loop0: detected capacity change from 0 to 2048 EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none. process 'syz.0.0' launched './file0' with NULL argv: empty string added loop0: detected capacity change from 2048 to 2045 ================================================================== BUG: KASAN: use-after-free in ext4_read_inline_data+0x1d0/0x2c0 fs/ext4/inline.c:214 Read of size 68 at addr ffff88805461c810 by task syz.0.0/5339 CPU: 0 UID: 0 PID: 5339 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x2b0/0x2c0 mm/kasan/generic.c:200 __asan_memcpy+0x29/0x70 mm/kasan/shadow.c:105 ext4_read_inline_data+0x1d0/0x2c0 fs/ext4/inline.c:214 ext4_read_inline_dir+0x2b3/0xb80 fs/ext4/inline.c:1405 ext4_readdir+0x3e8/0x3e90 fs/ext4/dir.c:162 iterate_dir+0x399/0x570 fs/readdir.c:108 __do_sys_getdents64 fs/readdir.c:410 [inline] __se_sys_getdents64+0xe4/0x260 fs/readdir.c:396 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f9646f8f7c9 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f9647e69038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9 RAX: ffffffffffffffda RBX: 00007f96471e5fa0 RCX: 00007f9646f8f7c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 00007f9647013f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f96471e6038 R14: 00007f96471e5fa0 R15: 00007ffce1ae83d8 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xa02 pfn:0x5461c flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff) raw: 04fff00000000000 ffffea00015186c8 ffffea0001518748 0000000000000000 raw: 0000000000000a02 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Movable, gfp_mask 0x140cca(GFP_HIGHUSER_MOVABLE|__GFP_COMP), pid 5339, tgid 5338 (syz.0.0), ts 76212734613, free_ts 76335690241 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x234/0x290 mm/page_alloc.c:1857 prep_new_page mm/page_alloc.c:1865 [inline] get_page_from_freelist+0x24e0/0x2580 mm/page_alloc.c:3915 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5210 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486 folio_alloc_mpol_noprof+0x39/0x70 mm/mempolicy.c:2505 shmem_alloc_folio mm/shmem.c:1890 [inline] shmem_alloc_and_add_folio+0x423/0xf40 mm/shmem.c:1932 shmem_get_folio_gfp+0x59d/0x1660 mm/shmem.c:2556 shmem_get_folio mm/shmem.c:2662 [inline] shmem_write_begin+0x16c/0x330 mm/shmem.c:3315 generic_perform_write+0x2c5/0x900 mm/filemap.c:4314 shmem_file_write_iter+0xf8/0x120 mm/shmem.c:3490 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x5c9/0xb30 fs/read_write.c:686 ksys_write+0x145/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 5339 tgid 5338 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1406 [inline] free_unref_folios+0xdb3/0x14f0 mm/page_alloc.c:3000 folios_put_refs+0x584/0x670 mm/swap.c:1002 folio_batch_release include/linux/pagevec.h:101 [inline] shmem_undo_range+0x49e/0x1490 mm/shmem.c:1137 shmem_truncate_range mm/shmem.c:1249 [inline] shmem_evict_inode+0x26e/0xa70 mm/shmem.c:1379 evict+0x5f4/0xae0 fs/inode.c:837 __dentry_kill+0x209/0x660 fs/dcache.c:670 finish_dput+0xc9/0x480 fs/dcache.c:879 __fput+0x68e/0xa70 fs/file_table.c:476 fput_close_sync+0x113/0x220 fs/file_table.c:573 __do_sys_close fs/open.c:1573 [inline] __se_sys_close fs/open.c:1558 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1558 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff88805461c700: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88805461c780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff88805461c800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88805461c880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88805461c900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================