syzbot


KASAN: use-after-free Read in reiserfs_fill_super (2)

Status: auto-closed as invalid on 2022/02/03 07:30
Reported-by: syzbot+66c88846eb5fa7a16641@syzkaller.appspotmail.com
First crash: 367d, last: 367d
similar bugs (2):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: use-after-free Read in reiserfs_fill_super C error done 2 731d 730d 21/24 fixed on 2021/03/10 01:48
linux-4.14 KASAN: use-after-free Read in reiserfs_fill_super C done 2 700d 700d 1/1 fixed on 2021/02/21 17:18

Sample crash report:
==================================================================
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
==================================================================

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-linux-next-kasan-gce-root 2021/12/05 07:29 linux-next f81e94e91878 a617004c .config log report info KASAN: use-after-free Read in reiserfs_fill_super
* Struck through repros no longer work on HEAD.