Hello, syzbot found the following issue on: HEAD commit: 40f71e7cd3c6 Merge tag 'net-6.4-rc7' of git://git.kernel.o.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=150f9b7f280000 kernel config: https://syzkaller.appspot.com/x/.config?x=7ff8f87c7ab0e04e dashboard link: https://syzkaller.appspot.com/bug?extid=b7d8a575b4546d334d73 compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/2dc89d5fee38/disk-40f71e7c.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/0ced5a475218/vmlinux-40f71e7c.xz kernel image: https://storage.googleapis.com/syzbot-assets/d543a4f69684/bzImage-40f71e7c.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+b7d8a575b4546d334d73@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: use-after-free in leaf_copy_items fs/reiserfs/lbalance.c:617 [inline] BUG: KASAN: use-after-free in leaf_move_items+0x1fbb/0x2960 fs/reiserfs/lbalance.c:726 Read of size 2 at addr ffff8880429f6ffe by task syz-executor.3/11849 CPU: 0 PID: 11849 Comm: syz-executor.3 Not tainted 6.4.0-rc6-syzkaller-00195-g40f71e7cd3c6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:351 [inline] print_report+0x163/0x540 mm/kasan/report.c:462 kasan_report+0x176/0x1b0 mm/kasan/report.c:572 leaf_copy_items fs/reiserfs/lbalance.c:617 [inline] leaf_move_items+0x1fbb/0x2960 fs/reiserfs/lbalance.c:726 balance_leaf_new_nodes_paste_whole fs/reiserfs/do_balan.c:1162 [inline] balance_leaf_new_nodes_paste fs/reiserfs/do_balan.c:1215 [inline] balance_leaf_new_nodes fs/reiserfs/do_balan.c:1246 [inline] balance_leaf+0x6519/0x12510 fs/reiserfs/do_balan.c:1450 do_balance+0x30d/0x8f0 fs/reiserfs/do_balan.c:1888 reiserfs_paste_into_item+0x732/0x870 fs/reiserfs/stree.c:2157 reiserfs_get_block+0x2250/0x5130 fs/reiserfs/inode.c:1069 __block_write_begin_int+0x548/0x1a50 fs/buffer.c:2064 reiserfs_write_begin+0x24d/0x520 fs/reiserfs/inode.c:2773 generic_cont_expand_simple+0x18b/0x2a0 fs/buffer.c:2425 reiserfs_setattr+0x57d/0x1140 fs/reiserfs/inode.c:3303 notify_change+0xc8b/0xf40 fs/attr.c:483 do_truncate+0x220/0x300 fs/open.c:66 do_sys_ftruncate+0x2e4/0x380 fs/open.c:194 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f6e7688c389 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f6e7763e168 EFLAGS: 00000246 ORIG_RAX: 000000000000004d RAX: ffffffffffffffda RBX: 00007f6e769abf80 RCX: 00007f6e7688c389 RDX: 0000000000000000 RSI: 0000000002007fff RDI: 0000000000000008 RBP: 00007f6e768d7493 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff25fd51bf R14: 00007f6e7763e300 R15: 0000000000022000 </TASK> The buggy address belongs to the physical page: page:ffffea00010a7d80 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x429f6 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000000 ffffea00010a7808 ffffea00010a7d48 0000000000000000 raw: 0000000000000001 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 11767, tgid 11766 (syz-executor.5), ts 1715307232613, free_ts 1718076484344 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1731 prep_new_page mm/page_alloc.c:1738 [inline] get_page_from_freelist+0x321c/0x33a0 mm/page_alloc.c:3502 __alloc_pages+0x255/0x670 mm/page_alloc.c:4768 __folio_alloc+0x13/0x30 mm/page_alloc.c:4800 vma_alloc_folio+0x48a/0x9a0 mm/mempolicy.c:2240 shmem_alloc_folio mm/shmem.c:1579 [inline] shmem_alloc_and_acct_folio+0x5e7/0xe10 mm/shmem.c:1603 shmem_get_folio_gfp+0x120f/0x3470 mm/shmem.c:1948 shmem_get_folio mm/shmem.c:2079 [inline] shmem_write_begin+0x172/0x4e0 mm/shmem.c:2573 generic_perform_write+0x300/0x5e0 mm/filemap.c:3929 __generic_file_write_iter+0x17a/0x400 mm/filemap.c:4057 generic_file_write_iter+0xaf/0x310 mm/filemap.c:4089 call_write_iter include/linux/fs.h:1868 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x790/0xb20 fs/read_write.c:584 ksys_write+0x1a0/0x2c0 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1302 [inline] free_unref_page_prepare+0x903/0xa30 mm/page_alloc.c:2564 free_unref_page_list+0x596/0x830 mm/page_alloc.c:2705 release_pages+0x2193/0x2470 mm/swap.c:1042 __pagevec_release+0x84/0x100 mm/swap.c:1062 pagevec_release include/linux/pagevec.h:63 [inline] folio_batch_release include/linux/pagevec.h:132 [inline] shmem_undo_range+0x6af/0x1ba0 mm/shmem.c:954 shmem_truncate_range mm/shmem.c:1049 [inline] shmem_evict_inode+0x258/0x9f0 mm/shmem.c:1164 evict+0x2a4/0x620 fs/inode.c:665 __dentry_kill+0x436/0x650 fs/dcache.c:607 dentry_kill+0xbb/0x290 dput+0x1f3/0x420 fs/dcache.c:913 __fput+0x5e4/0x890 fs/file_table.c:329 task_work_run+0x24a/0x300 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xd9/0x100 kernel/entry/common.c:171 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x64/0x280 kernel/entry/common.c:297 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86 Memory state around the buggy address: ffff8880429f6e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8880429f6f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff8880429f6f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff8880429f7000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880429f7080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== --- This report is generated by a bot. 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