Hello, syzbot found the following issue on: HEAD commit: f81e94e91878 Add linux-next specific files for 20211125 git tree: linux-next console output: https://syzkaller.appspot.com/x/log.txt?x=17f9e455b00000 kernel config: https://syzkaller.appspot.com/x/.config?x=be9183de0824e4d7 dashboard link: https://syzkaller.appspot.com/bug?extid=66c88846eb5fa7a16641 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 Unfortunately, I don't have any reproducer for this issue yet. IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+66c88846eb5fa7a16641@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: use-after-free in init_inode fs/reiserfs/inode.c:1325 [inline] BUG: KASAN: use-after-free in reiserfs_read_locked_inode+0x1e47/0x2160 fs/reiserfs/inode.c:1574 Read of size 4 at addr ffff88808189c000 by task syz-executor.5/24610 CPU: 0 PID: 24610 Comm: syz-executor.5 Not tainted 5.16.0-rc2-next-20211125-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0xa5/0x3ed mm/kasan/report.c:247 __kasan_report mm/kasan/report.c:433 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:450 init_inode fs/reiserfs/inode.c:1325 [inline] reiserfs_read_locked_inode+0x1e47/0x2160 fs/reiserfs/inode.c:1574 reiserfs_fill_super+0x1350/0x2f80 fs/reiserfs/super.c:2071 mount_bdev+0x34d/0x410 fs/super.c:1370 legacy_get_tree+0x105/0x220 fs/fs_context.c:610 vfs_get_tree+0x89/0x2f0 fs/super.c:1500 do_new_mount fs/namespace.c:2988 [inline] path_mount+0x1320/0x1fa0 fs/namespace.c:3318 do_mount fs/namespace.c:3331 [inline] __do_sys_mount fs/namespace.c:3539 [inline] __se_sys_mount fs/namespace.c:3516 [inline] __x64_sys_mount+0x27f/0x300 fs/namespace.c:3516 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f5e666f401a Code: 48 c7 c2 bc ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 b8 04 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f5e65667fa8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 00007f5e666f401a RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f5e65668000 RBP: 00007f5e65668040 R08: 00007f5e65668040 R09: 0000000020000000 R10: 0000000000200000 R11: 0000000000000206 R12: 0000000020000000 R13: 0000000020000100 R14: 00007f5e65668000 R15: 0000000020011400 </TASK> The buggy address belongs to the page: page:ffffea0002062700 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x8189c flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 ffffea0002062748 ffff8880b9c40140 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 0x1100cca(GFP_HIGHUSER_MOVABLE), pid 21718, ts 549829566702, free_ts 550946257184 prep_new_page mm/page_alloc.c:2433 [inline] get_page_from_freelist+0xa72/0x2f40 mm/page_alloc.c:4164 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5376 alloc_pages_vma+0xf3/0x7d0 mm/mempolicy.c:2153 shmem_alloc_page+0x11f/0x1f0 mm/shmem.c:1579 shmem_alloc_and_acct_page+0x161/0x10b0 mm/shmem.c:1604 shmem_getpage_gfp+0xb2d/0x23a0 mm/shmem.c:1902 shmem_fault+0x1b4/0x750 mm/shmem.c:2114 __do_fault+0x10d/0x790 mm/memory.c:3845 do_read_fault mm/memory.c:4160 [inline] do_fault mm/memory.c:4289 [inline] handle_pte_fault mm/memory.c:4547 [inline] __handle_mm_fault+0x2771/0x4170 mm/memory.c:4682 handle_mm_fault+0x1c8/0x790 mm/memory.c:4780 faultin_page mm/gup.c:939 [inline] __get_user_pages+0x522/0xfb0 mm/gup.c:1160 populate_vma_page_range+0x24d/0x330 mm/gup.c:1492 __mm_populate+0x1ea/0x3e0 mm/gup.c:1601 mm_populate include/linux/mm.h:2734 [inline] vm_mmap_pgoff+0x20e/0x290 mm/util.c:524 ksys_mmap_pgoff+0x79/0x5a0 mm/mmap.c:1629 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1351 [inline] free_pcp_prepare+0x414/0xb60 mm/page_alloc.c:1403 free_unref_page_prepare mm/page_alloc.c:3324 [inline] free_unref_page_list+0x1a9/0xfa0 mm/page_alloc.c:3440 release_pages+0x3ed/0x1b30 mm/swap.c:980 __pagevec_release+0x77/0x100 mm/swap.c:1000 pagevec_release include/linux/pagevec.h:81 [inline] shmem_undo_range+0x94e/0x1b00 mm/shmem.c:957 shmem_truncate_range mm/shmem.c:1056 [inline] shmem_evict_inode+0x3a4/0xbd0 mm/shmem.c:1138 evict+0x2ed/0x6b0 fs/inode.c:639 iput_final fs/inode.c:1719 [inline] iput.part.0+0x539/0x850 fs/inode.c:1745 iput+0x58/0x70 fs/inode.c:1735 dentry_unlink_inode+0x2b1/0x460 fs/dcache.c:376 __dentry_kill+0x3c0/0x640 fs/dcache.c:582 dentry_kill fs/dcache.c:708 [inline] dput+0x738/0xbc0 fs/dcache.c:888 __fput+0x3ab/0x9f0 fs/file_table.c:293 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 get_signal+0x1b01/0x28b0 kernel/signal.c:2628 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:868 Memory state around the buggy address: ffff88808189bf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88808189bf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88808189c000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff88808189c080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff88808189c100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== --- This report is generated by a bot. 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