel/fork.c:2852 [inline] __x64_sys_clone+0x198/0x210 kernel/fork.c:2852 x64_sys_call+0x41f/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:57 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 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1472 [inline] free_pcp_prepare mm/page_alloc.c:1544 [inline] free_unref_page_prepare+0x542/0x550 mm/page_alloc.c:3534 free_unref_page_list+0x13a/0x9d0 mm/page_alloc.c:3671 release_pages+0x1279/0x12e0 mm/swap.c:1015 free_pages_and_swap_cache+0x86/0xa0 mm/swap_state.c:320 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline] tlb_flush_mmu_free mm/mmu_gather.c:240 [inline] tlb_flush_mmu mm/mmu_gather.c:247 [inline] tlb_finish_mmu+0x17e/0x310 mm/mmu_gather.c:338 exit_mmap+0x43b/0x8b0 mm/mmap.c:3248 __mmput+0x93/0x320 kernel/fork.c:1185 mmput+0x50/0x150 kernel/fork.c:1208 exit_mm kernel/exit.c:555 [inline] do_exit+0xa89/0x2890 kernel/exit.c:877 do_group_exit+0x141/0x310 kernel/exit.c:1004 get_signal+0x66a/0x1480 kernel/signal.c:2907 arch_do_signal_or_restart+0xdf/0x11c0 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0xa7/0xe0 kernel/entry/common.c:178 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 Memory state around the buggy address: ffff88810c8dbf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88810c8dbf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88810c8dc000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88810c8dc080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88810c8dc100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================