diff options
| author | Trond Myklebust <trond.myklebust@hammerspace.com> | 2025-07-22 09:24:58 -0400 |
|---|---|---|
| committer | Trond Myklebust <trond.myklebust@hammerspace.com> | 2025-07-22 09:50:56 -0400 |
| commit | ef93a685e01a281b5e2a25ce4e3428cf9371a205 (patch) | |
| tree | 1c4118d7e02018a73e547920bb08c986f709ba22 | |
| parent | f66e6bffc531bafaeb067e6f6af56f52d5cd4ac2 (diff) | |
NFS: Fix filehandle bounds checking in nfs_fh_to_dentry()
The function needs to check the minimal filehandle length before it can
access the embedded filehandle.
Reported-by: zhangjian <zhangjian496@huawei.com>
Fixes: 20fa19027286 ("nfs: add export operations")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
| -rw-r--r-- | fs/nfs/export.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/fs/nfs/export.c b/fs/nfs/export.c index e9c233b6fd20..a10dd5f9d078 100644 --- a/fs/nfs/export.c +++ b/fs/nfs/export.c @@ -66,14 +66,21 @@ nfs_fh_to_dentry(struct super_block *sb, struct fid *fid, { struct nfs_fattr *fattr = NULL; struct nfs_fh *server_fh = nfs_exp_embedfh(fid->raw); - size_t fh_size = offsetof(struct nfs_fh, data) + server_fh->size; + size_t fh_size = offsetof(struct nfs_fh, data); const struct nfs_rpc_ops *rpc_ops; struct dentry *dentry; struct inode *inode; - int len = EMBED_FH_OFF + XDR_QUADLEN(fh_size); + int len = EMBED_FH_OFF; u32 *p = fid->raw; int ret; + /* Initial check of bounds */ + if (fh_len < len + XDR_QUADLEN(fh_size) || + fh_len > XDR_QUADLEN(NFS_MAXFHSIZE)) + return NULL; + /* Calculate embedded filehandle size */ + fh_size += server_fh->size; + len += XDR_QUADLEN(fh_size); /* NULL translates to ESTALE */ if (fh_len < len || fh_type != len) return NULL; |