[mirror_ubuntu-artful-kernel.git] / fs / attr.c

/*
 *  linux/fs/attr.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 *  changes by Thomas Schoebel-Theuer
 */

#include <linux/export.h>
#include <linux/time.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/capability.h>
#include <linux/fsnotify.h>
#include <linux/fcntl.h>
#include <linux/security.h>
#include <linux/evm.h>
#include <linux/ima.h>

static bool chown_ok(const struct inode *inode, kuid_t uid)
{
	if (uid_eq(current_fsuid(), inode->i_uid) &&
	    uid_eq(uid, inode->i_uid))
		return true;
	if (capable_wrt_inode_uidgid(inode, CAP_CHOWN))
		return true;
	if (ns_capable(inode->i_sb->s_user_ns, CAP_CHOWN))
		return true;
	return false;
}

static bool chgrp_ok(const struct inode *inode, kgid_t gid)
{
	if (uid_eq(current_fsuid(), inode->i_uid) &&
	    (in_group_p(gid) || gid_eq(gid, inode->i_gid)))
		return true;
	if (capable_wrt_inode_uidgid(inode, CAP_CHOWN))
		return true;
	if (ns_capable(inode->i_sb->s_user_ns, CAP_CHOWN))
		return true;
	return false;
}

/**
 * inode_change_ok - check if attribute changes to an inode are allowed
 * @inode:	inode to check
 * @attr:	attributes to change
 *
 * Check if we are allowed to change the attributes contained in @attr
 * in the given inode.  This includes the normal unix access permission
 * checks, as well as checks for rlimits and others.
 *
 * Should be called as the first thing in ->setattr implementations,
 * possibly after taking additional locks.
 */
int inode_change_ok(const struct inode *inode, struct iattr *attr)
{
	unsigned int ia_valid = attr->ia_valid;

	/*
	 * First check size constraints.  These can't be overriden using
	 * ATTR_FORCE.
	 */
	if (ia_valid & ATTR_SIZE) {
		int error = inode_newsize_ok(inode, attr->ia_size);
		if (error)
			return error;
	}

	/* If force is set do it anyway. */
	if (ia_valid & ATTR_FORCE)
		return 0;

	/* Make sure a caller can chown. */
	if ((ia_valid & ATTR_UID) && !chown_ok(inode, attr->ia_uid))
		return -EPERM;

	/* Make sure caller can chgrp. */
	if ((ia_valid & ATTR_GID) && !chgrp_ok(inode, attr->ia_gid))
		return -EPERM;

	/* Make sure a caller can chmod. */
	if (ia_valid & ATTR_MODE) {
		if (!inode_owner_or_capable(inode))
			return -EPERM;
		/* Also check the setgid bit! */
		if (!in_group_p((ia_valid & ATTR_GID) ? attr->ia_gid :
				inode->i_gid) &&
		    !capable_wrt_inode_uidgid(inode, CAP_FSETID))
			attr->ia_mode &= ~S_ISGID;
	}

	/* Check for setting the inode time. */
	if (ia_valid & (ATTR_MTIME_SET | ATTR_ATIME_SET | ATTR_TIMES_SET)) {
		if (!inode_owner_or_capable(inode))
			return -EPERM;
	}

	return 0;
}
EXPORT_SYMBOL(inode_change_ok);

/**
 * inode_newsize_ok - may this inode be truncated to a given size
 * @inode:	the inode to be truncated
 * @offset:	the new size to assign to the inode
 * @Returns:	0 on success, -ve errno on failure
 *
 * inode_newsize_ok must be called with i_mutex held.
 *
 * inode_newsize_ok will check filesystem limits and ulimits to check that the
 * new inode size is within limits. inode_newsize_ok will also send SIGXFSZ
 * when necessary. Caller must not proceed with inode size change if failure is
 * returned. @inode must be a file (not directory), with appropriate
 * permissions to allow truncate (inode_newsize_ok does NOT check these
 * conditions).
 */
int inode_newsize_ok(const struct inode *inode, loff_t offset)
{
	if (inode->i_size < offset) {
		unsigned long limit;

		limit = rlimit(RLIMIT_FSIZE);
		if (limit != RLIM_INFINITY && offset > limit)
			goto out_sig;
		if (offset > inode->i_sb->s_maxbytes)
			goto out_big;
	} else {
		/*
		 * truncation of in-use swapfiles is disallowed - it would
		 * cause subsequent swapout to scribble on the now-freed
		 * blocks.
		 */
		if (IS_SWAPFILE(inode))
			return -ETXTBSY;
	}

	return 0;
out_sig:
	send_sig(SIGXFSZ, current, 0);
out_big:
	return -EFBIG;
}
EXPORT_SYMBOL(inode_newsize_ok);

/**
 * setattr_copy - copy simple metadata updates into the generic inode
 * @inode:	the inode to be updated
 * @attr:	the new attributes
 *
 * setattr_copy must be called with i_mutex held.
 *
 * setattr_copy updates the inode's metadata with that specified
 * in attr. Noticeably missing is inode size update, which is more complex
 * as it requires pagecache updates.
 *
 * The inode is not marked as dirty after this operation. The rationale is
 * that for "simple" filesystems, the struct inode is the inode storage.
 * The caller is free to mark the inode dirty afterwards if needed.
 */
void setattr_copy(struct inode *inode, const struct iattr *attr)
{
	unsigned int ia_valid = attr->ia_valid;

	if (ia_valid & ATTR_UID)
		inode->i_uid = attr->ia_uid;
	if (ia_valid & ATTR_GID)
		inode->i_gid = attr->ia_gid;
	if (ia_valid & ATTR_ATIME)
		inode->i_atime = timespec_trunc(attr->ia_atime,
						inode->i_sb->s_time_gran);
	if (ia_valid & ATTR_MTIME)
		inode->i_mtime = timespec_trunc(attr->ia_mtime,
						inode->i_sb->s_time_gran);
	if (ia_valid & ATTR_CTIME)
		inode->i_ctime = timespec_trunc(attr->ia_ctime,
						inode->i_sb->s_time_gran);
	if (ia_valid & ATTR_MODE) {
		umode_t mode = attr->ia_mode;

		if (!in_group_p(inode->i_gid) &&
		    !capable_wrt_inode_uidgid(inode, CAP_FSETID))
			mode &= ~S_ISGID;
		inode->i_mode = mode;
	}
}
EXPORT_SYMBOL(setattr_copy);

/**
 * notify_change - modify attributes of a filesytem object
 * @dentry:	object affected
 * @iattr:	new attributes
 * @delegated_inode: returns inode, if the inode is delegated
 *
 * The caller must hold the i_mutex on the affected object.
 *
 * If notify_change discovers a delegation in need of breaking,
 * it will return -EWOULDBLOCK and return a reference to the inode in
 * delegated_inode.  The caller should then break the delegation and
 * retry.  Because breaking a delegation may take a long time, the
 * caller should drop the i_mutex before doing so.
 *
 * Alternatively, a caller may pass NULL for delegated_inode.  This may
 * be appropriate for callers that expect the underlying filesystem not
 * to be NFS exported.  Also, passing NULL is fine for callers holding
 * the file open for write, as there can be no conflicting delegation in
 * that case.
 */
int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **delegated_inode)
{
	struct inode *inode = dentry->d_inode;
	umode_t mode = inode->i_mode;
	int error;
	struct timespec now;
	unsigned int ia_valid = attr->ia_valid;

	WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex));

	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(inode)) {
			error = inode_permission(inode, MAY_WRITE);
			if (error)
				return error;
		}
	}

	if ((ia_valid & ATTR_MODE)) {
		umode_t amode = attr->ia_mode;
		/* Flag setting protected by i_mutex */
		if (is_sxid(amode))
			inode->i_flags &= ~S_NOSEC;
	}

	now = current_fs_time(inode->i_sb);

	attr->ia_ctime = now;
	if (!(ia_valid & ATTR_ATIME_SET))
		attr->ia_atime = now;
	if (!(ia_valid & ATTR_MTIME_SET))
		attr->ia_mtime = now;
	if (ia_valid & ATTR_KILL_PRIV) {
		attr->ia_valid &= ~ATTR_KILL_PRIV;
		ia_valid &= ~ATTR_KILL_PRIV;
		error = security_inode_need_killpriv(dentry);
		if (error > 0)
			error = security_inode_killpriv(dentry);
		if (error)
			return error;
	}

	/*
	 * We now pass ATTR_KILL_S*ID to the lower level setattr function so
	 * that the function has the ability to reinterpret a mode change
	 * that's due to these bits. This adds an implicit restriction that
	 * no function will ever call notify_change with both ATTR_MODE and
	 * ATTR_KILL_S*ID set.
	 */
	if ((ia_valid & (ATTR_KILL_SUID|ATTR_KILL_SGID)) &&
	    (ia_valid & ATTR_MODE))
		BUG();

	if (ia_valid & ATTR_KILL_SUID) {
		if (mode & S_ISUID) {
			ia_valid = attr->ia_valid |= ATTR_MODE;
			attr->ia_mode = (inode->i_mode & ~S_ISUID);
		}
	}
	if (ia_valid & ATTR_KILL_SGID) {
		if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) {
			if (!(ia_valid & ATTR_MODE)) {
				ia_valid = attr->ia_valid |= ATTR_MODE;
				attr->ia_mode = inode->i_mode;
			}
			attr->ia_mode &= ~S_ISGID;
		}
	}
	if (!(attr->ia_valid & ~(ATTR_KILL_SUID | ATTR_KILL_SGID)))
		return 0;

	/*
	 * Verify that uid/gid changes are valid in the target
	 * namespace of the superblock.
	 */
	if (ia_valid & ATTR_UID &&
	    !kuid_has_mapping(inode->i_sb->s_user_ns, attr->ia_uid))
		return -EOVERFLOW;
	if (ia_valid & ATTR_GID &&
	    !kgid_has_mapping(inode->i_sb->s_user_ns, attr->ia_gid))
		return -EOVERFLOW;

	/* Don't allow modifications of files with invalid uids or
	 * gids unless those uids & gids are being made valid.
	 */
	if (!(ia_valid & ATTR_UID) && !uid_valid(inode->i_uid))
		return -EOVERFLOW;
	if (!(ia_valid & ATTR_GID) && !gid_valid(inode->i_gid))
		return -EOVERFLOW;

	error = security_inode_setattr(dentry, attr);
	if (error)
		return error;
	error = try_break_deleg(inode, delegated_inode);
	if (error)
		return error;

	if (inode->i_op->setattr)
		error = inode->i_op->setattr(dentry, attr);
	else
		error = simple_setattr(dentry, attr);

	if (!error) {
		fsnotify_change(dentry, ia_valid);
		ima_inode_post_setattr(dentry);
		evm_inode_post_setattr(dentry, ia_valid);
	}

	return error;
}
EXPORT_SYMBOL(notify_change);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/fs/attr.c
	3	*
	4	* Copyright (C) 1991, 1992 Linus Torvalds
	5	* changes by Thomas Schoebel-Theuer
	6	*/
	7
630d9c47	8	#include <linux/export.h>
1da177e4 LT	9	#include <linux/time.h>
	10	#include <linux/mm.h>
	11	#include <linux/string.h>
16f7e0fe	12	#include <linux/capability.h>
0eeca283	13	#include <linux/fsnotify.h>
1da177e4	14	#include <linux/fcntl.h>
1da177e4	15	#include <linux/security.h>
975d2943	16	#include <linux/evm.h>
9957a504	17	#include <linux/ima.h>
1da177e4	18
915c5a4e EB	19	static bool chown_ok(const struct inode *inode, kuid_t uid)
	20	{
	21	if (uid_eq(current_fsuid(), inode->i_uid) &&
	22	uid_eq(uid, inode->i_uid))
	23	return true;
	24	if (capable_wrt_inode_uidgid(inode, CAP_CHOWN))
	25	return true;
	26	if (ns_capable(inode->i_sb->s_user_ns, CAP_CHOWN))
	27	return true;
	28	return false;
	29	}
	30
	31	static bool chgrp_ok(const struct inode *inode, kgid_t gid)
	32	{
	33	if (uid_eq(current_fsuid(), inode->i_uid) &&
	34	(in_group_p(gid) \|\| gid_eq(gid, inode->i_gid)))
	35	return true;
	36	if (capable_wrt_inode_uidgid(inode, CAP_CHOWN))
	37	return true;
	38	if (ns_capable(inode->i_sb->s_user_ns, CAP_CHOWN))
	39	return true;
	40	return false;
	41	}
	42
2c27c65e CH	43	/**
	44	* inode_change_ok - check if attribute changes to an inode are allowed
	45	* @inode: inode to check
	46	* @attr: attributes to change
	47	*
	48	* Check if we are allowed to change the attributes contained in @attr
	49	* in the given inode. This includes the normal unix access permission
	50	* checks, as well as checks for rlimits and others.
	51	*
	52	* Should be called as the first thing in ->setattr implementations,
	53	* possibly after taking additional locks.
	54	*/
25d9e2d1	55	int inode_change_ok(const struct inode inode, struct iattr attr)
1da177e4	56	{
1da177e4 LT	57	unsigned int ia_valid = attr->ia_valid;
1da177e4 LT	58
2c27c65e CH	59	/*
	60	* First check size constraints. These can't be overriden using
	61	* ATTR_FORCE.
	62	*/
	63	if (ia_valid & ATTR_SIZE) {
	64	int error = inode_newsize_ok(inode, attr->ia_size);
	65	if (error)
	66	return error;
	67	}
	68
1da177e4 LT	69	/* If force is set do it anyway. */
1da177e4 LT	70	if (ia_valid & ATTR_FORCE)
2c27c65e	71	return 0;
1da177e4 LT	72
1da177e4 LT	73	/* Make sure a caller can chown. */
915c5a4e	74	if ((ia_valid & ATTR_UID) && !chown_ok(inode, attr->ia_uid))
2c27c65e	75	return -EPERM;
1da177e4 LT	76
1da177e4 LT	77	/* Make sure caller can chgrp. */
915c5a4e	78	if ((ia_valid & ATTR_GID) && !chgrp_ok(inode, attr->ia_gid))
2c27c65e	79	return -EPERM;
1da177e4 LT	80
	81	/* Make sure a caller can chmod. */
	82	if (ia_valid & ATTR_MODE) {
2e149670	83	if (!inode_owner_or_capable(inode))
2c27c65e	84	return -EPERM;
1da177e4 LT	85	/* Also check the setgid bit! */
1da177e4 LT	86	if (!in_group_p((ia_valid & ATTR_GID) ? attr->ia_gid :
7fa294c8	87	inode->i_gid) &&
23adbe12	88	!capable_wrt_inode_uidgid(inode, CAP_FSETID))
1da177e4 LT	89	attr->ia_mode &= ~S_ISGID;
	90	}
	91
	92	/* Check for setting the inode time. */
9767d749	93	if (ia_valid & (ATTR_MTIME_SET \| ATTR_ATIME_SET \| ATTR_TIMES_SET)) {
2e149670	94	if (!inode_owner_or_capable(inode))
2c27c65e	95	return -EPERM;
1da177e4	96	}
2c27c65e CH	97
2c27c65e CH	98	return 0;
1da177e4	99	}
1da177e4 LT	100	EXPORT_SYMBOL(inode_change_ok);
1da177e4 LT	101
25d9e2d1	102	/**
	103	* inode_newsize_ok - may this inode be truncated to a given size
	104	* @inode: the inode to be truncated
	105	* @offset: the new size to assign to the inode
	106	* @Returns: 0 on success, -ve errno on failure
	107	*
7bb46a67	108	* inode_newsize_ok must be called with i_mutex held.
7bb46a67	109	*
25d9e2d1	110	* inode_newsize_ok will check filesystem limits and ulimits to check that the
	111	* new inode size is within limits. inode_newsize_ok will also send SIGXFSZ
	112	* when necessary. Caller must not proceed with inode size change if failure is
	113	* returned. @inode must be a file (not directory), with appropriate
	114	* permissions to allow truncate (inode_newsize_ok does NOT check these
	115	* conditions).
25d9e2d1	116	*/
	117	int inode_newsize_ok(const struct inode *inode, loff_t offset)
	118	{
	119	if (inode->i_size < offset) {
	120	unsigned long limit;
	121
d554ed89	122	limit = rlimit(RLIMIT_FSIZE);
25d9e2d1	123	if (limit != RLIM_INFINITY && offset > limit)
	124	goto out_sig;
	125	if (offset > inode->i_sb->s_maxbytes)
	126	goto out_big;
	127	} else {
	128	/*
	129	* truncation of in-use swapfiles is disallowed - it would
	130	* cause subsequent swapout to scribble on the now-freed
	131	* blocks.
	132	*/
	133	if (IS_SWAPFILE(inode))
	134	return -ETXTBSY;
	135	}
	136
	137	return 0;
	138	out_sig:
	139	send_sig(SIGXFSZ, current, 0);
	140	out_big:
	141	return -EFBIG;
	142	}
	143	EXPORT_SYMBOL(inode_newsize_ok);
	144
7bb46a67	145	/**
6a1a90ad	146	* setattr_copy - copy simple metadata updates into the generic inode
7bb46a67	147	* @inode: the inode to be updated
	148	* @attr: the new attributes
	149	*
6a1a90ad	150	* setattr_copy must be called with i_mutex held.
7bb46a67	151	*
6a1a90ad	152	* setattr_copy updates the inode's metadata with that specified
25985edc	153	* in attr. Noticeably missing is inode size update, which is more complex
2c27c65e	154	* as it requires pagecache updates.
7bb46a67	155	*
	156	* The inode is not marked as dirty after this operation. The rationale is
	157	* that for "simple" filesystems, the struct inode is the inode storage.
	158	* The caller is free to mark the inode dirty afterwards if needed.
	159	*/
6a1a90ad	160	void setattr_copy(struct inode inode, const struct iattr attr)
1da177e4 LT	161	{
1da177e4 LT	162	unsigned int ia_valid = attr->ia_valid;
4a30131e	163
1da177e4 LT	164	if (ia_valid & ATTR_UID)
	165	inode->i_uid = attr->ia_uid;
	166	if (ia_valid & ATTR_GID)
	167	inode->i_gid = attr->ia_gid;
	168	if (ia_valid & ATTR_ATIME)
	169	inode->i_atime = timespec_trunc(attr->ia_atime,
	170	inode->i_sb->s_time_gran);
	171	if (ia_valid & ATTR_MTIME)
	172	inode->i_mtime = timespec_trunc(attr->ia_mtime,
	173	inode->i_sb->s_time_gran);
	174	if (ia_valid & ATTR_CTIME)
	175	inode->i_ctime = timespec_trunc(attr->ia_ctime,
	176	inode->i_sb->s_time_gran);
	177	if (ia_valid & ATTR_MODE) {
	178	umode_t mode = attr->ia_mode;
	179
7fa294c8	180	if (!in_group_p(inode->i_gid) &&
23adbe12	181	!capable_wrt_inode_uidgid(inode, CAP_FSETID))
1da177e4 LT	182	mode &= ~S_ISGID;
	183	inode->i_mode = mode;
	184	}
7bb46a67	185	}
6a1a90ad	186	EXPORT_SYMBOL(setattr_copy);
7bb46a67	187
27ac0ffe BF	188	/**
	189	* notify_change - modify attributes of a filesytem object
	190	* @dentry: object affected
	191	* @iattr: new attributes
	192	* @delegated_inode: returns inode, if the inode is delegated
	193	*
	194	* The caller must hold the i_mutex on the affected object.
	195	*
	196	* If notify_change discovers a delegation in need of breaking,
	197	* it will return -EWOULDBLOCK and return a reference to the inode in
	198	* delegated_inode. The caller should then break the delegation and
	199	* retry. Because breaking a delegation may take a long time, the
	200	* caller should drop the i_mutex before doing so.
	201	*
	202	* Alternatively, a caller may pass NULL for delegated_inode. This may
	203	* be appropriate for callers that expect the underlying filesystem not
	204	* to be NFS exported. Also, passing NULL is fine for callers holding
	205	* the file open for write, as there can be no conflicting delegation in
	206	* that case.
	207	*/
	208	int notify_change(struct dentry * dentry, struct iattr * attr, struct inode **delegated_inode)
1da177e4 LT	209	{
1da177e4 LT	210	struct inode *inode = dentry->d_inode;
8d334acd	211	umode_t mode = inode->i_mode;
1da177e4 LT	212	int error;
	213	struct timespec now;
	214	unsigned int ia_valid = attr->ia_valid;
	215
c4107b30 AM	216	WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex));
c4107b30 AM	217
beb29e05 MS	218	if (ia_valid & (ATTR_MODE \| ATTR_UID \| ATTR_GID \| ATTR_TIMES_SET)) {
	219	if (IS_IMMUTABLE(inode) \|\| IS_APPEND(inode))
	220	return -EPERM;
	221	}
	222
f1e96ec9 MS	223	/*
	224	* If utimes(2) and friends are called with times == NULL (or both
	225	* times are UTIME_NOW), then we need to check for write permission
	226	*/
	227	if (ia_valid & ATTR_TOUCH) {
	228	if (IS_IMMUTABLE(inode))
	229	return -EPERM;
	230
	231	if (!inode_owner_or_capable(inode)) {
	232	error = inode_permission(inode, MAY_WRITE);
	233	if (error)
	234	return error;
	235	}
	236	}
	237
69b45732	238	if ((ia_valid & ATTR_MODE)) {
8d334acd	239	umode_t amode = attr->ia_mode;
69b45732 AK	240	/* Flag setting protected by i_mutex */
	241	if (is_sxid(amode))
	242	inode->i_flags &= ~S_NOSEC;
	243	}
	244
1da177e4 LT	245	now = current_fs_time(inode->i_sb);
	246
	247	attr->ia_ctime = now;
	248	if (!(ia_valid & ATTR_ATIME_SET))
	249	attr->ia_atime = now;
	250	if (!(ia_valid & ATTR_MTIME_SET))
	251	attr->ia_mtime = now;
b5376771 SH	252	if (ia_valid & ATTR_KILL_PRIV) {
	253	attr->ia_valid &= ~ATTR_KILL_PRIV;
	254	ia_valid &= ~ATTR_KILL_PRIV;
	255	error = security_inode_need_killpriv(dentry);
	256	if (error > 0)
	257	error = security_inode_killpriv(dentry);
	258	if (error)
	259	return error;
	260	}
6de0ec00 JL	261
	262	/*
	263	* We now pass ATTR_KILL_S*ID to the lower level setattr function so
	264	* that the function has the ability to reinterpret a mode change
	265	* that's due to these bits. This adds an implicit restriction that
	266	* no function will ever call notify_change with both ATTR_MODE and
	267	* ATTR_KILL_S*ID set.
	268	*/
	269	if ((ia_valid & (ATTR_KILL_SUID\|ATTR_KILL_SGID)) &&
	270	(ia_valid & ATTR_MODE))
	271	BUG();
	272
1da177e4	273	if (ia_valid & ATTR_KILL_SUID) {
1da177e4	274	if (mode & S_ISUID) {
6de0ec00 JL	275	ia_valid = attr->ia_valid \|= ATTR_MODE;
6de0ec00 JL	276	attr->ia_mode = (inode->i_mode & ~S_ISUID);
1da177e4 LT	277	}
	278	}
	279	if (ia_valid & ATTR_KILL_SGID) {
1da177e4 LT	280	if ((mode & (S_ISGID \| S_IXGRP)) == (S_ISGID \| S_IXGRP)) {
	281	if (!(ia_valid & ATTR_MODE)) {
	282	ia_valid = attr->ia_valid \|= ATTR_MODE;
	283	attr->ia_mode = inode->i_mode;
	284	}
	285	attr->ia_mode &= ~S_ISGID;
	286	}
	287	}
6de0ec00	288	if (!(attr->ia_valid & ~(ATTR_KILL_SUID \| ATTR_KILL_SGID)))
1da177e4 LT	289	return 0;
1da177e4 LT	290
7ccd1a40 SF	291	/*
	292	* Verify that uid/gid changes are valid in the target
	293	* namespace of the superblock.
	294	*/
	295	if (ia_valid & ATTR_UID &&
	296	!kuid_has_mapping(inode->i_sb->s_user_ns, attr->ia_uid))
	297	return -EOVERFLOW;
	298	if (ia_valid & ATTR_GID &&
	299	!kgid_has_mapping(inode->i_sb->s_user_ns, attr->ia_gid))
	300	return -EOVERFLOW;
	301
be494dcc EB	302	/* Don't allow modifications of files with invalid uids or
	303	* gids unless those uids & gids are being made valid.
	304	*/
	305	if (!(ia_valid & ATTR_UID) && !uid_valid(inode->i_uid))
	306	return -EOVERFLOW;
	307	if (!(ia_valid & ATTR_GID) && !gid_valid(inode->i_gid))
	308	return -EOVERFLOW;
	309
a77b72da	310	error = security_inode_setattr(dentry, attr);
27ac0ffe BF	311	if (error)
	312	return error;
	313	error = try_break_deleg(inode, delegated_inode);
a77b72da MS	314	if (error)
	315	return error;
	316
eef2380c	317	if (inode->i_op->setattr)
a77b72da	318	error = inode->i_op->setattr(dentry, attr);
eef2380c CH	319	else
eef2380c CH	320	error = simple_setattr(dentry, attr);
1da177e4	321
975d2943	322	if (!error) {
0eeca283	323	fsnotify_change(dentry, ia_valid);
9957a504	324	ima_inode_post_setattr(dentry);
975d2943 MZ	325	evm_inode_post_setattr(dentry, ia_valid);
975d2943 MZ	326	}
0eeca283	327
1da177e4 LT	328	return error;
1da177e4 LT	329	}
1da177e4	330	EXPORT_SYMBOL(notify_change);