4 * Copyright (C) 1991, 1992 Linus Torvalds
5 * changes by Thomas Schoebel-Theuer
8 #include <linux/module.h>
9 #include <linux/time.h>
11 #include <linux/string.h>
12 #include <linux/smp_lock.h>
13 #include <linux/dnotify.h>
14 #include <linux/fcntl.h>
15 #include <linux/quotaops.h>
16 #include <linux/security.h>
18 /* Taken over from the old code... */
20 /* POSIX UID/GID verification for setting inode attributes. */
21 int inode_change_ok(struct inode *inode, struct iattr *attr)
24 unsigned int ia_valid = attr->ia_valid;
26 /* If force is set do it anyway. */
27 if (ia_valid & ATTR_FORCE)
30 /* Make sure a caller can chown. */
31 if ((ia_valid & ATTR_UID) &&
32 (current->fsuid != inode->i_uid ||
33 attr->ia_uid != inode->i_uid) && !capable(CAP_CHOWN))
36 /* Make sure caller can chgrp. */
37 if ((ia_valid & ATTR_GID) &&
38 (!in_group_p(attr->ia_gid) && attr->ia_gid != inode->i_gid) &&
42 /* Make sure a caller can chmod. */
43 if (ia_valid & ATTR_MODE) {
44 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
46 /* Also check the setgid bit! */
47 if (!in_group_p((ia_valid & ATTR_GID) ? attr->ia_gid :
48 inode->i_gid) && !capable(CAP_FSETID))
49 attr->ia_mode &= ~S_ISGID;
52 /* Check for setting the inode time. */
53 if (ia_valid & (ATTR_MTIME_SET | ATTR_ATIME_SET)) {
54 if (current->fsuid != inode->i_uid && !capable(CAP_FOWNER))
63 EXPORT_SYMBOL(inode_change_ok);
65 int inode_setattr_flags(struct inode *inode, unsigned int flags)
67 unsigned int oldflags, newflags;
69 oldflags = inode->i_flags;
70 newflags = oldflags & ~(S_IMMUTABLE | S_IUNLINK | S_BARRIER);
71 if (flags & ATTR_FLAG_IMMUTABLE)
72 newflags |= S_IMMUTABLE;
73 if (flags & ATTR_FLAG_IUNLINK)
74 newflags |= S_IUNLINK;
75 if (flags & ATTR_FLAG_BARRIER)
76 newflags |= S_BARRIER;
78 if (oldflags ^ newflags)
79 inode->i_flags = newflags;
83 int inode_setattr(struct inode * inode, struct iattr * attr)
85 unsigned int ia_valid = attr->ia_valid;
88 if (ia_valid & ATTR_SIZE) {
89 if (attr->ia_size != i_size_read(inode)) {
90 error = vmtruncate(inode, attr->ia_size);
91 if (error || (ia_valid == ATTR_SIZE))
95 * We skipped the truncate but must still update
98 ia_valid |= ATTR_MTIME|ATTR_CTIME;
102 if (ia_valid & ATTR_UID)
103 inode->i_uid = attr->ia_uid;
104 if (ia_valid & ATTR_GID)
105 inode->i_gid = attr->ia_gid;
106 if (ia_valid & ATTR_XID)
107 inode->i_xid = attr->ia_xid;
108 if (ia_valid & ATTR_ATIME)
109 inode->i_atime = attr->ia_atime;
110 if (ia_valid & ATTR_MTIME)
111 inode->i_mtime = attr->ia_mtime;
112 if (ia_valid & ATTR_CTIME)
113 inode->i_ctime = attr->ia_ctime;
114 if (ia_valid & ATTR_MODE) {
115 umode_t mode = attr->ia_mode;
117 if (!in_group_p(inode->i_gid) && !capable(CAP_FSETID))
119 inode->i_mode = mode;
121 if (ia_valid & ATTR_ATTR_FLAG)
122 inode_setattr_flags(inode, attr->ia_attr_flags);
123 mark_inode_dirty(inode);
128 EXPORT_SYMBOL(inode_setattr);
130 int setattr_mask(unsigned int ia_valid)
132 unsigned long dn_mask = 0;
134 if (ia_valid & ATTR_UID)
135 dn_mask |= DN_ATTRIB;
136 if (ia_valid & ATTR_GID)
137 dn_mask |= DN_ATTRIB;
138 if (ia_valid & ATTR_XID)
139 dn_mask |= DN_ATTRIB;
140 if (ia_valid & ATTR_SIZE)
141 dn_mask |= DN_MODIFY;
142 /* both times implies a utime(s) call */
143 if ((ia_valid & (ATTR_ATIME|ATTR_MTIME)) == (ATTR_ATIME|ATTR_MTIME))
144 dn_mask |= DN_ATTRIB;
145 else if (ia_valid & ATTR_ATIME)
146 dn_mask |= DN_ACCESS;
147 else if (ia_valid & ATTR_MTIME)
148 dn_mask |= DN_MODIFY;
149 if (ia_valid & ATTR_MODE)
150 dn_mask |= DN_ATTRIB;
154 int notify_change(struct dentry * dentry, struct iattr * attr)
156 struct inode *inode = dentry->d_inode;
157 mode_t mode = inode->i_mode;
159 struct timespec now = CURRENT_TIME;
160 unsigned int ia_valid = attr->ia_valid;
165 attr->ia_ctime = now;
166 if (!(ia_valid & ATTR_ATIME_SET))
167 attr->ia_atime = now;
168 if (!(ia_valid & ATTR_MTIME_SET))
169 attr->ia_mtime = now;
170 if (ia_valid & ATTR_KILL_SUID) {
171 attr->ia_valid &= ~ATTR_KILL_SUID;
172 if (mode & S_ISUID) {
173 if (!(ia_valid & ATTR_MODE)) {
174 ia_valid = attr->ia_valid |= ATTR_MODE;
175 attr->ia_mode = inode->i_mode;
177 attr->ia_mode &= ~S_ISUID;
180 if (ia_valid & ATTR_KILL_SGID) {
181 attr->ia_valid &= ~ ATTR_KILL_SGID;
182 if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) {
183 if (!(ia_valid & ATTR_MODE)) {
184 ia_valid = attr->ia_valid |= ATTR_MODE;
185 attr->ia_mode = inode->i_mode;
187 attr->ia_mode &= ~S_ISGID;
193 if (inode->i_op && inode->i_op->setattr) {
194 error = security_inode_setattr(dentry, attr);
196 error = inode->i_op->setattr(dentry, attr);
198 error = inode_change_ok(inode, attr);
200 error = security_inode_setattr(dentry, attr);
202 if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) ||
203 (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid) ||
204 (ia_valid & ATTR_XID && attr->ia_xid != inode->i_xid))
205 error = DQUOT_TRANSFER(inode, attr) ? -EDQUOT : 0;
207 error = inode_setattr(inode, attr);
211 unsigned long dn_mask = setattr_mask(ia_valid);
213 dnotify_parent(dentry, dn_mask);
218 EXPORT_SYMBOL(notify_change);