NFS: abort nfs_atomic_open_v23 if name is too long.

An attempt to open a file with a name longer than NFS3_MAXNAMLEN will
trigger a WARN_ON_ONCE in encode_filename3() because
nfs_atomic_open_v23() doesn't have the test on ->d_name.len that
nfs_atomic_open() has.

So add that test.

Reported-by: James Clark <james.clark@arm.com>
Closes: https://lore.kernel.org/all/20240528105249.69200-1-james.clark@arm.com/
Fixes: 7c6c5249f0 ("NFS: add atomic_open for NFSv3 to handle O_TRUNC correctly.")
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
This commit is contained in:
NeilBrown 2024-05-29 09:11:36 +10:00 committed by Trond Myklebust
parent 0c8c7c5597
commit 296f4ce81d

View File

@ -2254,6 +2254,9 @@ int nfs_atomic_open_v23(struct inode *dir, struct dentry *dentry,
*/
int error = 0;
if (dentry->d_name.len > NFS_SERVER(dir)->namelen)
return -ENAMETOOLONG;
if (open_flags & O_CREAT) {
file->f_mode |= FMODE_CREATED;
error = nfs_do_create(dir, dentry, mode, open_flags);