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author | Christian Brauner <christian.brauner@ubuntu.com> | 2021-01-21 14:19:26 +0100 |
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committer | Christian Brauner <christian.brauner@ubuntu.com> | 2021-01-24 14:27:16 +0100 |
commit | 2f221d6f7b881d95de1f356a3097d755ab1e47d4 (patch) | |
tree | 3d136e3ade1492f1ab59e09546ffa6f2d723f76d /fs/open.c | |
parent | 21cb47be6fb9ece7e6ee63f6780986faa384a77c (diff) | |
download | linux-stable-2f221d6f7b881d95de1f356a3097d755ab1e47d4.tar.gz linux-stable-2f221d6f7b881d95de1f356a3097d755ab1e47d4.tar.bz2 linux-stable-2f221d6f7b881d95de1f356a3097d755ab1e47d4.zip |
attr: handle idmapped mounts
When file attributes are changed most filesystems rely on the
setattr_prepare(), setattr_copy(), and notify_change() helpers for
initialization and permission checking. Let them handle idmapped mounts.
If the inode is accessed through an idmapped mount map it into the
mount's user namespace. Afterwards the checks are identical to
non-idmapped mounts. If the initial user namespace is passed nothing
changes so non-idmapped mounts will see identical behavior as before.
Helpers that perform checks on the ia_uid and ia_gid fields in struct
iattr assume that ia_uid and ia_gid are intended values and have already
been mapped correctly at the userspace-kernelspace boundary as we
already do today. If the initial user namespace is passed nothing
changes so non-idmapped mounts will see identical behavior as before.
Link: https://lore.kernel.org/r/20210121131959.646623-8-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Diffstat (limited to 'fs/open.c')
-rw-r--r-- | fs/open.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/fs/open.c b/fs/open.c index a6dac6d97988..c3e4dc43dd8d 100644 --- a/fs/open.c +++ b/fs/open.c @@ -61,7 +61,7 @@ int do_truncate(struct dentry *dentry, loff_t length, unsigned int time_attrs, inode_lock(dentry->d_inode); /* Note any delegations or leases have already been broken: */ - ret = notify_change(dentry, &newattrs, NULL); + ret = notify_change(&init_user_ns, dentry, &newattrs, NULL); inode_unlock(dentry->d_inode); return ret; } @@ -580,7 +580,8 @@ retry_deleg: goto out_unlock; newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO); newattrs.ia_valid = ATTR_MODE | ATTR_CTIME; - error = notify_change(path->dentry, &newattrs, &delegated_inode); + error = notify_change(&init_user_ns, path->dentry, &newattrs, + &delegated_inode); out_unlock: inode_unlock(inode); if (delegated_inode) { @@ -671,7 +672,8 @@ retry_deleg: inode_lock(inode); error = security_path_chown(path, uid, gid); if (!error) - error = notify_change(path->dentry, &newattrs, &delegated_inode); + error = notify_change(&init_user_ns, path->dentry, &newattrs, + &delegated_inode); inode_unlock(inode); if (delegated_inode) { error = break_deleg_wait(&delegated_inode); |