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Diffstat (limited to 'fs/fat/file.c')
-rw-r--r--fs/fat/file.c218
1 files changed, 113 insertions, 105 deletions
diff --git a/fs/fat/file.c b/fs/fat/file.c
index c614175876e0..27cc1164ec36 100644
--- a/fs/fat/file.c
+++ b/fs/fat/file.c
@@ -8,6 +8,7 @@
#include <linux/capability.h>
#include <linux/module.h>
+#include <linux/mount.h>
#include <linux/time.h>
#include <linux/msdos_fs.h>
#include <linux/smp_lock.h>
@@ -46,10 +47,9 @@ int fat_generic_ioctl(struct inode *inode, struct file *filp,
mutex_lock(&inode->i_mutex);
- if (IS_RDONLY(inode)) {
- err = -EROFS;
- goto up;
- }
+ err = mnt_want_write(filp->f_path.mnt);
+ if (err)
+ goto up_no_drop_write;
/*
* ATTR_VOLUME and ATTR_DIR cannot be changed; this also
@@ -105,7 +105,9 @@ int fat_generic_ioctl(struct inode *inode, struct file *filp,
MSDOS_I(inode)->i_attrs = attr & ATTR_UNUSED;
mark_inode_dirty(inode);
- up:
+up:
+ mnt_drop_write(filp->f_path.mnt);
+up_no_drop_write:
mutex_unlock(&inode->i_mutex);
return err;
}
@@ -155,104 +157,6 @@ out:
return err;
}
-static int check_mode(const struct msdos_sb_info *sbi, mode_t mode)
-{
- mode_t req = mode & ~S_IFMT;
-
- /*
- * Of the r and x bits, all (subject to umask) must be present. Of the
- * w bits, either all (subject to umask) or none must be present.
- */
-
- if (S_ISREG(mode)) {
- req &= ~sbi->options.fs_fmask;
-
- if ((req & (S_IRUGO | S_IXUGO)) !=
- ((S_IRUGO | S_IXUGO) & ~sbi->options.fs_fmask))
- return -EPERM;
-
- if ((req & S_IWUGO) != 0 &&
- (req & S_IWUGO) != (S_IWUGO & ~sbi->options.fs_fmask))
- return -EPERM;
- } else if (S_ISDIR(mode)) {
- req &= ~sbi->options.fs_dmask;
-
- if ((req & (S_IRUGO | S_IXUGO)) !=
- ((S_IRUGO | S_IXUGO) & ~sbi->options.fs_dmask))
- return -EPERM;
-
- if ((req & S_IWUGO) != 0 &&
- (req & S_IWUGO) != (S_IWUGO & ~sbi->options.fs_dmask))
- return -EPERM;
- } else {
- return -EPERM;
- }
-
- return 0;
-}
-
-int fat_notify_change(struct dentry *dentry, struct iattr *attr)
-{
- struct msdos_sb_info *sbi = MSDOS_SB(dentry->d_sb);
- struct inode *inode = dentry->d_inode;
- int mask, error = 0;
-
- lock_kernel();
-
- /*
- * Expand the file. Since inode_setattr() updates ->i_size
- * before calling the ->truncate(), but FAT needs to fill the
- * hole before it.
- */
- if (attr->ia_valid & ATTR_SIZE) {
- if (attr->ia_size > inode->i_size) {
- error = fat_cont_expand(inode, attr->ia_size);
- if (error || attr->ia_valid == ATTR_SIZE)
- goto out;
- attr->ia_valid &= ~ATTR_SIZE;
- }
- }
-
- error = inode_change_ok(inode, attr);
- if (error) {
- if (sbi->options.quiet)
- error = 0;
- goto out;
- }
- if (((attr->ia_valid & ATTR_UID) &&
- (attr->ia_uid != sbi->options.fs_uid)) ||
- ((attr->ia_valid & ATTR_GID) &&
- (attr->ia_gid != sbi->options.fs_gid)))
- error = -EPERM;
-
- if (error) {
- if (sbi->options.quiet)
- error = 0;
- goto out;
- }
-
- if (attr->ia_valid & ATTR_MODE) {
- error = check_mode(sbi, attr->ia_mode);
- if (error != 0 && !sbi->options.quiet)
- goto out;
- }
-
- error = inode_setattr(inode, attr);
- if (error)
- goto out;
-
- if (S_ISDIR(inode->i_mode))
- mask = sbi->options.fs_dmask;
- else
- mask = sbi->options.fs_fmask;
- inode->i_mode &= S_IFMT | (S_IRWXUGO & ~mask);
-out:
- unlock_kernel();
- return error;
-}
-
-EXPORT_SYMBOL_GPL(fat_notify_change);
-
/* Free all clusters after the skip'th cluster. */
static int fat_free(struct inode *inode, int skip)
{
@@ -304,7 +208,7 @@ static int fat_free(struct inode *inode, int skip)
} else if (ret == FAT_ENT_FREE) {
fat_fs_panic(sb,
"%s: invalid cluster chain (i_pos %lld)",
- __FUNCTION__, MSDOS_I(inode)->i_pos);
+ __func__, MSDOS_I(inode)->i_pos);
ret = -EIO;
} else if (ret > 0) {
err = fat_ent_write(inode, &fatent, FAT_ENT_EOF, wait);
@@ -353,8 +257,112 @@ int fat_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
}
EXPORT_SYMBOL_GPL(fat_getattr);
+static int fat_check_mode(const struct msdos_sb_info *sbi, struct inode *inode,
+ mode_t mode)
+{
+ mode_t mask, req = mode & ~S_IFMT;
+
+ if (S_ISREG(mode))
+ mask = sbi->options.fs_fmask;
+ else
+ mask = sbi->options.fs_dmask;
+
+ /*
+ * Of the r and x bits, all (subject to umask) must be present. Of the
+ * w bits, either all (subject to umask) or none must be present.
+ */
+ req &= ~mask;
+ if ((req & (S_IRUGO | S_IXUGO)) != (inode->i_mode & (S_IRUGO|S_IXUGO)))
+ return -EPERM;
+ if ((req & S_IWUGO) && ((req & S_IWUGO) != (S_IWUGO & ~mask)))
+ return -EPERM;
+
+ return 0;
+}
+
+static int fat_allow_set_time(struct msdos_sb_info *sbi, struct inode *inode)
+{
+ mode_t allow_utime = sbi->options.allow_utime;
+
+ if (current->fsuid != inode->i_uid) {
+ if (in_group_p(inode->i_gid))
+ allow_utime >>= 3;
+ if (allow_utime & MAY_WRITE)
+ return 1;
+ }
+
+ /* use a default check */
+ return 0;
+}
+
+int fat_setattr(struct dentry *dentry, struct iattr *attr)
+{
+ struct msdos_sb_info *sbi = MSDOS_SB(dentry->d_sb);
+ struct inode *inode = dentry->d_inode;
+ int mask, error = 0;
+ unsigned int ia_valid;
+
+ lock_kernel();
+
+ /*
+ * Expand the file. Since inode_setattr() updates ->i_size
+ * before calling the ->truncate(), but FAT needs to fill the
+ * hole before it.
+ */
+ if (attr->ia_valid & ATTR_SIZE) {
+ if (attr->ia_size > inode->i_size) {
+ error = fat_cont_expand(inode, attr->ia_size);
+ if (error || attr->ia_valid == ATTR_SIZE)
+ goto out;
+ attr->ia_valid &= ~ATTR_SIZE;
+ }
+ }
+
+ /* Check for setting the inode time. */
+ ia_valid = attr->ia_valid;
+ if (ia_valid & (ATTR_MTIME_SET | ATTR_ATIME_SET)) {
+ if (fat_allow_set_time(sbi, inode))
+ attr->ia_valid &= ~(ATTR_MTIME_SET | ATTR_ATIME_SET);
+ }
+
+ error = inode_change_ok(inode, attr);
+ attr->ia_valid = ia_valid;
+ if (error) {
+ if (sbi->options.quiet)
+ error = 0;
+ goto out;
+ }
+ if (((attr->ia_valid & ATTR_UID) &&
+ (attr->ia_uid != sbi->options.fs_uid)) ||
+ ((attr->ia_valid & ATTR_GID) &&
+ (attr->ia_gid != sbi->options.fs_gid)) ||
+ ((attr->ia_valid & ATTR_MODE) &&
+ fat_check_mode(sbi, inode, attr->ia_mode) < 0))
+ error = -EPERM;
+
+ if (error) {
+ if (sbi->options.quiet)
+ error = 0;
+ goto out;
+ }
+
+ error = inode_setattr(inode, attr);
+ if (error)
+ goto out;
+
+ if (S_ISDIR(inode->i_mode))
+ mask = sbi->options.fs_dmask;
+ else
+ mask = sbi->options.fs_fmask;
+ inode->i_mode &= S_IFMT | (S_IRWXUGO & ~mask);
+out:
+ unlock_kernel();
+ return error;
+}
+EXPORT_SYMBOL_GPL(fat_setattr);
+
const struct inode_operations fat_file_inode_operations = {
.truncate = fat_truncate,
- .setattr = fat_notify_change,
+ .setattr = fat_setattr,
.getattr = fat_getattr,
};
generated by cgit v1.2.3 (git 2.0.4) at 2024-05-28 14:07:07 +0000