diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/exec.c | 10 | ||||
| -rw-r--r-- | fs/namei.c | 143 | ||||
| -rw-r--r-- | fs/open.c | 10 |
3 files changed, 106 insertions, 57 deletions
diff --git a/fs/exec.c b/fs/exec.c index ad8798e26be9..c7f9b733406d 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -794,8 +794,14 @@ exit: struct file *open_exec(const char *name) { - struct filename tmp = { .name = name }; - return do_open_execat(AT_FDCWD, &tmp, 0); + struct filename *filename = getname_kernel(name); + struct file *f = ERR_CAST(filename); + + if (!IS_ERR(filename)) { + f = do_open_execat(AT_FDCWD, filename, 0); + putname(filename); + } + return f; } EXPORT_SYMBOL(open_exec); diff --git a/fs/namei.c b/fs/namei.c index bc35b02883bb..96ca11dea4a2 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -118,15 +118,6 @@ * POSIX.1 2.4: an empty pathname is invalid (ENOENT). * PATH_MAX includes the nul terminator --RR. */ -void final_putname(struct filename *name) -{ - if (name->separate) { - __putname(name->name); - kfree(name); - } else { - __putname(name); - } -} #define EMBEDDED_NAME_MAX (PATH_MAX - sizeof(struct filename)) @@ -145,6 +136,7 @@ getname_flags(const char __user *filename, int flags, int *empty) result = __getname(); if (unlikely(!result)) return ERR_PTR(-ENOMEM); + result->refcnt = 1; /* * First, try to embed the struct filename inside the names_cache @@ -179,6 +171,7 @@ recopy: } result->name = kname; result->separate = true; + result->refcnt = 1; max = PATH_MAX; goto recopy; } @@ -202,7 +195,7 @@ recopy: return result; error: - final_putname(result); + putname(result); return err; } @@ -212,43 +205,56 @@ getname(const char __user * filename) return getname_flags(filename, 0, NULL); } -/* - * The "getname_kernel()" interface doesn't do pathnames longer - * than EMBEDDED_NAME_MAX. Deal with it - you're a kernel user. - */ struct filename * getname_kernel(const char * filename) { struct filename *result; - char *kname; - int len; - - len = strlen(filename); - if (len >= EMBEDDED_NAME_MAX) - return ERR_PTR(-ENAMETOOLONG); + int len = strlen(filename) + 1; result = __getname(); if (unlikely(!result)) return ERR_PTR(-ENOMEM); - kname = (char *)result + sizeof(*result); - result->name = kname; + if (len <= EMBEDDED_NAME_MAX) { + result->name = (char *)(result) + sizeof(*result); + result->separate = false; + } else if (len <= PATH_MAX) { + struct filename *tmp; + + tmp = kmalloc(sizeof(*tmp), GFP_KERNEL); + if (unlikely(!tmp)) { + __putname(result); + return ERR_PTR(-ENOMEM); + } + tmp->name = (char *)result; + tmp->separate = true; + result = tmp; + } else { + __putname(result); + return ERR_PTR(-ENAMETOOLONG); + } + memcpy((char *)result->name, filename, len); result->uptr = NULL; result->aname = NULL; - result->separate = false; + result->refcnt = 1; + audit_getname(result); - strlcpy(kname, filename, EMBEDDED_NAME_MAX); return result; } -#ifdef CONFIG_AUDITSYSCALL void putname(struct filename *name) { - if (unlikely(!audit_dummy_context())) - return audit_putname(name); - final_putname(name); + BUG_ON(name->refcnt <= 0); + + if (--name->refcnt > 0) + return; + + if (name->separate) { + __putname(name->name); + kfree(name); + } else + __putname(name); } -#endif static int check_acl(struct inode *inode, int mask) { @@ -2036,31 +2042,47 @@ static int filename_lookup(int dfd, struct filename *name, static int do_path_lookup(int dfd, const char *name, unsigned int flags, struct nameidata *nd) { - struct filename filename = { .name = name }; + struct filename *filename = getname_kernel(name); + int retval = PTR_ERR(filename); - return filename_lookup(dfd, &filename, flags, nd); + if (!IS_ERR(filename)) { + retval = filename_lookup(dfd, filename, flags, nd); + putname(filename); + } + return retval; } /* does lookup, returns the object with parent locked */ struct dentry *kern_path_locked(const char *name, struct path *path) { + struct filename *filename = getname_kernel(name); struct nameidata nd; struct dentry *d; - int err = do_path_lookup(AT_FDCWD, name, LOOKUP_PARENT, &nd); - if (err) - return ERR_PTR(err); + int err; + + if (IS_ERR(filename)) + return ERR_CAST(filename); + + err = filename_lookup(AT_FDCWD, filename, LOOKUP_PARENT, &nd); + if (err) { + d = ERR_PTR(err); + goto out; + } if (nd.last_type != LAST_NORM) { path_put(&nd.path); - return ERR_PTR(-EINVAL); + d = ERR_PTR(-EINVAL); + goto out; } mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT); d = __lookup_hash(&nd.last, nd.path.dentry, 0); if (IS_ERR(d)) { mutex_unlock(&nd.path.dentry->d_inode->i_mutex); path_put(&nd.path); - return d; + goto out; } *path = nd.path; +out: + putname(filename); return d; } @@ -2351,13 +2373,17 @@ static int filename_mountpoint(int dfd, struct filename *s, struct path *path, unsigned int flags) { - int error = path_mountpoint(dfd, s->name, path, flags | LOOKUP_RCU); + int error; + if (IS_ERR(s)) + return PTR_ERR(s); + error = path_mountpoint(dfd, s->name, path, flags | LOOKUP_RCU); if (unlikely(error == -ECHILD)) error = path_mountpoint(dfd, s->name, path, flags); if (unlikely(error == -ESTALE)) error = path_mountpoint(dfd, s->name, path, flags | LOOKUP_REVAL); if (likely(!error)) audit_inode(s, path->dentry, 0); + putname(s); return error; } @@ -2379,21 +2405,14 @@ int user_path_mountpoint_at(int dfd, const char __user *name, unsigned int flags, struct path *path) { - struct filename *s = getname(name); - int error; - if (IS_ERR(s)) - return PTR_ERR(s); - error = filename_mountpoint(dfd, s, path, flags); - putname(s); - return error; + return filename_mountpoint(dfd, getname(name), path, flags); } int kern_path_mountpoint(int dfd, const char *name, struct path *path, unsigned int flags) { - struct filename s = {.name = name}; - return filename_mountpoint(dfd, &s, path, flags); + return filename_mountpoint(dfd, getname_kernel(name), path, flags); } EXPORT_SYMBOL(kern_path_mountpoint); @@ -3273,7 +3292,7 @@ struct file *do_file_open_root(struct dentry *dentry, struct vfsmount *mnt, { struct nameidata nd; struct file *file; - struct filename filename = { .name = name }; + struct filename *filename; int flags = op->lookup_flags | LOOKUP_ROOT; nd.root.mnt = mnt; @@ -3282,15 +3301,20 @@ struct file *do_file_open_root(struct dentry *dentry, struct vfsmount *mnt, if (d_is_symlink(dentry) && op->intent & LOOKUP_OPEN) return ERR_PTR(-ELOOP); - file = path_openat(-1, &filename, &nd, op, flags | LOOKUP_RCU); + filename = getname_kernel(name); + if (unlikely(IS_ERR(filename))) + return ERR_CAST(filename); + + file = path_openat(-1, filename, &nd, op, flags | LOOKUP_RCU); if (unlikely(file == ERR_PTR(-ECHILD))) - file = path_openat(-1, &filename, &nd, op, flags); + file = path_openat(-1, filename, &nd, op, flags); if (unlikely(file == ERR_PTR(-ESTALE))) - file = path_openat(-1, &filename, &nd, op, flags | LOOKUP_REVAL); + file = path_openat(-1, filename, &nd, op, flags | LOOKUP_REVAL); + putname(filename); return file; } -struct dentry *kern_path_create(int dfd, const char *pathname, +static struct dentry *filename_create(int dfd, struct filename *name, struct path *path, unsigned int lookup_flags) { struct dentry *dentry = ERR_PTR(-EEXIST); @@ -3305,7 +3329,7 @@ struct dentry *kern_path_create(int dfd, const char *pathname, */ lookup_flags &= LOOKUP_REVAL; - error = do_path_lookup(dfd, pathname, LOOKUP_PARENT|lookup_flags, &nd); + error = filename_lookup(dfd, name, LOOKUP_PARENT|lookup_flags, &nd); if (error) return ERR_PTR(error); @@ -3359,6 +3383,19 @@ out: path_put(&nd.path); return dentry; } + +struct dentry *kern_path_create(int dfd, const char *pathname, + struct path *path, unsigned int lookup_flags) +{ + struct filename *filename = getname_kernel(pathname); + struct dentry *res; + + if (IS_ERR(filename)) + return ERR_CAST(filename); + res = filename_create(dfd, filename, path, lookup_flags); + putname(filename); + return res; +} EXPORT_SYMBOL(kern_path_create); void done_path_create(struct path *path, struct dentry *dentry) @@ -3377,7 +3414,7 @@ struct dentry *user_path_create(int dfd, const char __user *pathname, struct dentry *res; if (IS_ERR(tmp)) return ERR_CAST(tmp); - res = kern_path_create(dfd, tmp->name, path, lookup_flags); + res = filename_create(dfd, tmp, path, lookup_flags); putname(tmp); return res; } diff --git a/fs/open.c b/fs/open.c index a293c2020676..33f9cbf2610b 100644 --- a/fs/open.c +++ b/fs/open.c @@ -968,8 +968,14 @@ struct file *file_open_name(struct filename *name, int flags, umode_t mode) */ struct file *filp_open(const char *filename, int flags, umode_t mode) { - struct filename name = {.name = filename}; - return file_open_name(&name, flags, mode); + struct filename *name = getname_kernel(filename); + struct file *file = ERR_CAST(name); + + if (!IS_ERR(name)) { + file = file_open_name(name, flags, mode); + putname(name); + } + return file; } EXPORT_SYMBOL(filp_open); |
