X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=fs%2Fnamei.c;h=88baaf2b91677889f6a365bf54d7ba042ea5e4c4;hb=2a737871108de9ba8930f7650d549f1383767f8b;hp=1f6656c3d1b9663fe0a572c423536726dc8ab0ca;hpb=acfa4380efe77e290d3a96b11cd4c9f24f4fbb18;p=safe%2Fjmp%2Flinux-2.6 diff --git a/fs/namei.c b/fs/namei.c index 1f6656c..88baaf2 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -24,6 +24,7 @@ #include #include #include +#include #include #include #include @@ -31,6 +32,7 @@ #include #include #include +#include #include #define ACC_MODE(x) ("\000\004\002\006"[(x)&O_ACCMODE]) @@ -550,6 +552,17 @@ static __always_inline int link_path_walk(const char *name, struct nameidata *nd return result; } +static __always_inline void set_root(struct nameidata *nd) +{ + if (!nd->root.mnt) { + struct fs_struct *fs = current->fs; + read_lock(&fs->lock); + nd->root = fs->root; + path_get(&nd->root); + read_unlock(&fs->lock); + } +} + static __always_inline int __vfs_follow_link(struct nameidata *nd, const char *link) { int res = 0; @@ -558,14 +571,10 @@ static __always_inline int __vfs_follow_link(struct nameidata *nd, const char *l goto fail; if (*link == '/') { - struct fs_struct *fs = current->fs; - + set_root(nd); path_put(&nd->path); - - read_lock(&fs->lock); - nd->path = fs->root; - path_get(&fs->root); - read_unlock(&fs->lock); + nd->path = nd->root; + path_get(&nd->root); } res = link_path_walk(link, nd); @@ -739,19 +748,16 @@ int follow_down(struct vfsmount **mnt, struct dentry **dentry) static __always_inline void follow_dotdot(struct nameidata *nd) { - struct fs_struct *fs = current->fs; + set_root(nd); while(1) { struct vfsmount *parent; struct dentry *old = nd->path.dentry; - read_lock(&fs->lock); - if (nd->path.dentry == fs->root.dentry && - nd->path.mnt == fs->root.mnt) { - read_unlock(&fs->lock); + if (nd->path.dentry == nd->root.dentry && + nd->path.mnt == nd->root.mnt) { break; } - read_unlock(&fs->lock); spin_lock(&dcache_lock); if (nd->path.dentry != nd->path.mnt->mnt_root) { nd->path.dentry = dget(nd->path.dentry->d_parent); @@ -850,6 +856,9 @@ static int __link_path_walk(const char *name, struct nameidata *nd) if (err == -EAGAIN) err = inode_permission(nd->path.dentry->d_inode, MAY_EXEC); + if (!err) + err = ima_path_check(&nd->path, MAY_EXEC, + IMA_COUNT_UPDATE); if (err) break; @@ -1012,25 +1021,23 @@ static int path_walk(const char *name, struct nameidata *nd) return link_path_walk(name, nd); } -/* Returns 0 and nd will be valid on success; Retuns error, otherwise. */ -static int do_path_lookup(int dfd, const char *name, - unsigned int flags, struct nameidata *nd) +static int path_init(int dfd, const char *name, unsigned int flags, struct nameidata *nd) { int retval = 0; int fput_needed; struct file *file; - struct fs_struct *fs = current->fs; nd->last_type = LAST_ROOT; /* if there are only slashes... */ nd->flags = flags; nd->depth = 0; + nd->root.mnt = NULL; if (*name=='/') { - read_lock(&fs->lock); - nd->path = fs->root; - path_get(&fs->root); - read_unlock(&fs->lock); + set_root(nd); + nd->path = nd->root; + path_get(&nd->root); } else if (dfd == AT_FDCWD) { + struct fs_struct *fs = current->fs; read_lock(&fs->lock); nd->path = fs->pwd; path_get(&fs->pwd); @@ -1058,17 +1065,29 @@ static int do_path_lookup(int dfd, const char *name, fput_light(file, fput_needed); } + return 0; - retval = path_walk(name, nd); +fput_fail: + fput_light(file, fput_needed); +out_fail: + return retval; +} + +/* Returns 0 and nd will be valid on success; Retuns error, otherwise. */ +static int do_path_lookup(int dfd, const char *name, + unsigned int flags, struct nameidata *nd) +{ + int retval = path_init(dfd, name, flags, nd); + if (!retval) + retval = path_walk(name, nd); if (unlikely(!retval && !audit_dummy_context() && nd->path.dentry && nd->path.dentry->d_inode)) audit_inode(name, nd->path.dentry); -out_fail: + if (nd->root.mnt) { + path_put(&nd->root); + nd->root.mnt = NULL; + } return retval; - -fput_fail: - fput_light(file, fput_needed); - goto out_fail; } int path_lookup(const char *name, unsigned int flags, @@ -1104,6 +1123,7 @@ int vfs_path_lookup(struct dentry *dentry, struct vfsmount *mnt, nd->last_type = LAST_ROOT; nd->flags = flags; nd->depth = 0; + nd->root.mnt = NULL; nd->path.dentry = dentry; nd->path.mnt = mnt; @@ -1114,8 +1134,12 @@ int vfs_path_lookup(struct dentry *dentry, struct vfsmount *mnt, nd->path.dentry->d_inode)) audit_inode(name, nd->path.dentry); - return retval; + if (nd->root.mnt) { + path_put(&nd->root); + nd->root.mnt = NULL; + } + return retval; } /** @@ -1126,8 +1150,8 @@ int vfs_path_lookup(struct dentry *dentry, struct vfsmount *mnt, * @nd: pointer to nameidata * @open_flags: open intent flags */ -int path_lookup_open(int dfd, const char *name, unsigned int lookup_flags, - struct nameidata *nd, int open_flags) +static int path_lookup_open(int dfd, const char *name, + unsigned int lookup_flags, struct nameidata *nd, int open_flags) { struct file *filp = get_empty_filp(); int err; @@ -1244,6 +1268,8 @@ struct dentry *lookup_one_len(const char *name, struct dentry *base, int len) int err; struct qstr this; + WARN_ON_ONCE(!mutex_is_locked(&base->d_inode->i_mutex)); + err = __lookup_one_len(name, &this, base, len); if (err) return ERR_PTR(err); @@ -1470,7 +1496,7 @@ int vfs_create(struct inode *dir, struct dentry *dentry, int mode, error = security_inode_create(dir, dentry, mode); if (error) return error; - DQUOT_INIT(dir); + vfs_dq_init(dir); error = dir->i_op->create(dir, dentry, mode, nd); if (!error) fsnotify_create(dir, dentry); @@ -1486,29 +1512,33 @@ int may_open(struct path *path, int acc_mode, int flag) if (!inode) return -ENOENT; - if (S_ISLNK(inode->i_mode)) + switch (inode->i_mode & S_IFMT) { + case S_IFLNK: return -ELOOP; - - if (S_ISDIR(inode->i_mode) && (acc_mode & MAY_WRITE)) - return -EISDIR; - - /* - * FIFO's, sockets and device files are special: they don't - * actually live on the filesystem itself, and as such you - * can write to them even if the filesystem is read-only. - */ - if (S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) { - flag &= ~O_TRUNC; - } else if (S_ISBLK(inode->i_mode) || S_ISCHR(inode->i_mode)) { + case S_IFDIR: + if (acc_mode & MAY_WRITE) + return -EISDIR; + break; + case S_IFBLK: + case S_IFCHR: if (path->mnt->mnt_flags & MNT_NODEV) return -EACCES; - + /*FALLTHRU*/ + case S_IFIFO: + case S_IFSOCK: flag &= ~O_TRUNC; + break; } error = inode_permission(inode, acc_mode); if (error) return error; + + error = ima_path_check(path, + acc_mode & (MAY_READ | MAY_WRITE | MAY_EXEC), + IMA_COUNT_UPDATE); + if (error) + return error; /* * An append-only file must be opened in append mode for writing. */ @@ -1544,7 +1574,7 @@ int may_open(struct path *path, int acc_mode, int flag) error = security_path_truncate(path, 0, ATTR_MTIME|ATTR_CTIME|ATTR_OPEN); if (!error) { - DQUOT_INIT(inode); + vfs_dq_init(inode); error = do_truncate(dentry, 0, ATTR_MTIME|ATTR_CTIME|ATTR_OPEN, @@ -1555,7 +1585,7 @@ int may_open(struct path *path, int acc_mode, int flag) return error; } else if (flag & FMODE_WRITE) - DQUOT_INIT(inode); + vfs_dq_init(inode); return 0; } @@ -1572,7 +1602,7 @@ static int __open_namei_create(struct nameidata *nd, struct path *path, struct dentry *dir = nd->path.dentry; if (!IS_POSIXACL(dir->d_inode)) - mode &= ~current->fs->umask; + mode &= ~current_umask(); error = security_path_mknod(&nd->path, path->dentry, mode, 0); if (error) goto out_unlock; @@ -1628,18 +1658,19 @@ static int open_will_write_to_fs(int flag, struct inode *inode) * open_to_namei_flags() for more details. */ struct file *do_filp_open(int dfd, const char *pathname, - int open_flag, int mode) + int open_flag, int mode, int acc_mode) { struct file *filp; struct nameidata nd; - int acc_mode, error; + int error; struct path path; struct dentry *dir; int count = 0; int will_write; int flag = open_to_namei_flags(open_flag); - acc_mode = MAY_OPEN | ACC_MODE(flag); + if (!acc_mode) + acc_mode = MAY_OPEN | ACC_MODE(flag); /* O_TRUNC implies we need access checks for write permissions */ if (flag & O_TRUNC) @@ -1664,9 +1695,14 @@ struct file *do_filp_open(int dfd, const char *pathname, /* * Create - we need to know the parent. */ - error = do_path_lookup(dfd, pathname, LOOKUP_PARENT, &nd); + error = path_init(dfd, pathname, LOOKUP_PARENT, &nd); + if (error) + return ERR_PTR(error); + error = path_walk(pathname, &nd); if (error) return ERR_PTR(error); + if (unlikely(!audit_dummy_context())) + audit_inode(pathname, nd.path.dentry); /* * We have the parent and last component. First of all, check @@ -1794,6 +1830,8 @@ exit: if (!IS_ERR(nd.intent.open.file)) release_open_intent(&nd); exit_parent: + if (nd.root.mnt) + path_put(&nd.root); path_put(&nd.path); return ERR_PTR(error); @@ -1860,7 +1898,7 @@ do_link: */ struct file *filp_open(const char *filename, int flags, int mode) { - return do_filp_open(AT_FDCWD, filename, flags, mode); + return do_filp_open(AT_FDCWD, filename, flags, mode, 0); } EXPORT_SYMBOL(filp_open); @@ -1938,7 +1976,7 @@ int vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) if (error) return error; - DQUOT_INIT(dir); + vfs_dq_init(dir); error = dir->i_op->mknod(dir, dentry, mode, dev); if (!error) fsnotify_create(dir, dentry); @@ -1962,8 +2000,8 @@ static int may_mknod(mode_t mode) } } -asmlinkage long sys_mknodat(int dfd, const char __user *filename, int mode, - unsigned dev) +SYSCALL_DEFINE4(mknodat, int, dfd, const char __user *, filename, int, mode, + unsigned, dev) { int error; char *tmp; @@ -1983,7 +2021,7 @@ asmlinkage long sys_mknodat(int dfd, const char __user *filename, int mode, goto out_unlock; } if (!IS_POSIXACL(nd.path.dentry->d_inode)) - mode &= ~current->fs->umask; + mode &= ~current_umask(); error = may_mknod(mode); if (error) goto out_dput; @@ -2017,7 +2055,7 @@ out_unlock: return error; } -asmlinkage long sys_mknod(const char __user *filename, int mode, unsigned dev) +SYSCALL_DEFINE3(mknod, const char __user *, filename, int, mode, unsigned, dev) { return sys_mknodat(AT_FDCWD, filename, mode, dev); } @@ -2037,14 +2075,14 @@ int vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) if (error) return error; - DQUOT_INIT(dir); + vfs_dq_init(dir); error = dir->i_op->mkdir(dir, dentry, mode); if (!error) fsnotify_mkdir(dir, dentry); return error; } -asmlinkage long sys_mkdirat(int dfd, const char __user *pathname, int mode) +SYSCALL_DEFINE3(mkdirat, int, dfd, const char __user *, pathname, int, mode) { int error = 0; char * tmp; @@ -2061,7 +2099,7 @@ asmlinkage long sys_mkdirat(int dfd, const char __user *pathname, int mode) goto out_unlock; if (!IS_POSIXACL(nd.path.dentry->d_inode)) - mode &= ~current->fs->umask; + mode &= ~current_umask(); error = mnt_want_write(nd.path.mnt); if (error) goto out_dput; @@ -2081,7 +2119,7 @@ out_err: return error; } -asmlinkage long sys_mkdir(const char __user *pathname, int mode) +SYSCALL_DEFINE2(mkdir, const char __user *, pathname, int, mode) { return sys_mkdirat(AT_FDCWD, pathname, mode); } @@ -2123,7 +2161,7 @@ int vfs_rmdir(struct inode *dir, struct dentry *dentry) if (!dir->i_op->rmdir) return -EPERM; - DQUOT_INIT(dir); + vfs_dq_init(dir); mutex_lock(&dentry->d_inode->i_mutex); dentry_unhash(dentry); @@ -2195,7 +2233,7 @@ exit1: return error; } -asmlinkage long sys_rmdir(const char __user *pathname) +SYSCALL_DEFINE1(rmdir, const char __user *, pathname) { return do_rmdir(AT_FDCWD, pathname); } @@ -2210,7 +2248,7 @@ int vfs_unlink(struct inode *dir, struct dentry *dentry) if (!dir->i_op->unlink) return -EPERM; - DQUOT_INIT(dir); + vfs_dq_init(dir); mutex_lock(&dentry->d_inode->i_mutex); if (d_mountpoint(dentry)) @@ -2291,7 +2329,7 @@ slashes: goto exit2; } -asmlinkage long sys_unlinkat(int dfd, const char __user *pathname, int flag) +SYSCALL_DEFINE3(unlinkat, int, dfd, const char __user *, pathname, int, flag) { if ((flag & ~AT_REMOVEDIR) != 0) return -EINVAL; @@ -2302,7 +2340,7 @@ asmlinkage long sys_unlinkat(int dfd, const char __user *pathname, int flag) return do_unlinkat(dfd, pathname); } -asmlinkage long sys_unlink(const char __user *pathname) +SYSCALL_DEFINE1(unlink, const char __user *, pathname) { return do_unlinkat(AT_FDCWD, pathname); } @@ -2321,15 +2359,15 @@ int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname) if (error) return error; - DQUOT_INIT(dir); + vfs_dq_init(dir); error = dir->i_op->symlink(dir, dentry, oldname); if (!error) fsnotify_create(dir, dentry); return error; } -asmlinkage long sys_symlinkat(const char __user *oldname, - int newdfd, const char __user *newname) +SYSCALL_DEFINE3(symlinkat, const char __user *, oldname, + int, newdfd, const char __user *, newname) { int error; char *from; @@ -2370,7 +2408,7 @@ out_putname: return error; } -asmlinkage long sys_symlink(const char __user *oldname, const char __user *newname) +SYSCALL_DEFINE2(symlink, const char __user *, oldname, const char __user *, newname) { return sys_symlinkat(oldname, AT_FDCWD, newname); } @@ -2405,7 +2443,7 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de return error; mutex_lock(&inode->i_mutex); - DQUOT_INIT(dir); + vfs_dq_init(dir); error = dir->i_op->link(old_dentry, dir, new_dentry); mutex_unlock(&inode->i_mutex); if (!error) @@ -2422,9 +2460,8 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de * with linux 2.0, and to avoid hard-linking to directories * and other special files. --ADM */ -asmlinkage long sys_linkat(int olddfd, const char __user *oldname, - int newdfd, const char __user *newname, - int flags) +SYSCALL_DEFINE5(linkat, int, olddfd, const char __user *, oldname, + int, newdfd, const char __user *, newname, int, flags) { struct dentry *new_dentry; struct nameidata nd; @@ -2473,7 +2510,7 @@ out: return error; } -asmlinkage long sys_link(const char __user *oldname, const char __user *newname) +SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname) { return sys_linkat(AT_FDCWD, oldname, AT_FDCWD, newname, 0); } @@ -2605,8 +2642,8 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry, if (!old_dir->i_op->rename) return -EPERM; - DQUOT_INIT(old_dir); - DQUOT_INIT(new_dir); + vfs_dq_init(old_dir); + vfs_dq_init(new_dir); old_name = fsnotify_oldname_init(old_dentry->d_name.name); @@ -2624,8 +2661,8 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry, return error; } -asmlinkage long sys_renameat(int olddfd, const char __user *oldname, - int newdfd, const char __user *newname) +SYSCALL_DEFINE4(renameat, int, olddfd, const char __user *, oldname, + int, newdfd, const char __user *, newname) { struct dentry *old_dir, *new_dir; struct dentry *old_dentry, *new_dentry; @@ -2718,7 +2755,7 @@ exit: return error; } -asmlinkage long sys_rename(const char __user *oldname, const char __user *newname) +SYSCALL_DEFINE2(rename, const char __user *, oldname, const char __user *, newname) { return sys_renameat(AT_FDCWD, oldname, AT_FDCWD, newname); } @@ -2811,18 +2848,23 @@ void page_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie) } } -int __page_symlink(struct inode *inode, const char *symname, int len, - gfp_t gfp_mask) +/* + * The nofs argument instructs pagecache_write_begin to pass AOP_FLAG_NOFS + */ +int __page_symlink(struct inode *inode, const char *symname, int len, int nofs) { struct address_space *mapping = inode->i_mapping; struct page *page; void *fsdata; int err; char *kaddr; + unsigned int flags = AOP_FLAG_UNINTERRUPTIBLE; + if (nofs) + flags |= AOP_FLAG_NOFS; retry: err = pagecache_write_begin(NULL, mapping, 0, len-1, - AOP_FLAG_UNINTERRUPTIBLE, &page, &fsdata); + flags, &page, &fsdata); if (err) goto fail; @@ -2846,7 +2888,7 @@ fail: int page_symlink(struct inode *inode, const char *symname, int len) { return __page_symlink(inode, symname, len, - mapping_gfp_mask(inode->i_mapping)); + !(mapping_gfp_mask(inode->i_mapping) & __GFP_FS)); } const struct inode_operations page_symlink_inode_operations = { @@ -2887,10 +2929,3 @@ EXPORT_SYMBOL(vfs_symlink); EXPORT_SYMBOL(vfs_unlink); EXPORT_SYMBOL(dentry_unhash); EXPORT_SYMBOL(generic_readlink); - -/* to be mentioned only in INIT_TASK */ -struct fs_struct init_fs = { - .count = ATOMIC_INIT(1), - .lock = __RW_LOCK_UNLOCKED(init_fs.lock), - .umask = 0022, -};