[ Upstream commit 626bcf2b7ce87211dba565f2bfa7842ba5be5c1b ] As Jungyeon reported in bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=203225 - Overview When mounting the attached crafted image and unmounting it, following errors are reported. Additionally, it hangs on sync after unmounting. The image is intentionally fuzzed from a normal f2fs image for testing. Compile options for F2FS are as follows. CONFIG_F2FS_FS=y CONFIG_F2FS_STAT_FS=y CONFIG_F2FS_FS_XATTR=y CONFIG_F2FS_FS_POSIX_ACL=y CONFIG_F2FS_CHECK_FS=y - Reproduces mkdir test mount -t f2fs tmp.img test touch test/t umount test sync - Messages kernel BUG at fs/f2fs/node.c:3073! RIP: 0010:f2fs_destroy_node_manager+0x2f0/0x300 Call Trace: f2fs_put_super+0xf4/0x270 generic_shutdown_super+0x62/0x110 kill_block_super+0x1c/0x50 kill_f2fs_super+0xad/0xd0 deactivate_locked_super+0x35/0x60 cleanup_mnt+0x36/0x70 task_work_run+0x75/0x90 exit_to_usermode_loop+0x93/0xa0 do_syscall_64+0xba/0xf0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0010:f2fs_destroy_node_manager+0x2f0/0x300 NAT table is corrupted, so reserved meta/node inode ids were added into free list incorrectly, during file creation, since reserved id has cached in inode hash, so it fails the creation and preallocated nid can not be released later, result in kernel panic. To fix this issue, let's do nid boundary check during free nid loading. Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- fs/f2fs/node.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c index d45ecef75116..63bb6134d39a 100644 --- a/fs/f2fs/node.c +++ b/fs/f2fs/node.c @@ -2082,6 +2082,9 @@ static bool add_free_nid(struct f2fs_sb_info *sbi, if (unlikely(nid == 0)) return false; + if (unlikely(f2fs_check_nid_range(sbi, nid))) + return false; + i = f2fs_kmem_cache_alloc(free_nid_slab, GFP_NOFS); i->nid = nid; i->state = FREE_NID; -- 2.20.1