From 296f4ce81d08e73c22408c49f4938a85bd075e5c Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Wed, 29 May 2024 09:11:36 +1000 Subject: [PATCH] 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 Closes: https://lore.kernel.org/all/20240528105249.69200-1-james.clark@arm.com/ Fixes: 7c6c5249f061 ("NFS: add atomic_open for NFSv3 to handle O_TRUNC correctly.") Signed-off-by: NeilBrown Reviewed-by: Christoph Hellwig Signed-off-by: Trond Myklebust --- fs/nfs/dir.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index 788077a4feb9..2b68a14982c8 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -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);