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author | Linus Torvalds <torvalds@linux-foundation.org> | 2021-09-09 12:45:26 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-09-09 12:45:26 -0700 |
commit | 7b871c7713d1eafc3a614883bbdf68ab1dffa883 (patch) | |
tree | 942e920ec617dbd23fafe1a368f2ec69203d152e /fs | |
parent | e2e694b9e6f3ec7deeb233b6b0fe20b6a47b304b (diff) | |
parent | d75b9fa053e4cd278281386d860c26fdbfbe9d03 (diff) | |
download | lwn-7b871c7713d1eafc3a614883bbdf68ab1dffa883.tar.gz lwn-7b871c7713d1eafc3a614883bbdf68ab1dffa883.zip |
Merge branch 'work.gfs2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull gfs2 setattr updates from Al Viro:
"Make it possible for filesystems to use a generic 'may_setattr()' and
switch gfs2 to using it"
* 'work.gfs2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
gfs2: Switch to may_setattr in gfs2_setattr
fs: Move notify_change permission checks into may_setattr
Diffstat (limited to 'fs')
-rw-r--r-- | fs/attr.c | 50 | ||||
-rw-r--r-- | fs/gfs2/inode.c | 4 |
2 files changed, 33 insertions, 21 deletions
diff --git a/fs/attr.c b/fs/attr.c index 87ef39db1c34..473d21b3a86d 100644 --- a/fs/attr.c +++ b/fs/attr.c @@ -249,6 +249,34 @@ void setattr_copy(struct user_namespace *mnt_userns, struct inode *inode, } EXPORT_SYMBOL(setattr_copy); +int may_setattr(struct user_namespace *mnt_userns, struct inode *inode, + unsigned int ia_valid) +{ + int error; + + if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | ATTR_TIMES_SET)) { + if (IS_IMMUTABLE(inode) || IS_APPEND(inode)) + return -EPERM; + } + + /* + * If utimes(2) and friends are called with times == NULL (or both + * times are UTIME_NOW), then we need to check for write permission + */ + if (ia_valid & ATTR_TOUCH) { + if (IS_IMMUTABLE(inode)) + return -EPERM; + + if (!inode_owner_or_capable(mnt_userns, inode)) { + error = inode_permission(mnt_userns, inode, MAY_WRITE); + if (error) + return error; + } + } + return 0; +} +EXPORT_SYMBOL(may_setattr); + /** * notify_change - modify attributes of a filesytem object * @mnt_userns: user namespace of the mount the inode was found from @@ -290,25 +318,9 @@ int notify_change(struct user_namespace *mnt_userns, struct dentry *dentry, WARN_ON_ONCE(!inode_is_locked(inode)); - if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID | ATTR_TIMES_SET)) { - if (IS_IMMUTABLE(inode) || IS_APPEND(inode)) - return -EPERM; - } - - /* - * If utimes(2) and friends are called with times == NULL (or both - * times are UTIME_NOW), then we need to check for write permission - */ - if (ia_valid & ATTR_TOUCH) { - if (IS_IMMUTABLE(inode)) - return -EPERM; - - if (!inode_owner_or_capable(mnt_userns, inode)) { - error = inode_permission(mnt_userns, inode, MAY_WRITE); - if (error) - return error; - } - } + error = may_setattr(mnt_userns, inode, ia_valid); + if (error) + return error; if ((ia_valid & ATTR_MODE)) { umode_t amode = attr->ia_mode; diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c index 6e15434b23ac..3130f85d2b3f 100644 --- a/fs/gfs2/inode.c +++ b/fs/gfs2/inode.c @@ -1985,8 +1985,8 @@ static int gfs2_setattr(struct user_namespace *mnt_userns, if (error) goto out; - error = -EPERM; - if (IS_IMMUTABLE(inode) || IS_APPEND(inode)) + error = may_setattr(&init_user_ns, inode, attr->ia_valid); + if (error) goto error; error = setattr_prepare(&init_user_ns, dentry, attr); |