From: Zeng Heng zengheng4@huawei.com
[ Upstream commit ab84eee4c7ab929996602eda7832854c35a6dda2 ]
Here is a BUG report from syzbot:
BUG: KASAN: slab-out-of-bounds in hdr_delete_de+0xe0/0x150 fs/ntfs3/index.c:806 Read of size 16842960 at addr ffff888079cc0600 by task syz-executor934/3631
Call Trace: memmove+0x25/0x60 mm/kasan/shadow.c:54 hdr_delete_de+0xe0/0x150 fs/ntfs3/index.c:806 indx_delete_entry+0x74f/0x3670 fs/ntfs3/index.c:2193 ni_remove_name+0x27a/0x980 fs/ntfs3/frecord.c:2910 ntfs_unlink_inode+0x3d4/0x720 fs/ntfs3/inode.c:1712 ntfs_rename+0x41a/0xcb0 fs/ntfs3/namei.c:276
Before using the meta-data in struct INDEX_HDR, we need to check index header valid or not. Otherwise, the corruptedi (or malicious) fs image can cause out-of-bounds access which could make kernel panic.
Fixes: 82cae269cfa9 ("fs/ntfs3: Add initialization of super block") Reported-by: syzbot+9c2811fd56591639ff5f@syzkaller.appspotmail.com Signed-off-by: Zeng Heng zengheng4@huawei.com Signed-off-by: Konstantin Komarov almaz.alexandrovich@paragon-software.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/ntfs3/fslog.c | 2 +- fs/ntfs3/index.c | 4 ++++ fs/ntfs3/ntfs_fs.h | 1 + 3 files changed, 6 insertions(+), 1 deletion(-)
diff --git a/fs/ntfs3/fslog.c b/fs/ntfs3/fslog.c index dc723f03d6bb2..bf73964472845 100644 --- a/fs/ntfs3/fslog.c +++ b/fs/ntfs3/fslog.c @@ -2575,7 +2575,7 @@ static int read_next_log_rec(struct ntfs_log *log, struct lcb *lcb, u64 *lsn) return find_log_rec(log, *lsn, lcb); }
-static inline bool check_index_header(const struct INDEX_HDR *hdr, size_t bytes) +bool check_index_header(const struct INDEX_HDR *hdr, size_t bytes) { __le16 mask; u32 min_de, de_off, used, total; diff --git a/fs/ntfs3/index.c b/fs/ntfs3/index.c index ae9616becec15..7a1e01a2ed9ae 100644 --- a/fs/ntfs3/index.c +++ b/fs/ntfs3/index.c @@ -848,6 +848,10 @@ static inline struct NTFS_DE *hdr_delete_de(struct INDEX_HDR *hdr, u32 off = PtrOffset(hdr, re); int bytes = used - (off + esize);
+ /* check INDEX_HDR valid before using INDEX_HDR */ + if (!check_index_header(hdr, le32_to_cpu(hdr->total))) + return NULL; + if (off >= used || esize < sizeof(struct NTFS_DE) || bytes < sizeof(struct NTFS_DE)) return NULL; diff --git a/fs/ntfs3/ntfs_fs.h b/fs/ntfs3/ntfs_fs.h index 0e051c5595a21..2050eb3f6a5a6 100644 --- a/fs/ntfs3/ntfs_fs.h +++ b/fs/ntfs3/ntfs_fs.h @@ -579,6 +579,7 @@ int ni_rename(struct ntfs_inode *dir_ni, struct ntfs_inode *new_dir_ni, bool ni_is_dirty(struct inode *inode);
/* Globals from fslog.c */ +bool check_index_header(const struct INDEX_HDR *hdr, size_t bytes); int log_replay(struct ntfs_inode *ni, bool *initialized);
/* Globals from fsntfs.c */