X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=fs%2Fnamei.c;h=868d0cb9d473a92ccdcbe640ac44f4daf24cce62;hb=6c5de280b6683d194ee60cf22dee56eef0b09619;hp=52517e0bbdde7fca6c740591566dd97829383676;hpb=a2c36b450ee68470836cb858c58a6ba3a52c5ec5;p=safe%2Fjmp%2Flinux-2.6 diff --git a/fs/namei.c b/fs/namei.c index 52517e0..868d0cb 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -19,7 +19,6 @@ #include #include #include -#include #include #include #include @@ -498,8 +497,6 @@ static int link_path_walk(const char *, struct nameidata *); static __always_inline int __vfs_follow_link(struct nameidata *nd, const char *link) { - int res = 0; - char *name; if (IS_ERR(link)) goto fail; @@ -510,22 +507,7 @@ static __always_inline int __vfs_follow_link(struct nameidata *nd, const char *l path_get(&nd->root); } - res = link_path_walk(link, nd); - if (nd->depth || res || nd->last_type!=LAST_NORM) - return res; - /* - * If it is an iterative symlinks resolution in open_namei() we - * have to copy the last component. And all that crap because of - * bloody create() on broken symlinks. Furrfu... - */ - name = __getname(); - if (unlikely(!name)) { - path_put(&nd->path); - return -ENOMEM; - } - strcpy(name, nd->last.name); - nd->last.name = name; - return 0; + return link_path_walk(link, nd); fail: path_put(&nd->path); return PTR_ERR(link); @@ -541,16 +523,17 @@ static void path_put_conditional(struct path *path, struct nameidata *nd) static inline void path_to_nameidata(struct path *path, struct nameidata *nd) { dput(nd->path.dentry); - if (nd->path.mnt != path->mnt) + if (nd->path.mnt != path->mnt) { mntput(nd->path.mnt); - nd->path.mnt = path->mnt; + nd->path.mnt = path->mnt; + } nd->path.dentry = path->dentry; } -static __always_inline int __do_follow_link(struct path *path, struct nameidata *nd) +static __always_inline int +__do_follow_link(struct path *path, struct nameidata *nd, void **p) { int error; - void *cookie; struct dentry *dentry = path->dentry; touch_atime(path->mnt, dentry); @@ -562,9 +545,9 @@ static __always_inline int __do_follow_link(struct path *path, struct nameidata } mntget(path->mnt); nd->last_type = LAST_BIND; - cookie = dentry->d_inode->i_op->follow_link(dentry, nd); - error = PTR_ERR(cookie); - if (!IS_ERR(cookie)) { + *p = dentry->d_inode->i_op->follow_link(dentry, nd); + error = PTR_ERR(*p); + if (!IS_ERR(*p)) { char *s = nd_get_link(nd); error = 0; if (s) @@ -574,8 +557,6 @@ static __always_inline int __do_follow_link(struct path *path, struct nameidata if (error) path_put(&nd->path); } - if (dentry->d_inode->i_op->put_link) - dentry->d_inode->i_op->put_link(dentry, nd, cookie); } return error; } @@ -589,6 +570,7 @@ static __always_inline int __do_follow_link(struct path *path, struct nameidata */ static inline int do_follow_link(struct path *path, struct nameidata *nd) { + void *cookie; int err = -ELOOP; if (current->link_count >= MAX_NESTED_LINKS) goto loop; @@ -602,7 +584,9 @@ static inline int do_follow_link(struct path *path, struct nameidata *nd) current->link_count++; current->total_link_count++; nd->depth++; - err = __do_follow_link(path, nd); + err = __do_follow_link(path, nd, &cookie); + if (!IS_ERR(cookie) && path->dentry->d_inode->i_op->put_link) + path->dentry->d_inode->i_op->put_link(path->dentry, nd, cookie); path_put(path); current->link_count--; nd->depth--; @@ -1375,22 +1359,6 @@ static inline int may_create(struct inode *dir, struct dentry *child) return inode_permission(dir, MAY_WRITE | MAY_EXEC); } -/* - * O_DIRECTORY translates into forcing a directory lookup. - */ -static inline int lookup_flags(unsigned int f) -{ - unsigned long retval = LOOKUP_FOLLOW; - - if (f & O_NOFOLLOW) - retval &= ~LOOKUP_FOLLOW; - - if (f & O_DIRECTORY) - retval |= LOOKUP_DIRECTORY; - - return retval; -} - /* * p1 and p2 should be directories on the same fs. */ @@ -1448,7 +1416,6 @@ int vfs_create(struct inode *dir, struct dentry *dentry, int mode, error = security_inode_create(dir, dentry, mode); if (error) return error; - vfs_dq_init(dir); error = dir->i_op->create(dir, dentry, mode, nd); if (!error) fsnotify_create(dir, dentry); @@ -1591,13 +1558,13 @@ static int open_will_truncate(int flag, struct inode *inode) } static struct file *finish_open(struct nameidata *nd, - int open_flag, int flag, int acc_mode) + int open_flag, int acc_mode) { struct file *filp; int will_truncate; int error; - will_truncate = open_will_truncate(flag, nd->path.dentry->d_inode); + will_truncate = open_will_truncate(open_flag, nd->path.dentry->d_inode); if (will_truncate) { error = mnt_want_write(nd->path.mnt); if (error) @@ -1618,9 +1585,6 @@ static struct file *finish_open(struct nameidata *nd, } } if (!IS_ERR(filp)) { - if (acc_mode & MAY_WRITE) - vfs_dq_init(nd->path.dentry->d_inode); - if (will_truncate) { error = handle_truncate(&nd->path); if (error) { @@ -1646,20 +1610,62 @@ exit: } static struct file *do_last(struct nameidata *nd, struct path *path, - int open_flag, int flag, int acc_mode, - int mode, const char *pathname, - int *is_link) + int open_flag, int acc_mode, + int mode, const char *pathname) { struct dentry *dir = nd->path.dentry; struct file *filp; - int error; + int error = -EISDIR; + + switch (nd->last_type) { + case LAST_DOTDOT: + follow_dotdot(nd); + dir = nd->path.dentry; + case LAST_DOT: + if (nd->path.mnt->mnt_sb->s_type->fs_flags & FS_REVAL_DOT) { + if (!dir->d_op->d_revalidate(dir, nd)) { + error = -ESTALE; + goto exit; + } + } + /* fallthrough */ + case LAST_ROOT: + if (open_flag & O_CREAT) + goto exit; + /* fallthrough */ + case LAST_BIND: + audit_inode(pathname, dir); + goto ok; + } - *is_link = 0; + /* trailing slashes? */ + if (nd->last.name[nd->last.len]) { + if (open_flag & O_CREAT) + goto exit; + nd->flags |= LOOKUP_DIRECTORY | LOOKUP_FOLLOW; + } - error = -EISDIR; - if (nd->last_type != LAST_NORM || nd->last.name[nd->last.len]) - goto exit; + /* just plain open? */ + if (!(open_flag & O_CREAT)) { + error = do_lookup(nd, &nd->last, path); + if (error) + goto exit; + error = -ENOENT; + if (!path->dentry->d_inode) + goto exit_dput; + if (path->dentry->d_inode->i_op->follow_link) + return NULL; + error = -ENOTDIR; + if (nd->flags & LOOKUP_DIRECTORY) { + if (!path->dentry->d_inode->i_op->lookup) + goto exit_dput; + } + path_to_nameidata(path, nd); + audit_inode(pathname, nd->path.dentry); + goto ok; + } + /* OK, it's O_CREAT */ mutex_lock(&dir->d_inode->i_mutex); path->dentry = lookup_hash(nd); @@ -1712,28 +1718,28 @@ static struct file *do_last(struct nameidata *nd, struct path *path, audit_inode(pathname, path->dentry); error = -EEXIST; - if (flag & O_EXCL) + if (open_flag & O_EXCL) goto exit_dput; if (__follow_mount(path)) { error = -ELOOP; - if (flag & O_NOFOLLOW) + if (open_flag & O_NOFOLLOW) goto exit_dput; } error = -ENOENT; if (!path->dentry->d_inode) goto exit_dput; - if (path->dentry->d_inode->i_op->follow_link) { - *is_link = 1; + + if (path->dentry->d_inode->i_op->follow_link) return NULL; - } path_to_nameidata(path, nd); error = -EISDIR; if (S_ISDIR(path->dentry->d_inode->i_mode)) goto exit; - filp = finish_open(nd, open_flag, flag, acc_mode); +ok: + filp = finish_open(nd, open_flag, acc_mode); return filp; exit_mutex_unlock: @@ -1762,7 +1768,9 @@ struct file *do_filp_open(int dfd, const char *pathname, int count = 0; int flag = open_to_namei_flags(open_flag); int force_reval = 0; - int is_link; + + if (!(open_flag & O_CREAT)) + mode = 0; /* * O_SYNC is implemented as __O_SYNC|O_DSYNC. As many places only @@ -1777,56 +1785,29 @@ struct file *do_filp_open(int dfd, const char *pathname, acc_mode = MAY_OPEN | ACC_MODE(open_flag); /* O_TRUNC implies we need access checks for write permissions */ - if (flag & O_TRUNC) + if (open_flag & O_TRUNC) acc_mode |= MAY_WRITE; /* Allow the LSM permission hook to distinguish append access from general write access. */ - if (flag & O_APPEND) + if (open_flag & O_APPEND) acc_mode |= MAY_APPEND; - /* - * The simplest case - just a plain lookup. - */ - if (!(flag & O_CREAT)) { - filp = get_empty_filp(); - - if (filp == NULL) - return ERR_PTR(-ENFILE); - nd.intent.open.file = filp; - filp->f_flags = open_flag; - nd.intent.open.flags = flag; - nd.intent.open.create_mode = 0; - error = do_path_lookup(dfd, pathname, - lookup_flags(flag)|LOOKUP_OPEN, &nd); - if (IS_ERR(nd.intent.open.file)) { - if (error == 0) { - error = PTR_ERR(nd.intent.open.file); - path_put(&nd.path); - } - } else if (error) - release_open_intent(&nd); - if (error) - return ERR_PTR(error); - goto ok; - } - - /* - * Create - we need to know the parent. - */ + /* find the parent */ reval: error = path_init(dfd, pathname, LOOKUP_PARENT, &nd); if (error) return ERR_PTR(error); if (force_reval) nd.flags |= LOOKUP_REVAL; - error = path_walk(pathname, &nd); + + current->total_link_count = 0; + error = link_path_walk(pathname, &nd); if (error) { - if (nd.root.mnt) - path_put(&nd.root); - return ERR_PTR(error); + filp = ERR_PTR(error); + goto out; } - if (unlikely(!audit_dummy_context())) + if (unlikely(!audit_dummy_context()) && (open_flag & O_CREAT)) audit_inode(pathname, nd.path.dentry); /* @@ -1842,80 +1823,76 @@ reval: nd.intent.open.flags = flag; nd.intent.open.create_mode = mode; nd.flags &= ~LOOKUP_PARENT; - nd.flags |= LOOKUP_CREATE | LOOKUP_OPEN; - if (flag & O_EXCL) - nd.flags |= LOOKUP_EXCL; - filp = do_last(&nd, &path, open_flag, flag, acc_mode, mode, - pathname, &is_link); - if (is_link) - goto do_link; - if (nd.root.mnt) - path_put(&nd.root); - return filp; - -ok: - filp = finish_open(&nd, open_flag, flag, acc_mode); + nd.flags |= LOOKUP_OPEN; + if (open_flag & O_CREAT) { + nd.flags |= LOOKUP_CREATE; + if (open_flag & O_EXCL) + nd.flags |= LOOKUP_EXCL; + } + if (open_flag & O_DIRECTORY) + nd.flags |= LOOKUP_DIRECTORY; + if (!(open_flag & O_NOFOLLOW)) + nd.flags |= LOOKUP_FOLLOW; + filp = do_last(&nd, &path, open_flag, acc_mode, mode, pathname); + while (unlikely(!filp)) { /* trailing symlink */ + struct path holder; + struct inode *inode = path.dentry->d_inode; + void *cookie; + error = -ELOOP; + /* S_ISDIR part is a temporary automount kludge */ + if (!(nd.flags & LOOKUP_FOLLOW) && !S_ISDIR(inode->i_mode)) + goto exit_dput; + if (count++ == 32) + goto exit_dput; + /* + * This is subtle. Instead of calling do_follow_link() we do + * the thing by hands. The reason is that this way we have zero + * link_count and path_walk() (called from ->follow_link) + * honoring LOOKUP_PARENT. After that we have the parent and + * last component, i.e. we are in the same situation as after + * the first path_walk(). Well, almost - if the last component + * is normal we get its copy stored in nd->last.name and we will + * have to putname() it when we are done. Procfs-like symlinks + * just set LAST_BIND. + */ + nd.flags |= LOOKUP_PARENT; + error = security_inode_follow_link(path.dentry, &nd); + if (error) + goto exit_dput; + error = __do_follow_link(&path, &nd, &cookie); + if (unlikely(error)) { + /* nd.path had been dropped */ + if (!IS_ERR(cookie) && inode->i_op->put_link) + inode->i_op->put_link(path.dentry, &nd, cookie); + path_put(&path); + release_open_intent(&nd); + filp = ERR_PTR(error); + goto out; + } + holder = path; + nd.flags &= ~LOOKUP_PARENT; + filp = do_last(&nd, &path, open_flag, acc_mode, mode, pathname); + if (inode->i_op->put_link) + inode->i_op->put_link(holder.dentry, &nd, cookie); + path_put(&holder); + } +out: if (nd.root.mnt) path_put(&nd.root); + if (filp == ERR_PTR(-ESTALE) && !force_reval) { + force_reval = 1; + goto reval; + } return filp; exit_dput: path_put_conditional(&path, &nd); -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); - -do_link: - error = -ELOOP; - if ((flag & O_NOFOLLOW) || count++ == 32) - goto exit_dput; - /* - * This is subtle. Instead of calling do_follow_link() we do the - * thing by hands. The reason is that this way we have zero link_count - * and path_walk() (called from ->follow_link) honoring LOOKUP_PARENT. - * After that we have the parent and last component, i.e. - * we are in the same situation as after the first path_walk(). - * Well, almost - if the last component is normal we get its copy - * stored in nd->last.name and we will have to putname() it when we - * are done. Procfs-like symlinks just set LAST_BIND. - */ - nd.flags |= LOOKUP_PARENT; - error = security_inode_follow_link(path.dentry, &nd); - if (error) - goto exit_dput; - error = __do_follow_link(&path, &nd); - path_put(&path); - if (error) { - /* Does someone understand code flow here? Or it is only - * me so stupid? Anathema to whoever designed this non-sense - * with "intent.open". - */ - release_open_intent(&nd); - if (nd.root.mnt) - path_put(&nd.root); - if (error == -ESTALE && !force_reval) { - force_reval = 1; - goto reval; - } - return ERR_PTR(error); - } - nd.flags &= ~LOOKUP_PARENT; - if (nd.last_type == LAST_BIND) - goto ok; - filp = do_last(&nd, &path, open_flag, flag, acc_mode, mode, - pathname, &is_link); - if (nd.last_type == LAST_NORM) - __putname(nd.last.name); - if (is_link) - goto do_link; - if (nd.root.mnt) - path_put(&nd.root); - return filp; + filp = ERR_PTR(error); + goto out; } /** @@ -2009,7 +1986,6 @@ int vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) if (error) return error; - vfs_dq_init(dir); error = dir->i_op->mknod(dir, dentry, mode, dev); if (!error) fsnotify_create(dir, dentry); @@ -2108,7 +2084,6 @@ int vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) if (error) return error; - vfs_dq_init(dir); error = dir->i_op->mkdir(dir, dentry, mode); if (!error) fsnotify_mkdir(dir, dentry); @@ -2194,8 +2169,6 @@ int vfs_rmdir(struct inode *dir, struct dentry *dentry) if (!dir->i_op->rmdir) return -EPERM; - vfs_dq_init(dir); - mutex_lock(&dentry->d_inode->i_mutex); dentry_unhash(dentry); if (d_mountpoint(dentry)) @@ -2204,8 +2177,10 @@ int vfs_rmdir(struct inode *dir, struct dentry *dentry) error = security_inode_rmdir(dir, dentry); if (!error) { error = dir->i_op->rmdir(dir, dentry); - if (!error) + if (!error) { dentry->d_inode->i_flags |= S_DEAD; + dont_mount(dentry); + } } } mutex_unlock(&dentry->d_inode->i_mutex); @@ -2281,8 +2256,6 @@ int vfs_unlink(struct inode *dir, struct dentry *dentry) if (!dir->i_op->unlink) return -EPERM; - vfs_dq_init(dir); - mutex_lock(&dentry->d_inode->i_mutex); if (d_mountpoint(dentry)) error = -EBUSY; @@ -2291,7 +2264,7 @@ int vfs_unlink(struct inode *dir, struct dentry *dentry) if (!error) { error = dir->i_op->unlink(dir, dentry); if (!error) - dentry->d_inode->i_flags |= S_DEAD; + dont_mount(dentry); } } mutex_unlock(&dentry->d_inode->i_mutex); @@ -2395,7 +2368,6 @@ int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname) if (error) return error; - vfs_dq_init(dir); error = dir->i_op->symlink(dir, dentry, oldname); if (!error) fsnotify_create(dir, dentry); @@ -2479,7 +2451,6 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de return error; mutex_lock(&inode->i_mutex); - vfs_dq_init(dir); error = dir->i_op->link(old_dentry, dir, new_dentry); mutex_unlock(&inode->i_mutex); if (!error) @@ -2580,7 +2551,7 @@ SYSCALL_DEFINE2(link, const char __user *, oldname, const char __user *, newname * e) conversion from fhandle to dentry may come in the wrong moment - when * we are removing the target. Solution: we will have to grab ->i_mutex * in the fhandle_to_dentry code. [FIXME - current nfsfh.c relies on - * ->i_mutex on parents, which works but leads to some truely excessive + * ->i_mutex on parents, which works but leads to some truly excessive * locking]. */ static int vfs_rename_dir(struct inode *old_dir, struct dentry *old_dentry, @@ -2604,17 +2575,20 @@ static int vfs_rename_dir(struct inode *old_dir, struct dentry *old_dentry, return error; target = new_dentry->d_inode; - if (target) { + if (target) mutex_lock(&target->i_mutex); - dentry_unhash(new_dentry); - } if (d_mountpoint(old_dentry)||d_mountpoint(new_dentry)) error = -EBUSY; - else + else { + if (target) + dentry_unhash(new_dentry); error = old_dir->i_op->rename(old_dir, old_dentry, new_dir, new_dentry); + } if (target) { - if (!error) + if (!error) { target->i_flags |= S_DEAD; + dont_mount(new_dentry); + } mutex_unlock(&target->i_mutex); if (d_unhashed(new_dentry)) d_rehash(new_dentry); @@ -2646,7 +2620,7 @@ static int vfs_rename_other(struct inode *old_dir, struct dentry *old_dentry, error = old_dir->i_op->rename(old_dir, old_dentry, new_dir, new_dentry); if (!error) { if (target) - target->i_flags |= S_DEAD; + dont_mount(new_dentry); if (!(old_dir->i_sb->s_type->fs_flags & FS_RENAME_DOES_D_MOVE)) d_move(old_dentry, new_dentry); } @@ -2680,9 +2654,6 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry, if (!old_dir->i_op->rename) return -EPERM; - vfs_dq_init(old_dir); - vfs_dq_init(new_dir); - old_name = fsnotify_oldname_init(old_dentry->d_name.name); if (is_dir)