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 (current->fsuid != inode->i_uid ||
39 (!in_group_p(attr->ia_gid) && attr->ia_gid != inode->i_gid)) &&
43 /* Make sure a caller can chmod. */
44 if (ia_valid & ATTR_MODE) {
45 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
47 /* Also check the setgid bit! */
48 if (!in_group_p((ia_valid & ATTR_GID) ? attr->ia_gid :
49 inode->i_gid) && !capable(CAP_FSETID))
50 attr->ia_mode &= ~S_ISGID;
53 /* Check for setting the inode time. */
54 if (ia_valid & (ATTR_MTIME_SET | ATTR_ATIME_SET)) {
55 if (current->fsuid != inode->i_uid && !capable(CAP_FOWNER))
64 EXPORT_SYMBOL(inode_change_ok);
66 int inode_setattr_flags(struct inode *inode, unsigned int flags)
68 unsigned int oldflags, newflags;
70 oldflags = inode->i_flags;
71 newflags = oldflags & ~(S_IMMUTABLE | S_IUNLINK | S_BARRIER);
72 if (flags & ATTR_FLAG_IMMUTABLE)
73 newflags |= S_IMMUTABLE;
74 if (flags & ATTR_FLAG_IUNLINK)
75 newflags |= S_IUNLINK;
76 if (flags & ATTR_FLAG_BARRIER)
77 newflags |= S_BARRIER;
79 if (oldflags ^ newflags)
80 inode->i_flags = newflags;
84 int inode_setattr(struct inode * inode, struct iattr * attr)
86 unsigned int ia_valid = attr->ia_valid;
89 if (ia_valid & ATTR_SIZE) {
90 if (attr->ia_size != i_size_read(inode)) {
91 error = vmtruncate(inode, attr->ia_size);
92 if (error || (ia_valid == ATTR_SIZE))
96 * We skipped the truncate but must still update
99 ia_valid |= ATTR_MTIME|ATTR_CTIME;
103 if (ia_valid & ATTR_UID)
104 inode->i_uid = attr->ia_uid;
105 if (ia_valid & ATTR_GID)
106 inode->i_gid = attr->ia_gid;
107 if (ia_valid & ATTR_XID)
108 inode->i_xid = attr->ia_xid;
109 if (ia_valid & ATTR_ATIME)
110 inode->i_atime = attr->ia_atime;
111 if (ia_valid & ATTR_MTIME)
112 inode->i_mtime = attr->ia_mtime;
113 if (ia_valid & ATTR_CTIME)
114 inode->i_ctime = attr->ia_ctime;
115 if (ia_valid & ATTR_MODE) {
116 umode_t mode = attr->ia_mode;
118 if (!in_group_p(inode->i_gid) && !capable(CAP_FSETID))
120 inode->i_mode = mode;
122 if (ia_valid & ATTR_ATTR_FLAG)
123 inode_setattr_flags(inode, attr->ia_attr_flags);
124 mark_inode_dirty(inode);
129 EXPORT_SYMBOL(inode_setattr);
131 int setattr_mask(unsigned int ia_valid)
133 unsigned long dn_mask = 0;
135 if (ia_valid & ATTR_UID)
136 dn_mask |= DN_ATTRIB;
137 if (ia_valid & ATTR_GID)
138 dn_mask |= DN_ATTRIB;
139 if (ia_valid & ATTR_XID)
140 dn_mask |= DN_ATTRIB;
141 if (ia_valid & ATTR_SIZE)
142 dn_mask |= DN_MODIFY;
143 /* both times implies a utime(s) call */
144 if ((ia_valid & (ATTR_ATIME|ATTR_MTIME)) == (ATTR_ATIME|ATTR_MTIME))
145 dn_mask |= DN_ATTRIB;
146 else if (ia_valid & ATTR_ATIME)
147 dn_mask |= DN_ACCESS;
148 else if (ia_valid & ATTR_MTIME)
149 dn_mask |= DN_MODIFY;
150 if (ia_valid & ATTR_MODE)
151 dn_mask |= DN_ATTRIB;
155 int notify_change(struct dentry * dentry, struct iattr * attr)
157 struct inode *inode = dentry->d_inode;
158 mode_t mode = inode->i_mode;
160 struct timespec now = CURRENT_TIME;
161 unsigned int ia_valid = attr->ia_valid;
166 attr->ia_ctime = now;
167 if (!(ia_valid & ATTR_ATIME_SET))
168 attr->ia_atime = now;
169 if (!(ia_valid & ATTR_MTIME_SET))
170 attr->ia_mtime = now;
171 if (ia_valid & ATTR_KILL_SUID) {
172 attr->ia_valid &= ~ATTR_KILL_SUID;
173 if (mode & S_ISUID) {
174 if (!(ia_valid & ATTR_MODE)) {
175 ia_valid = attr->ia_valid |= ATTR_MODE;
176 attr->ia_mode = inode->i_mode;
178 attr->ia_mode &= ~S_ISUID;
181 if (ia_valid & ATTR_KILL_SGID) {
182 attr->ia_valid &= ~ ATTR_KILL_SGID;
183 if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) {
184 if (!(ia_valid & ATTR_MODE)) {
185 ia_valid = attr->ia_valid |= ATTR_MODE;
186 attr->ia_mode = inode->i_mode;
188 attr->ia_mode &= ~S_ISGID;
194 if (inode->i_op && inode->i_op->setattr) {
195 error = security_inode_setattr(dentry, attr);
197 error = inode->i_op->setattr(dentry, attr);
199 error = inode_change_ok(inode, attr);
201 error = security_inode_setattr(dentry, attr);
203 if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) ||
204 (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid) ||
205 (ia_valid & ATTR_XID && attr->ia_xid != inode->i_xid))
206 error = DQUOT_TRANSFER(inode, attr) ? -EDQUOT : 0;
208 error = inode_setattr(inode, attr);
212 unsigned long dn_mask = setattr_mask(ia_valid);
214 dnotify_parent(dentry, dn_mask);
219 EXPORT_SYMBOL(notify_change);