diff options
| -rw-r--r-- | fs/fat/file.c | 44 |
1 files changed, 27 insertions, 17 deletions
diff --git a/fs/fat/file.c b/fs/fat/file.c index 27cc1164ec3..771326b8047 100644 --- a/fs/fat/file.c +++ b/fs/fat/file.c @@ -257,26 +257,34 @@ 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) +static int fat_sanitize_mode(const struct msdos_sb_info *sbi, + struct inode *inode, umode_t *mode_ptr) { - mode_t mask, req = mode & ~S_IFMT; + mode_t mask, perm; - if (S_ISREG(mode)) + /* + * Note, the basic check is already done by a caller of + * (attr->ia_mode & ~MSDOS_VALID_MODE) + */ + + if (S_ISREG(inode->i_mode)) mask = sbi->options.fs_fmask; else mask = sbi->options.fs_dmask; + perm = *mode_ptr & ~(S_IFMT | mask); + /* * 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))) + if ((perm & (S_IRUGO | S_IXUGO)) != (inode->i_mode & (S_IRUGO|S_IXUGO))) return -EPERM; - if ((req & S_IWUGO) && ((req & S_IWUGO) != (S_IWUGO & ~mask))) + if ((perm & S_IWUGO) && ((perm & S_IWUGO) != (S_IWUGO & ~mask))) return -EPERM; + *mode_ptr &= S_IFMT | perm; + return 0; } @@ -299,7 +307,7 @@ 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; + int error = 0; unsigned int ia_valid; lock_kernel(); @@ -332,12 +340,13 @@ int fat_setattr(struct dentry *dentry, struct iattr *attr) 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)) + (attr->ia_mode & ~MSDOS_VALID_MODE))) error = -EPERM; if (error) { @@ -346,15 +355,16 @@ int fat_setattr(struct dentry *dentry, struct iattr *attr) goto out; } - error = inode_setattr(inode, attr); - if (error) - goto out; + /* + * We don't return -EPERM here. Yes, strange, but this is too + * old behavior. + */ + if (attr->ia_valid & ATTR_MODE) { + if (fat_sanitize_mode(sbi, inode, &attr->ia_mode) < 0) + attr->ia_valid &= ~ATTR_MODE; + } - 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); + error = inode_setattr(inode, attr); out: unlock_kernel(); return error; |