X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=fs%2Fnamei.c;h=bbc15c237558f82c7fbe2b661e55ee8fa1b9849d;hb=d8ae4601a4b7ea1fa17fa395c3468c0e144d1275;hp=4ea63ed5e79100d991e5f25656a263b04a29e611;hpb=a95164d979c5ca061f15bcaadc829c146693d4d9;p=safe%2Fjmp%2Flinux-2.6 diff --git a/fs/namei.c b/fs/namei.c index 4ea63ed..bbc15c2 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -186,7 +186,7 @@ int generic_permission(struct inode *inode, int mask, mask &= MAY_READ | MAY_WRITE | MAY_EXEC; - if (current->fsuid == inode->i_uid) + if (current_fsuid() == inode->i_uid) mode >>= 6; else { if (IS_POSIXACL(inode) && (mode & S_IRWXG) && check_acl) { @@ -212,8 +212,7 @@ int generic_permission(struct inode *inode, int mask, * Read/write DACs are always overridable. * Executable DACs are overridable if at least one exec bit is set. */ - if (!(mask & MAY_EXEC) || - (inode->i_mode & S_IXUGO) || S_ISDIR(inode->i_mode)) + if (!(mask & MAY_EXEC) || execute_ok(inode)) if (capable(CAP_DAC_OVERRIDE)) return 0; @@ -227,6 +226,16 @@ int generic_permission(struct inode *inode, int mask, return -EACCES; } +/** + * inode_permission - check for access rights to a given inode + * @inode: inode to check permission on + * @mask: right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC) + * + * Used to check for read/write/execute permissions on an inode. + * We use "fsuid" for this, letting us set arbitrary permissions + * for filesystem access without changing the "normal" uids which + * are used for other things. + */ int inode_permission(struct inode *inode, int mask) { int retval; @@ -248,24 +257,11 @@ int inode_permission(struct inode *inode, int mask) return -EACCES; } - /* Ordinary permission routines do not understand MAY_APPEND. */ - if (inode->i_op && inode->i_op->permission) { + if (inode->i_op->permission) retval = inode->i_op->permission(inode, mask); - if (!retval) { - /* - * Exec permission on a regular file is denied if none - * of the execute bits are set. - * - * This check should be done by the ->permission() - * method. - */ - if ((mask & MAY_EXEC) && S_ISREG(inode->i_mode) && - !(inode->i_mode & S_IXUGO)) - return -EACCES; - } - } else { + else retval = generic_permission(inode, mask, NULL); - } + if (retval) return retval; @@ -278,21 +274,6 @@ int inode_permission(struct inode *inode, int mask) } /** - * vfs_permission - check for access rights to a given path - * @nd: lookup result that describes the path - * @mask: right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC) - * - * Used to check for read/write/execute permissions on a path. - * We use "fsuid" for this, letting us set arbitrary permissions - * for filesystem access without changing the "normal" uids which - * are used for other things. - */ -int vfs_permission(struct nameidata *nd, int mask) -{ - return inode_permission(nd->path.dentry->d_inode, mask); -} - -/** * file_permission - check for additional access rights to a given file * @file: file to check access rights for * @mask: right to check for (%MAY_READ, %MAY_WRITE, %MAY_EXEC) @@ -302,7 +283,7 @@ int vfs_permission(struct nameidata *nd, int mask) * * Note: * Do not use this function in new code. All access checks should - * be done using vfs_permission(). + * be done using inode_permission(). */ int file_permission(struct file *file, int mask) { @@ -451,10 +432,10 @@ static int exec_permission_lite(struct inode *inode) { umode_t mode = inode->i_mode; - if (inode->i_op && inode->i_op->permission) + if (inode->i_op->permission) return -EAGAIN; - if (current->fsuid == inode->i_uid) + if (current_fsuid() == inode->i_uid) mode >>= 6; else if (in_group_p(inode->i_gid)) mode >>= 3; @@ -540,18 +521,6 @@ out_unlock: return result; } -/* SMP-safe */ -static __always_inline void -walk_init_root(const char *name, struct nameidata *nd) -{ - struct fs_struct *fs = current->fs; - - read_lock(&fs->lock); - nd->path = fs->root; - path_get(&fs->root); - read_unlock(&fs->lock); -} - /* * Wrapper to retry pathname resolution whenever the underlying * file system returns an ESTALE. @@ -589,9 +558,16 @@ static __always_inline int __vfs_follow_link(struct nameidata *nd, const char *l goto fail; if (*link == '/') { + struct fs_struct *fs = current->fs; + path_put(&nd->path); - walk_init_root(link, nd); + + read_lock(&fs->lock); + nd->path = fs->root; + path_get(&fs->root); + read_unlock(&fs->lock); } + res = link_path_walk(link, nd); if (nd->depth || res || nd->last_type!=LAST_NORM) return res; @@ -872,7 +848,8 @@ static int __link_path_walk(const char *name, struct nameidata *nd) nd->flags |= LOOKUP_CONTINUE; err = exec_permission_lite(inode); if (err == -EAGAIN) - err = vfs_permission(nd, MAY_EXEC); + err = inode_permission(nd->path.dentry->d_inode, + MAY_EXEC); if (err) break; @@ -931,9 +908,6 @@ static int __link_path_walk(const char *name, struct nameidata *nd) inode = next.dentry->d_inode; if (!inode) goto out_dput; - err = -ENOTDIR; - if (!inode->i_op) - goto out_dput; if (inode->i_op->follow_link) { err = do_follow_link(&next, nd); @@ -943,9 +917,6 @@ static int __link_path_walk(const char *name, struct nameidata *nd) inode = nd->path.dentry->d_inode; if (!inode) break; - err = -ENOTDIR; - if (!inode->i_op) - break; } else path_to_nameidata(&next, nd); err = -ENOTDIR; @@ -984,7 +955,7 @@ last_component: break; inode = next.dentry->d_inode; if ((lookup_flags & LOOKUP_FOLLOW) - && inode && inode->i_op && inode->i_op->follow_link) { + && inode && inode->i_op->follow_link) { err = do_follow_link(&next, nd); if (err) goto return_err; @@ -996,7 +967,7 @@ last_component: break; if (lookup_flags & LOOKUP_DIRECTORY) { err = -ENOTDIR; - if (!inode->i_op || !inode->i_op->lookup) + if (!inode->i_op->lookup) break; } goto return_base; @@ -1106,6 +1077,15 @@ int path_lookup(const char *name, unsigned int flags, return do_path_lookup(AT_FDCWD, name, flags, nd); } +int kern_path(const char *name, unsigned int flags, struct path *path) +{ + struct nameidata nd; + int res = do_path_lookup(AT_FDCWD, name, flags, &nd); + if (!res) + *path = nd.path; + return res; +} + /** * vfs_path_lookup - lookup a file path relative to a dentry-vfsmount pair * @dentry: pointer to dentry of the base directory @@ -1138,9 +1118,16 @@ int vfs_path_lookup(struct dentry *dentry, struct vfsmount *mnt, } -static int __path_lookup_intent_open(int dfd, const char *name, - unsigned int lookup_flags, struct nameidata *nd, - int open_flags, int create_mode) +/** + * path_lookup_open - lookup a file path with open intent + * @dfd: the directory to use as base, or AT_FDCWD + * @name: pointer to file name + * @lookup_flags: lookup intent flags + * @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) { struct file *filp = get_empty_filp(); int err; @@ -1149,7 +1136,7 @@ static int __path_lookup_intent_open(int dfd, const char *name, return -ENFILE; nd->intent.open.file = filp; nd->intent.open.flags = open_flags; - nd->intent.open.create_mode = create_mode; + nd->intent.open.create_mode = 0; err = do_path_lookup(dfd, name, lookup_flags|LOOKUP_OPEN, nd); if (IS_ERR(nd->intent.open.file)) { if (err == 0) { @@ -1161,38 +1148,6 @@ static int __path_lookup_intent_open(int dfd, const char *name, return err; } -/** - * path_lookup_open - lookup a file path with open intent - * @dfd: the directory to use as base, or AT_FDCWD - * @name: pointer to file name - * @lookup_flags: lookup intent flags - * @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) -{ - return __path_lookup_intent_open(dfd, name, lookup_flags, nd, - open_flags, 0); -} - -/** - * path_lookup_create - lookup a file path with open + create intent - * @dfd: the directory to use as base, or AT_FDCWD - * @name: pointer to file name - * @lookup_flags: lookup intent flags - * @nd: pointer to nameidata - * @open_flags: open intent flags - * @create_mode: create intent flags - */ -static int path_lookup_create(int dfd, const char *name, - unsigned int lookup_flags, struct nameidata *nd, - int open_flags, int create_mode) -{ - return __path_lookup_intent_open(dfd, name, lookup_flags|LOOKUP_CREATE, - nd, open_flags, create_mode); -} - static struct dentry *__lookup_hash(struct qstr *name, struct dentry *base, struct nameidata *nd) { @@ -1363,11 +1318,13 @@ static int user_path_parent(int dfd, const char __user *path, */ static inline int check_sticky(struct inode *dir, struct inode *inode) { + uid_t fsuid = current_fsuid(); + if (!(dir->i_mode & S_ISVTX)) return 0; - if (inode->i_uid == current->fsuid) + if (inode->i_uid == fsuid) return 0; - if (dir->i_uid == current->fsuid) + if (dir->i_uid == fsuid) return 0; return !capable(CAP_FOWNER); } @@ -1407,7 +1364,7 @@ static int may_delete(struct inode *dir,struct dentry *victim,int isdir) if (IS_APPEND(dir)) return -EPERM; if (check_sticky(dir, victim->d_inode)||IS_APPEND(victim->d_inode)|| - IS_IMMUTABLE(victim->d_inode)) + IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode)) return -EPERM; if (isdir) { if (!S_ISDIR(victim->d_inode->i_mode)) @@ -1470,20 +1427,18 @@ struct dentry *lock_rename(struct dentry *p1, struct dentry *p2) mutex_lock(&p1->d_inode->i_sb->s_vfs_rename_mutex); - for (p = p1; p->d_parent != p; p = p->d_parent) { - if (p->d_parent == p2) { - mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_PARENT); - mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_CHILD); - return p; - } + p = d_ancestor(p2, p1); + if (p) { + mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_PARENT); + mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_CHILD); + return p; } - for (p = p2; p->d_parent != p; p = p->d_parent) { - if (p->d_parent == p1) { - mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT); - mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_CHILD); - return p; - } + p = d_ancestor(p1, p2); + if (p) { + mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT); + mutex_lock_nested(&p2->d_inode->i_mutex, I_MUTEX_CHILD); + return p; } mutex_lock_nested(&p1->d_inode->i_mutex, I_MUTEX_PARENT); @@ -1508,7 +1463,7 @@ int vfs_create(struct inode *dir, struct dentry *dentry, int mode, if (error) return error; - if (!dir->i_op || !dir->i_op->create) + if (!dir->i_op->create) return -EACCES; /* shouldn't it be ENOSYS? */ mode &= S_IALLUGO; mode |= S_IFREG; @@ -1522,9 +1477,9 @@ int vfs_create(struct inode *dir, struct dentry *dentry, int mode, return error; } -int may_open(struct nameidata *nd, int acc_mode, int flag) +int may_open(struct path *path, int acc_mode, int flag) { - struct dentry *dentry = nd->path.dentry; + struct dentry *dentry = path->dentry; struct inode *inode = dentry->d_inode; int error; @@ -1545,13 +1500,13 @@ int may_open(struct nameidata *nd, int acc_mode, int flag) 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)) { - if (nd->path.mnt->mnt_flags & MNT_NODEV) + if (path->mnt->mnt_flags & MNT_NODEV) return -EACCES; flag &= ~O_TRUNC; } - error = vfs_permission(nd, acc_mode); + error = inode_permission(inode, acc_mode); if (error) return error; /* @@ -1585,6 +1540,9 @@ int may_open(struct nameidata *nd, int acc_mode, int flag) * Refuse to truncate files with mandatory locks held on them. */ error = locks_verify_locked(inode); + if (!error) + error = security_path_truncate(path, 0, + ATTR_MTIME|ATTR_CTIME|ATTR_OPEN); if (!error) { DQUOT_INIT(inode); @@ -1615,14 +1573,18 @@ static int __open_namei_create(struct nameidata *nd, struct path *path, if (!IS_POSIXACL(dir->d_inode)) mode &= ~current->fs->umask; + error = security_path_mknod(&nd->path, path->dentry, mode, 0); + if (error) + goto out_unlock; error = vfs_create(dir->d_inode, path->dentry, mode, nd); +out_unlock: mutex_unlock(&dir->d_inode->i_mutex); dput(nd->path.dentry); nd->path.dentry = path->dentry; if (error) return error; /* Don't check for write permission, don't truncate */ - return may_open(nd, 0, flag & ~O_TRUNC); + return may_open(&nd->path, 0, flag & ~O_TRUNC); } /* @@ -1702,8 +1664,7 @@ struct file *do_filp_open(int dfd, const char *pathname, /* * Create - we need to know the parent. */ - error = path_lookup_create(dfd, pathname, LOOKUP_PARENT, - &nd, flag, mode); + error = do_path_lookup(dfd, pathname, LOOKUP_PARENT, &nd); if (error) return ERR_PTR(error); @@ -1714,10 +1675,20 @@ struct file *do_filp_open(int dfd, const char *pathname, */ error = -EISDIR; if (nd.last_type != LAST_NORM || nd.last.name[nd.last.len]) - goto exit; + goto exit_parent; + error = -ENFILE; + filp = get_empty_filp(); + if (filp == NULL) + goto exit_parent; + nd.intent.open.file = filp; + nd.intent.open.flags = flag; + nd.intent.open.create_mode = mode; dir = nd.path.dentry; nd.flags &= ~LOOKUP_PARENT; + nd.flags |= LOOKUP_CREATE | LOOKUP_OPEN; + if (flag & O_EXCL) + nd.flags |= LOOKUP_EXCL; mutex_lock(&dir->d_inode->i_mutex); path.dentry = lookup_hash(&nd); path.mnt = nd.path.mnt; @@ -1775,7 +1746,7 @@ do_last: error = -ENOENT; if (!path.dentry->d_inode) goto exit_dput; - if (path.dentry->d_inode->i_op && path.dentry->d_inode->i_op->follow_link) + if (path.dentry->d_inode->i_op->follow_link) goto do_link; path_to_nameidata(&path, &nd); @@ -1799,7 +1770,7 @@ ok: if (error) goto exit; } - error = may_open(&nd, acc_mode, flag); + error = may_open(&nd.path, acc_mode, flag); if (error) { if (will_write) mnt_drop_write(nd.path.mnt); @@ -1822,6 +1793,7 @@ exit_dput: exit: if (!IS_ERR(nd.intent.open.file)) release_open_intent(&nd); +exit_parent: path_put(&nd.path); return ERR_PTR(error); @@ -1914,7 +1886,7 @@ struct dentry *lookup_create(struct nameidata *nd, int is_dir) if (nd->last_type != LAST_NORM) goto fail; nd->flags &= ~LOOKUP_PARENT; - nd->flags |= LOOKUP_CREATE; + nd->flags |= LOOKUP_CREATE | LOOKUP_EXCL; nd->intent.open.flags = O_EXCL; /* @@ -1955,7 +1927,7 @@ int vfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev) if ((S_ISCHR(mode) || S_ISBLK(mode)) && !capable(CAP_MKNOD)) return -EPERM; - if (!dir->i_op || !dir->i_op->mknod) + if (!dir->i_op->mknod) return -EPERM; error = devcgroup_inode_mknod(mode, dev); @@ -1990,8 +1962,8 @@ 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; @@ -2018,6 +1990,9 @@ asmlinkage long sys_mknodat(int dfd, const char __user *filename, int mode, error = mnt_want_write(nd.path.mnt); if (error) goto out_dput; + error = security_path_mknod(&nd.path, dentry, mode, dev); + if (error) + goto out_drop_write; switch (mode & S_IFMT) { case 0: case S_IFREG: error = vfs_create(nd.path.dentry->d_inode,dentry,mode,&nd); @@ -2030,6 +2005,7 @@ asmlinkage long sys_mknodat(int dfd, const char __user *filename, int mode, error = vfs_mknod(nd.path.dentry->d_inode,dentry,mode,0); break; } +out_drop_write: mnt_drop_write(nd.path.mnt); out_dput: dput(dentry); @@ -2041,7 +2017,7 @@ 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); } @@ -2053,7 +2029,7 @@ int vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) if (error) return error; - if (!dir->i_op || !dir->i_op->mkdir) + if (!dir->i_op->mkdir) return -EPERM; mode &= (S_IRWXUGO|S_ISVTX); @@ -2068,7 +2044,7 @@ int vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) 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; @@ -2089,7 +2065,11 @@ asmlinkage long sys_mkdirat(int dfd, const char __user *pathname, int mode) error = mnt_want_write(nd.path.mnt); if (error) goto out_dput; + error = security_path_mkdir(&nd.path, dentry, mode); + if (error) + goto out_drop_write; error = vfs_mkdir(nd.path.dentry->d_inode, dentry, mode); +out_drop_write: mnt_drop_write(nd.path.mnt); out_dput: dput(dentry); @@ -2101,7 +2081,7 @@ 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); } @@ -2140,7 +2120,7 @@ int vfs_rmdir(struct inode *dir, struct dentry *dentry) if (error) return error; - if (!dir->i_op || !dir->i_op->rmdir) + if (!dir->i_op->rmdir) return -EPERM; DQUOT_INIT(dir); @@ -2178,16 +2158,19 @@ static long do_rmdir(int dfd, const char __user *pathname) return error; switch(nd.last_type) { - case LAST_DOTDOT: - error = -ENOTEMPTY; - goto exit1; - case LAST_DOT: - error = -EINVAL; - goto exit1; - case LAST_ROOT: - error = -EBUSY; - goto exit1; + case LAST_DOTDOT: + error = -ENOTEMPTY; + goto exit1; + case LAST_DOT: + error = -EINVAL; + goto exit1; + case LAST_ROOT: + error = -EBUSY; + goto exit1; } + + nd.flags &= ~LOOKUP_PARENT; + mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT); dentry = lookup_hash(&nd); error = PTR_ERR(dentry); @@ -2196,7 +2179,11 @@ static long do_rmdir(int dfd, const char __user *pathname) error = mnt_want_write(nd.path.mnt); if (error) goto exit3; + error = security_path_rmdir(&nd.path, dentry); + if (error) + goto exit4; error = vfs_rmdir(nd.path.dentry->d_inode, dentry); +exit4: mnt_drop_write(nd.path.mnt); exit3: dput(dentry); @@ -2208,7 +2195,7 @@ exit1: return error; } -asmlinkage long sys_rmdir(const char __user *pathname) +SYSCALL_DEFINE1(rmdir, const char __user *, pathname) { return do_rmdir(AT_FDCWD, pathname); } @@ -2220,7 +2207,7 @@ int vfs_unlink(struct inode *dir, struct dentry *dentry) if (error) return error; - if (!dir->i_op || !dir->i_op->unlink) + if (!dir->i_op->unlink) return -EPERM; DQUOT_INIT(dir); @@ -2265,6 +2252,9 @@ static long do_unlinkat(int dfd, const char __user *pathname) error = -EISDIR; if (nd.last_type != LAST_NORM) goto exit1; + + nd.flags &= ~LOOKUP_PARENT; + mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT); dentry = lookup_hash(&nd); error = PTR_ERR(dentry); @@ -2278,7 +2268,11 @@ static long do_unlinkat(int dfd, const char __user *pathname) error = mnt_want_write(nd.path.mnt); if (error) goto exit2; + error = security_path_unlink(&nd.path, dentry); + if (error) + goto exit3; error = vfs_unlink(nd.path.dentry->d_inode, dentry); +exit3: mnt_drop_write(nd.path.mnt); exit2: dput(dentry); @@ -2297,7 +2291,7 @@ 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; @@ -2308,7 +2302,7 @@ 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); } @@ -2320,7 +2314,7 @@ int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname) if (error) return error; - if (!dir->i_op || !dir->i_op->symlink) + if (!dir->i_op->symlink) return -EPERM; error = security_inode_symlink(dir, dentry, oldname); @@ -2334,8 +2328,8 @@ int vfs_symlink(struct inode *dir, struct dentry *dentry, const char *oldname) 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; @@ -2359,7 +2353,11 @@ asmlinkage long sys_symlinkat(const char __user *oldname, error = mnt_want_write(nd.path.mnt); if (error) goto out_dput; + error = security_path_symlink(&nd.path, dentry, from); + if (error) + goto out_drop_write; error = vfs_symlink(nd.path.dentry->d_inode, dentry, from); +out_drop_write: mnt_drop_write(nd.path.mnt); out_dput: dput(dentry); @@ -2372,7 +2370,7 @@ 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); } @@ -2397,7 +2395,7 @@ int vfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_de */ if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) return -EPERM; - if (!dir->i_op || !dir->i_op->link) + if (!dir->i_op->link) return -EPERM; if (S_ISDIR(inode->i_mode)) return -EPERM; @@ -2424,9 +2422,8 @@ 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; @@ -2456,7 +2453,11 @@ asmlinkage long sys_linkat(int olddfd, const char __user *oldname, error = mnt_want_write(nd.path.mnt); if (error) goto out_dput; + error = security_path_link(old_path.dentry, &nd.path, new_dentry); + if (error) + goto out_drop_write; error = vfs_link(old_path.dentry, nd.path.dentry->d_inode, new_dentry); +out_drop_write: mnt_drop_write(nd.path.mnt); out_dput: dput(new_dentry); @@ -2471,7 +2472,7 @@ 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); } @@ -2600,7 +2601,7 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry, if (error) return error; - if (!old_dir->i_op || !old_dir->i_op->rename) + if (!old_dir->i_op->rename) return -EPERM; DQUOT_INIT(old_dir); @@ -2622,8 +2623,8 @@ 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; @@ -2654,6 +2655,10 @@ asmlinkage long sys_renameat(int olddfd, const char __user *oldname, if (newnd.last_type != LAST_NORM) goto exit2; + oldnd.flags &= ~LOOKUP_PARENT; + newnd.flags &= ~LOOKUP_PARENT; + newnd.flags |= LOOKUP_RENAME_TARGET; + trap = lock_rename(new_dir, old_dir); old_dentry = lookup_hash(&oldnd); @@ -2688,8 +2693,13 @@ asmlinkage long sys_renameat(int olddfd, const char __user *oldname, error = mnt_want_write(oldnd.path.mnt); if (error) goto exit5; + error = security_path_rename(&oldnd.path, old_dentry, + &newnd.path, new_dentry); + if (error) + goto exit6; error = vfs_rename(old_dir->d_inode, old_dentry, new_dir->d_inode, new_dentry); +exit6: mnt_drop_write(oldnd.path.mnt); exit5: dput(new_dentry); @@ -2707,7 +2717,7 @@ 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); } @@ -2759,13 +2769,16 @@ int vfs_follow_link(struct nameidata *nd, const char *link) /* get the link contents into pagecache */ static char *page_getlink(struct dentry * dentry, struct page **ppage) { - struct page * page; + char *kaddr; + struct page *page; struct address_space *mapping = dentry->d_inode->i_mapping; page = read_mapping_page(mapping, 0, NULL); if (IS_ERR(page)) return (char*)page; *ppage = page; - return kmap(page); + kaddr = kmap(page); + nd_terminate_link(kaddr, dentry->d_inode->i_size, PAGE_SIZE - 1); + return kaddr; } int page_readlink(struct dentry *dentry, char __user *buffer, int buflen) @@ -2797,18 +2810,23 @@ 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; @@ -2832,7 +2850,7 @@ 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 = { @@ -2855,9 +2873,9 @@ EXPORT_SYMBOL(__page_symlink); EXPORT_SYMBOL(page_symlink); EXPORT_SYMBOL(page_symlink_inode_operations); EXPORT_SYMBOL(path_lookup); +EXPORT_SYMBOL(kern_path); EXPORT_SYMBOL(vfs_path_lookup); EXPORT_SYMBOL(inode_permission); -EXPORT_SYMBOL(vfs_permission); EXPORT_SYMBOL(file_permission); EXPORT_SYMBOL(unlock_rename); EXPORT_SYMBOL(vfs_create); @@ -2873,3 +2891,10 @@ 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, +};