From b2e4cda71ed062c87573b016d2d956a62f4258ed 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 [ Upstream commit b623390045a81fc559decb9bfeb79319721d3dfb ] 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 Signed-off-by: Sasha Levin --- 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 5bf5fb5ddd34..5bab9db5417c 100644 --- a/fs/nfs/inode.c +++ b/fs/nfs/inode.c @@ -711,6 +711,8 @@ nfs_setattr(struct mnt_idmap *idmap, struct dentry *dentry, struct inode *inode = d_inode(dentry); struct nfs_fattr *fattr; int error = 0; + kuid_t task_uid = current_fsuid(); + kuid_t owner_uid = inode->i_uid; nfs_inc_stats(inode, NFSIOS_VFSSETATTR); @@ -732,9 +734,11 @@ 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); @@ -744,10 +748,12 @@ 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;