From 898f94465205e33295c29333a82a249b8f90aa74 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Thu, 23 Oct 2025 09:12:39 -0400 Subject: lockd: don't allow locking on reexported NFSv2/3 Since commit 9254c8ae9b81 ("nfsd: disallow file locking and delegations for NFSv4 reexport"), file locking when reexporting an NFS mount via NFSv4 is expressly prohibited by nfsd. Do the same in lockd: Add a new nlmsvc_file_cannot_lock() helper that will test whether file locking is allowed for a given file, and return nlm_lck_denied_nolocks if it isn't. Signed-off-by: Jeff Layton Tested-by: Olga Kornievskaia Signed-off-by: Chuck Lever --- include/linux/lockd/lockd.h | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) (limited to 'include/linux/lockd') diff --git a/include/linux/lockd/lockd.h b/include/linux/lockd/lockd.h index c8f0f9458f2c..330e38776bb2 100644 --- a/include/linux/lockd/lockd.h +++ b/include/linux/lockd/lockd.h @@ -12,6 +12,7 @@ /* XXX: a lot of this should really be under fs/lockd. */ +#include #include #include #include @@ -307,7 +308,7 @@ void nlmsvc_invalidate_all(void); int nlmsvc_unlock_all_by_sb(struct super_block *sb); int nlmsvc_unlock_all_by_ip(struct sockaddr *server_addr); -static inline struct file *nlmsvc_file_file(struct nlm_file *file) +static inline struct file *nlmsvc_file_file(const struct nlm_file *file) { return file->f_file[O_RDONLY] ? file->f_file[O_RDONLY] : file->f_file[O_WRONLY]; @@ -318,6 +319,12 @@ static inline struct inode *nlmsvc_file_inode(struct nlm_file *file) return file_inode(nlmsvc_file_file(file)); } +static inline bool +nlmsvc_file_cannot_lock(const struct nlm_file *file) +{ + return exportfs_cannot_lock(nlmsvc_file_file(file)->f_path.dentry->d_sb->s_export_op); +} + static inline int __nlm_privileged_request4(const struct sockaddr *sap) { const struct sockaddr_in *sin = (struct sockaddr_in *)sap; -- cgit v1.2.3