From b623390045a81fc559decb9bfeb79319721d3dfb Mon Sep 17 00:00:00 2001 From: Dai Ngo Date: Sun, 9 Nov 2025 09:05:08 -0800 Subject: [PATCH] NFS: Fix LTP test failures when timestamps are delegated The utimes01 and utime06 tests fail when delegated timestamps are enabled, specifically in subtests that modify the atime and mtime fields using the 'nobody' user ID. The problem can be reproduced as follow: # echo "/media *(rw,no_root_squash,sync)" >> /etc/exports # export -ra # mount -o rw,nfsvers=4.2 127.0.0.1:/media /tmpdir # cd /opt/ltp # ./runltp -d /tmpdir -s utimes01 # ./runltp -d /tmpdir -s utime06 This issue occurs because nfs_setattr does not verify the inode's UID against the caller's fsuid when delegated timestamps are permitted for the inode. This patch adds the UID check and if it does not match then the request is sent to the server for permission checking. Fixes: e12912d94137 ("NFSv4: Add support for delegated atime and mtime attributes") Signed-off-by: Dai Ngo Signed-off-by: Anna Schumaker --- fs/nfs/inode.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c index 18b57c7c2f97b..13ad70fc00d84 100644 --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -718,6 +718,8 @@ nfs_setattr(struct mnt_idmap *idmap, struct dentry *dentry, struct nfs_fattr *fattr; loff_t oldsize = i_size_read(inode); int error = 0; + kuid_t task_uid = current_fsuid(); + kuid_t owner_uid = inode->i_uid; nfs_inc_stats(inode, NFSIOS_VFSSETATTR); @@ -739,9 +741,11 @@ nfs_setattr(struct mnt_idmap *idmap, struct dentry *dentry, if (nfs_have_delegated_mtime(inode) && attr->ia_valid & ATTR_MTIME) { spin_lock(&inode->i_lock); if (attr->ia_valid & ATTR_MTIME_SET) { - nfs_set_timestamps_to_ts(inode, attr); - attr->ia_valid &= ~(ATTR_MTIME|ATTR_MTIME_SET| + if (uid_eq(task_uid, owner_uid)) { + nfs_set_timestamps_to_ts(inode, attr); + attr->ia_valid &= ~(ATTR_MTIME|ATTR_MTIME_SET| ATTR_ATIME|ATTR_ATIME_SET); + } } else { nfs_update_timestamps(inode, attr->ia_valid); attr->ia_valid &= ~(ATTR_MTIME|ATTR_ATIME); @@ -751,10 +755,12 @@ nfs_setattr(struct mnt_idmap *idmap, struct dentry *dentry, attr->ia_valid & ATTR_ATIME && !(attr->ia_valid & ATTR_MTIME)) { if (attr->ia_valid & ATTR_ATIME_SET) { - spin_lock(&inode->i_lock); - nfs_set_timestamps_to_ts(inode, attr); - spin_unlock(&inode->i_lock); - attr->ia_valid &= ~(ATTR_ATIME|ATTR_ATIME_SET); + if (uid_eq(task_uid, owner_uid)) { + spin_lock(&inode->i_lock); + nfs_set_timestamps_to_ts(inode, attr); + spin_unlock(&inode->i_lock); + attr->ia_valid &= ~(ATTR_ATIME|ATTR_ATIME_SET); + } } else { nfs_update_delegated_atime(inode); attr->ia_valid &= ~ATTR_ATIME; -- 2.47.3