X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=fs%2Fxattr.c;h=01bb8135e14aafcc4b8782b749374e6b79049afc;hb=3be2264be3c00865116f997dc53ebcc90fe7fc4b;hp=1858552a6a1a0c6af76afb92316507c7d2d352eb;hpb=42492594043d621a7910ff5877c3eb9202870b45;p=safe%2Fjmp%2Flinux-2.6 diff --git a/fs/xattr.c b/fs/xattr.c index 1858552..01bb813 100644 --- a/fs/xattr.c +++ b/fs/xattr.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include #include @@ -32,8 +33,6 @@ xattr_permission(struct inode *inode, const char *name, int mask) * filesystem or on an immutable / append-only inode. */ if (mask & MAY_WRITE) { - if (IS_RDONLY(inode)) - return -EROFS; if (IS_IMMUTABLE(inode) || IS_APPEND(inode)) return -EPERM; } @@ -64,25 +63,31 @@ xattr_permission(struct inode *inode, const char *name, int mask) return -EPERM; } - return permission(inode, mask, NULL); + return inode_permission(inode, mask); } -int -vfs_setxattr(struct dentry *dentry, char *name, void *value, - size_t size, int flags) +/** + * __vfs_setxattr_noperm - perform setxattr operation without performing + * permission checks. + * + * @dentry - object to perform setxattr on + * @name - xattr name to set + * @value - value to set @name to + * @size - size of @value + * @flags - flags to pass into filesystem operations + * + * returns the result of the internal setxattr or setsecurity operations. + * + * This function requires the caller to lock the inode's i_mutex before it + * is executed. It also assumes that the caller will make the appropriate + * permission checks. + */ +int __vfs_setxattr_noperm(struct dentry *dentry, const char *name, + const void *value, size_t size, int flags) { struct inode *inode = dentry->d_inode; - int error; - - error = xattr_permission(inode, name, MAY_WRITE); - if (error) - return error; + int error = -EOPNOTSUPP; - mutex_lock(&inode->i_mutex); - error = security_inode_setxattr(dentry, name, value, size, flags); - if (error) - goto out; - error = -EOPNOTSUPP; if (inode->i_op->setxattr) { error = inode->i_op->setxattr(dentry, name, value, size, flags); if (!error) { @@ -98,6 +103,29 @@ vfs_setxattr(struct dentry *dentry, char *name, void *value, if (!error) fsnotify_xattr(dentry); } + + return error; +} + + +int +vfs_setxattr(struct dentry *dentry, const char *name, const void *value, + size_t size, int flags) +{ + struct inode *inode = dentry->d_inode; + int error; + + error = xattr_permission(inode, name, MAY_WRITE); + if (error) + return error; + + mutex_lock(&inode->i_mutex); + error = security_inode_setxattr(dentry, name, value, size, flags); + if (error) + goto out; + + error = __vfs_setxattr_noperm(dentry, name, value, size, flags); + out: mutex_unlock(&inode->i_mutex); return error; @@ -132,7 +160,7 @@ out_noalloc: EXPORT_SYMBOL_GPL(xattr_getsecurity); ssize_t -vfs_getxattr(struct dentry *dentry, char *name, void *value, size_t size) +vfs_getxattr(struct dentry *dentry, const char *name, void *value, size_t size) { struct inode *inode = dentry->d_inode; int error; @@ -145,11 +173,6 @@ vfs_getxattr(struct dentry *dentry, char *name, void *value, size_t size) if (error) return error; - if (inode->i_op->getxattr) - error = inode->i_op->getxattr(dentry, name, value, size); - else - error = -EOPNOTSUPP; - if (!strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN)) { const char *suffix = name + XATTR_SECURITY_PREFIX_LEN; @@ -158,9 +181,15 @@ vfs_getxattr(struct dentry *dentry, char *name, void *value, size_t size) * Only overwrite the return value if a security module * is actually active. */ - if (ret != -EOPNOTSUPP) - error = ret; + if (ret == -EOPNOTSUPP) + goto nolsm; + return ret; } +nolsm: + if (inode->i_op->getxattr) + error = inode->i_op->getxattr(dentry, name, value, size); + else + error = -EOPNOTSUPP; return error; } @@ -175,7 +204,7 @@ vfs_listxattr(struct dentry *d, char *list, size_t size) if (error) return error; error = -EOPNOTSUPP; - if (d->d_inode->i_op && d->d_inode->i_op->listxattr) { + if (d->d_inode->i_op->listxattr) { error = d->d_inode->i_op->listxattr(d, list, size); } else { error = security_inode_listsecurity(d->d_inode, list, size); @@ -187,7 +216,7 @@ vfs_listxattr(struct dentry *d, char *list, size_t size) EXPORT_SYMBOL_GPL(vfs_listxattr); int -vfs_removexattr(struct dentry *dentry, char *name) +vfs_removexattr(struct dentry *dentry, const char *name) { struct inode *inode = dentry->d_inode; int error; @@ -218,7 +247,7 @@ EXPORT_SYMBOL_GPL(vfs_removexattr); * Extended attribute SET operations */ static long -setxattr(struct dentry *d, char __user *name, void __user *value, +setxattr(struct dentry *d, const char __user *name, const void __user *value, size_t size, int flags) { int error; @@ -237,13 +266,9 @@ setxattr(struct dentry *d, char __user *name, void __user *value, if (size) { if (size > XATTR_SIZE_MAX) return -E2BIG; - kvalue = kmalloc(size, GFP_KERNEL); - if (!kvalue) - return -ENOMEM; - if (copy_from_user(kvalue, value, size)) { - kfree(kvalue); - return -EFAULT; - } + kvalue = memdup_user(value, size); + if (IS_ERR(kvalue)) + return PTR_ERR(kvalue); } error = vfs_setxattr(d, kname, kvalue, size, flags); @@ -251,39 +276,46 @@ setxattr(struct dentry *d, char __user *name, void __user *value, return error; } -asmlinkage long -sys_setxattr(char __user *path, char __user *name, void __user *value, - size_t size, int flags) +SYSCALL_DEFINE5(setxattr, const char __user *, pathname, + const char __user *, name, const void __user *, value, + size_t, size, int, flags) { - struct nameidata nd; + struct path path; int error; - error = user_path_walk(path, &nd); + error = user_path(pathname, &path); if (error) return error; - error = setxattr(nd.dentry, name, value, size, flags); - path_release(&nd); + error = mnt_want_write(path.mnt); + if (!error) { + error = setxattr(path.dentry, name, value, size, flags); + mnt_drop_write(path.mnt); + } + path_put(&path); return error; } -asmlinkage long -sys_lsetxattr(char __user *path, char __user *name, void __user *value, - size_t size, int flags) +SYSCALL_DEFINE5(lsetxattr, const char __user *, pathname, + const char __user *, name, const void __user *, value, + size_t, size, int, flags) { - struct nameidata nd; + struct path path; int error; - error = user_path_walk_link(path, &nd); + error = user_lpath(pathname, &path); if (error) return error; - error = setxattr(nd.dentry, name, value, size, flags); - path_release(&nd); + error = mnt_want_write(path.mnt); + if (!error) { + error = setxattr(path.dentry, name, value, size, flags); + mnt_drop_write(path.mnt); + } + path_put(&path); return error; } -asmlinkage long -sys_fsetxattr(int fd, char __user *name, void __user *value, - size_t size, int flags) +SYSCALL_DEFINE5(fsetxattr, int, fd, const char __user *, name, + const void __user *,value, size_t, size, int, flags) { struct file *f; struct dentry *dentry; @@ -294,7 +326,11 @@ sys_fsetxattr(int fd, char __user *name, void __user *value, return error; dentry = f->f_path.dentry; audit_inode(NULL, dentry); - error = setxattr(dentry, name, value, size, flags); + error = mnt_want_write_file(f); + if (!error) { + error = setxattr(dentry, name, value, size, flags); + mnt_drop_write(f->f_path.mnt); + } fput(f); return error; } @@ -303,7 +339,8 @@ sys_fsetxattr(int fd, char __user *name, void __user *value, * Extended attribute GET operations */ static ssize_t -getxattr(struct dentry *d, char __user *name, void __user *value, size_t size) +getxattr(struct dentry *d, const char __user *name, void __user *value, + size_t size) { ssize_t error; void *kvalue = NULL; @@ -336,38 +373,36 @@ getxattr(struct dentry *d, char __user *name, void __user *value, size_t size) return error; } -asmlinkage ssize_t -sys_getxattr(char __user *path, char __user *name, void __user *value, - size_t size) +SYSCALL_DEFINE4(getxattr, const char __user *, pathname, + const char __user *, name, void __user *, value, size_t, size) { - struct nameidata nd; + struct path path; ssize_t error; - error = user_path_walk(path, &nd); + error = user_path(pathname, &path); if (error) return error; - error = getxattr(nd.dentry, name, value, size); - path_release(&nd); + error = getxattr(path.dentry, name, value, size); + path_put(&path); return error; } -asmlinkage ssize_t -sys_lgetxattr(char __user *path, char __user *name, void __user *value, - size_t size) +SYSCALL_DEFINE4(lgetxattr, const char __user *, pathname, + const char __user *, name, void __user *, value, size_t, size) { - struct nameidata nd; + struct path path; ssize_t error; - error = user_path_walk_link(path, &nd); + error = user_lpath(pathname, &path); if (error) return error; - error = getxattr(nd.dentry, name, value, size); - path_release(&nd); + error = getxattr(path.dentry, name, value, size); + path_put(&path); return error; } -asmlinkage ssize_t -sys_fgetxattr(int fd, char __user *name, void __user *value, size_t size) +SYSCALL_DEFINE4(fgetxattr, int, fd, const char __user *, name, + void __user *, value, size_t, size) { struct file *f; ssize_t error = -EBADF; @@ -411,36 +446,35 @@ listxattr(struct dentry *d, char __user *list, size_t size) return error; } -asmlinkage ssize_t -sys_listxattr(char __user *path, char __user *list, size_t size) +SYSCALL_DEFINE3(listxattr, const char __user *, pathname, char __user *, list, + size_t, size) { - struct nameidata nd; + struct path path; ssize_t error; - error = user_path_walk(path, &nd); + error = user_path(pathname, &path); if (error) return error; - error = listxattr(nd.dentry, list, size); - path_release(&nd); + error = listxattr(path.dentry, list, size); + path_put(&path); return error; } -asmlinkage ssize_t -sys_llistxattr(char __user *path, char __user *list, size_t size) +SYSCALL_DEFINE3(llistxattr, const char __user *, pathname, char __user *, list, + size_t, size) { - struct nameidata nd; + struct path path; ssize_t error; - error = user_path_walk_link(path, &nd); + error = user_lpath(pathname, &path); if (error) return error; - error = listxattr(nd.dentry, list, size); - path_release(&nd); + error = listxattr(path.dentry, list, size); + path_put(&path); return error; } -asmlinkage ssize_t -sys_flistxattr(int fd, char __user *list, size_t size) +SYSCALL_DEFINE3(flistxattr, int, fd, char __user *, list, size_t, size) { struct file *f; ssize_t error = -EBADF; @@ -458,7 +492,7 @@ sys_flistxattr(int fd, char __user *list, size_t size) * Extended attribute REMOVE operations */ static long -removexattr(struct dentry *d, char __user *name) +removexattr(struct dentry *d, const char __user *name) { int error; char kname[XATTR_NAME_MAX + 1]; @@ -472,36 +506,43 @@ removexattr(struct dentry *d, char __user *name) return vfs_removexattr(d, kname); } -asmlinkage long -sys_removexattr(char __user *path, char __user *name) +SYSCALL_DEFINE2(removexattr, const char __user *, pathname, + const char __user *, name) { - struct nameidata nd; + struct path path; int error; - error = user_path_walk(path, &nd); + error = user_path(pathname, &path); if (error) return error; - error = removexattr(nd.dentry, name); - path_release(&nd); + error = mnt_want_write(path.mnt); + if (!error) { + error = removexattr(path.dentry, name); + mnt_drop_write(path.mnt); + } + path_put(&path); return error; } -asmlinkage long -sys_lremovexattr(char __user *path, char __user *name) +SYSCALL_DEFINE2(lremovexattr, const char __user *, pathname, + const char __user *, name) { - struct nameidata nd; + struct path path; int error; - error = user_path_walk_link(path, &nd); + error = user_lpath(pathname, &path); if (error) return error; - error = removexattr(nd.dentry, name); - path_release(&nd); + error = mnt_want_write(path.mnt); + if (!error) { + error = removexattr(path.dentry, name); + mnt_drop_write(path.mnt); + } + path_put(&path); return error; } -asmlinkage long -sys_fremovexattr(int fd, char __user *name) +SYSCALL_DEFINE2(fremovexattr, int, fd, const char __user *, name) { struct file *f; struct dentry *dentry; @@ -512,7 +553,11 @@ sys_fremovexattr(int fd, char __user *name) return error; dentry = f->f_path.dentry; audit_inode(NULL, dentry); - error = removexattr(dentry, name); + error = mnt_want_write_file(f); + if (!error) { + error = removexattr(dentry, name); + mnt_drop_write(f->f_path.mnt); + } fput(f); return error; } @@ -545,10 +590,10 @@ strcmp_prefix(const char *a, const char *a_prefix) /* * Find the xattr_handler with the matching prefix. */ -static struct xattr_handler * -xattr_resolve_name(struct xattr_handler **handlers, const char **name) +static const struct xattr_handler * +xattr_resolve_name(const struct xattr_handler **handlers, const char **name) { - struct xattr_handler *handler; + const struct xattr_handler *handler; if (!*name) return NULL; @@ -569,13 +614,12 @@ xattr_resolve_name(struct xattr_handler **handlers, const char **name) ssize_t generic_getxattr(struct dentry *dentry, const char *name, void *buffer, size_t size) { - struct xattr_handler *handler; - struct inode *inode = dentry->d_inode; + const struct xattr_handler *handler; - handler = xattr_resolve_name(inode->i_sb->s_xattr, &name); + handler = xattr_resolve_name(dentry->d_sb->s_xattr, &name); if (!handler) return -EOPNOTSUPP; - return handler->get(inode, name, buffer, size); + return handler->get(dentry, name, buffer, size, handler->flags); } /* @@ -585,18 +629,20 @@ generic_getxattr(struct dentry *dentry, const char *name, void *buffer, size_t s ssize_t generic_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size) { - struct inode *inode = dentry->d_inode; - struct xattr_handler *handler, **handlers = inode->i_sb->s_xattr; + const struct xattr_handler *handler, **handlers = dentry->d_sb->s_xattr; unsigned int size = 0; if (!buffer) { - for_each_xattr_handler(handlers, handler) - size += handler->list(inode, NULL, 0, NULL, 0); + for_each_xattr_handler(handlers, handler) { + size += handler->list(dentry, NULL, 0, NULL, 0, + handler->flags); + } } else { char *buf = buffer; for_each_xattr_handler(handlers, handler) { - size = handler->list(inode, buf, buffer_size, NULL, 0); + size = handler->list(dentry, buf, buffer_size, + NULL, 0, handler->flags); if (size > buffer_size) return -ERANGE; buf += size; @@ -613,15 +659,14 @@ generic_listxattr(struct dentry *dentry, char *buffer, size_t buffer_size) int generic_setxattr(struct dentry *dentry, const char *name, const void *value, size_t size, int flags) { - struct xattr_handler *handler; - struct inode *inode = dentry->d_inode; + const struct xattr_handler *handler; if (size == 0) value = ""; /* empty EA, do not remove */ - handler = xattr_resolve_name(inode->i_sb->s_xattr, &name); + handler = xattr_resolve_name(dentry->d_sb->s_xattr, &name); if (!handler) return -EOPNOTSUPP; - return handler->set(inode, name, value, size, flags); + return handler->set(dentry, name, value, size, 0, handler->flags); } /* @@ -631,13 +676,13 @@ generic_setxattr(struct dentry *dentry, const char *name, const void *value, siz int generic_removexattr(struct dentry *dentry, const char *name) { - struct xattr_handler *handler; - struct inode *inode = dentry->d_inode; + const struct xattr_handler *handler; - handler = xattr_resolve_name(inode->i_sb->s_xattr, &name); + handler = xattr_resolve_name(dentry->d_sb->s_xattr, &name); if (!handler) return -EOPNOTSUPP; - return handler->set(inode, name, NULL, 0, XATTR_REPLACE); + return handler->set(dentry, name, NULL, 0, + XATTR_REPLACE, handler->flags); } EXPORT_SYMBOL(generic_getxattr);