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>
17 #include <linux/time.h>
18 #include <linux/proc_fs.h>
19 #include <linux/devpts_fs.h>
20 #include <linux/vserver/debug.h>
22 /* Taken over from the old code... */
24 /* POSIX UID/GID verification for setting inode attributes. */
25 int inode_change_ok(struct inode *inode, struct iattr *attr)
28 unsigned int ia_valid = attr->ia_valid;
30 /* If force is set do it anyway. */
31 if (ia_valid & ATTR_FORCE)
34 /* Make sure a caller can chown. */
35 if ((ia_valid & ATTR_UID) &&
36 (current->fsuid != inode->i_uid ||
37 attr->ia_uid != inode->i_uid) && !capable(CAP_CHOWN))
40 /* Make sure caller can chgrp. */
41 if ((ia_valid & ATTR_GID) &&
42 (current->fsuid != inode->i_uid ||
43 (!in_group_p(attr->ia_gid) && attr->ia_gid != inode->i_gid)) &&
47 /* Make sure a caller can chmod. */
48 if (ia_valid & ATTR_MODE) {
49 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
51 /* Also check the setgid bit! */
52 if (!in_group_p((ia_valid & ATTR_GID) ? attr->ia_gid :
53 inode->i_gid) && !capable(CAP_FSETID))
54 attr->ia_mode &= ~S_ISGID;
57 /* Check for setting the inode time. */
58 if (ia_valid & (ATTR_MTIME_SET | ATTR_ATIME_SET)) {
59 if (current->fsuid != inode->i_uid && !capable(CAP_FOWNER))
63 /* Check for evil vserver activity */
64 if (vx_check(0, VX_ADMIN))
67 if (IS_BARRIER(inode)) {
68 vxwprintk(1, "xid=%d messing with the barrier.",
72 switch (inode->i_sb->s_magic) {
73 case PROC_SUPER_MAGIC:
74 vxwprintk(1, "xid=%d messing with the procfs.",
77 case DEVPTS_SUPER_MAGIC:
78 if (vx_check(inode->i_xid, VX_IDENT))
80 vxwprintk(1, "xid=%d messing with the devpts.",
90 EXPORT_SYMBOL(inode_change_ok);
92 int inode_setattr_flags(struct inode *inode, unsigned int flags)
94 unsigned int oldflags, newflags;
96 oldflags = inode->i_flags;
97 newflags = oldflags & ~(S_IMMUTABLE | S_IUNLINK | S_BARRIER);
98 if (flags & ATTR_FLAG_IMMUTABLE)
99 newflags |= S_IMMUTABLE;
100 if (flags & ATTR_FLAG_IUNLINK)
101 newflags |= S_IUNLINK;
102 if (flags & ATTR_FLAG_BARRIER)
103 newflags |= S_BARRIER;
105 if (oldflags ^ newflags)
106 inode->i_flags = newflags;
110 int inode_setattr(struct inode * inode, struct iattr * attr)
112 unsigned int ia_valid = attr->ia_valid;
115 if (ia_valid & ATTR_SIZE) {
116 if (attr->ia_size != i_size_read(inode)) {
117 error = vmtruncate(inode, attr->ia_size);
118 if (error || (ia_valid == ATTR_SIZE))
122 * We skipped the truncate but must still update
125 ia_valid |= ATTR_MTIME|ATTR_CTIME;
129 if (ia_valid & ATTR_UID)
130 inode->i_uid = attr->ia_uid;
131 if (ia_valid & ATTR_GID)
132 inode->i_gid = attr->ia_gid;
133 if (ia_valid & ATTR_XID)
134 inode->i_xid = attr->ia_xid;
135 if (ia_valid & ATTR_ATIME)
136 inode->i_atime = timespec_trunc(attr->ia_atime,
137 inode->i_sb->s_time_gran);
138 if (ia_valid & ATTR_MTIME)
139 inode->i_mtime = timespec_trunc(attr->ia_mtime,
140 inode->i_sb->s_time_gran);
141 if (ia_valid & ATTR_CTIME)
142 inode->i_ctime = timespec_trunc(attr->ia_ctime,
143 inode->i_sb->s_time_gran);
144 if (ia_valid & ATTR_MODE) {
145 umode_t mode = attr->ia_mode;
147 if (!in_group_p(inode->i_gid) && !capable(CAP_FSETID))
149 inode->i_mode = mode;
151 if (ia_valid & ATTR_ATTR_FLAG)
152 inode_setattr_flags(inode, attr->ia_attr_flags);
153 mark_inode_dirty(inode);
158 EXPORT_SYMBOL(inode_setattr);
160 int setattr_mask(unsigned int ia_valid)
162 unsigned long dn_mask = 0;
164 if (ia_valid & ATTR_UID)
165 dn_mask |= DN_ATTRIB;
166 if (ia_valid & ATTR_GID)
167 dn_mask |= DN_ATTRIB;
168 if (ia_valid & ATTR_XID)
169 dn_mask |= DN_ATTRIB;
170 if (ia_valid & ATTR_SIZE)
171 dn_mask |= DN_MODIFY;
172 /* both times implies a utime(s) call */
173 if ((ia_valid & (ATTR_ATIME|ATTR_MTIME)) == (ATTR_ATIME|ATTR_MTIME))
174 dn_mask |= DN_ATTRIB;
175 else if (ia_valid & ATTR_ATIME)
176 dn_mask |= DN_ACCESS;
177 else if (ia_valid & ATTR_MTIME)
178 dn_mask |= DN_MODIFY;
179 if (ia_valid & ATTR_MODE)
180 dn_mask |= DN_ATTRIB;
184 int notify_change(struct dentry * dentry, struct iattr * attr)
186 struct inode *inode = dentry->d_inode;
187 mode_t mode = inode->i_mode;
189 struct timespec now = current_fs_time(inode->i_sb);
190 unsigned int ia_valid = attr->ia_valid;
195 attr->ia_ctime = now;
196 if (!(ia_valid & ATTR_ATIME_SET))
197 attr->ia_atime = now;
198 if (!(ia_valid & ATTR_MTIME_SET))
199 attr->ia_mtime = now;
200 if (ia_valid & ATTR_KILL_SUID) {
201 attr->ia_valid &= ~ATTR_KILL_SUID;
202 if (mode & S_ISUID) {
203 if (!(ia_valid & ATTR_MODE)) {
204 ia_valid = attr->ia_valid |= ATTR_MODE;
205 attr->ia_mode = inode->i_mode;
207 attr->ia_mode &= ~S_ISUID;
210 if (ia_valid & ATTR_KILL_SGID) {
211 attr->ia_valid &= ~ ATTR_KILL_SGID;
212 if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) {
213 if (!(ia_valid & ATTR_MODE)) {
214 ia_valid = attr->ia_valid |= ATTR_MODE;
215 attr->ia_mode = inode->i_mode;
217 attr->ia_mode &= ~S_ISGID;
223 if (ia_valid & ATTR_SIZE)
224 down_write(&dentry->d_inode->i_alloc_sem);
226 if (inode->i_op && inode->i_op->setattr) {
227 error = security_inode_setattr(dentry, attr);
229 error = inode->i_op->setattr(dentry, attr);
231 error = inode_change_ok(inode, attr);
233 error = security_inode_setattr(dentry, attr);
235 if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) ||
236 (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid) ||
237 (ia_valid & ATTR_XID && attr->ia_xid != inode->i_xid))
238 error = DQUOT_TRANSFER(inode, attr) ? -EDQUOT : 0;
240 error = inode_setattr(inode, attr);
244 if (ia_valid & ATTR_SIZE)
245 up_write(&dentry->d_inode->i_alloc_sem);
248 unsigned long dn_mask = setattr_mask(ia_valid);
250 dnotify_parent(dentry, dn_mask);
255 EXPORT_SYMBOL(notify_change);