loop0: detected capacity change from 0 to 1024 ======================================================= WARNING: The mand mount option has been deprecated and and is ignored by this kernel. Remove the mand option from the mount to silence this warning. ======================================================= EXT4-fs: Ignoring removed oldalloc option EXT4-fs: Ignoring removed orlov option EXT4-fs (loop0): stripe (2) is not aligned with cluster size (16), stripe is disabled EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: writeback. netlink: 44 bytes leftover after parsing attributes in process `syz.0.0'. ================================================================== BUG: KASAN: use-after-free in ext4_ext_binsearch fs/ext4/extents.c:840 [inline] BUG: KASAN: use-after-free in ext4_find_extent+0xaea/0xcc0 fs/ext4/extents.c:956 Read of size 4 at addr ffff888055c75ebc by task syz.0.0/5337 CPU: 0 UID: 0 PID: 5337 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 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+0xba/0x230 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 ext4_ext_binsearch fs/ext4/extents.c:840 [inline] ext4_find_extent+0xaea/0xcc0 fs/ext4/extents.c:956 ext4_ext_map_blocks+0x283/0x58b0 fs/ext4/extents.c:4261 ext4_map_create_blocks+0x11d/0x540 fs/ext4/inode.c:616 ext4_map_blocks+0x7cd/0x11d0 fs/ext4/inode.c:809 mpage_map_one_extent fs/ext4/inode.c:2373 [inline] mpage_map_and_submit_extent fs/ext4/inode.c:2467 [inline] ext4_do_writepages+0x22c0/0x46e0 fs/ext4/inode.c:2925 ext4_writepages+0x241/0x3b0 fs/ext4/inode.c:3019 do_writepages+0x32e/0x550 mm/page-writeback.c:2554 filemap_writeback mm/filemap.c:387 [inline] filemap_fdatawrite_range mm/filemap.c:412 [inline] filemap_write_and_wait_range+0x335/0x3f0 mm/filemap.c:684 filemap_write_and_wait include/linux/pagemap.h:65 [inline] ext4_bmap+0x1ce/0x260 fs/ext4/inode.c:3365 bmap+0xac/0xe0 fs/inode.c:2052 ioctl_fibmap fs/ioctl.c:76 [inline] file_ioctl+0x4ac/0x860 fs/ioctl.c:326 do_vfs_ioctl+0xc26/0x1530 fs/ioctl.c:576 __do_sys_ioctl fs/ioctl.c:595 [inline] __se_sys_ioctl+0x82/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1262b9c799 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:00007f12639e5fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f1262e15fa0 RCX: 00007f1262b9c799 RDX: 0000200000000080 RSI: 0000000000000001 RDI: 0000000000000004 RBP: 00007f1262c32bd9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f1262e16038 R14: 00007f1262e15fa0 R15: 00007ffd386018c8 The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x2ba pfn:0x55c75 flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff) raw: 04fff00000000000 ffffea0001571d08 ffffea0001571d88 0000000000000000 raw: 00000000000002ba 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 5337, tgid 5336 (syz.0.0), ts 153355132988, free_ts 153659074373 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x231/0x280 mm/page_alloc.c:1889 prep_new_page mm/page_alloc.c:1897 [inline] get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3962 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5250 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2484 folio_alloc_mpol_noprof+0x39/0x70 mm/mempolicy.c:2503 shmem_alloc_folio mm/shmem.c:1930 [inline] shmem_alloc_and_add_folio+0x445/0xf80 mm/shmem.c:1972 shmem_get_folio_gfp+0x5a9/0x1670 mm/shmem.c:2567 shmem_get_folio mm/shmem.c:2673 [inline] shmem_write_begin+0x16c/0x330 mm/shmem.c:3327 generic_perform_write+0x2e2/0x8f0 mm/filemap.c:4319 shmem_file_write_iter+0xf8/0x120 mm/shmem.c:3502 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x61d/0xb90 fs/read_write.c:688 ksys_write+0x150/0x270 fs/read_write.c:740 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 5337 tgid 5336 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1433 [inline] free_unref_folios+0xed5/0x16d0 mm/page_alloc.c:3040 folios_put_refs+0x789/0x8d0 mm/swap.c:1002 folio_batch_release include/linux/pagevec.h:101 [inline] shmem_undo_range+0x52c/0x1660 mm/shmem.c:1149 shmem_truncate_range mm/shmem.c:1277 [inline] shmem_evict_inode+0x240/0x9e0 mm/shmem.c:1407 evict+0x61e/0xb10 fs/inode.c:846 __dentry_kill+0x1a2/0x5e0 fs/dcache.c:670 finish_dput+0xc9/0x480 fs/dcache.c:879 __fput+0x691/0xa70 fs/file_table.c:477 fput_close_sync+0x11f/0x240 fs/file_table.c:574 __do_sys_close fs/open.c:1509 [inline] __se_sys_close fs/open.c:1494 [inline] __x64_sys_close+0x7e/0x110 fs/open.c:1494 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888055c75d80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888055c75e00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888055c75e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888055c75f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888055c75f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================