diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2011-03-14 18:56:51 -0400 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2011-03-14 19:12:20 -0400 |
| commit | f52e0c11305aa09ed56cad97ffc8f0cdc3d78b5d (patch) | |
| tree | b04070034f8a941fe5d7e9e1b335a02784686bd5 /fs/namei.c | |
| parent | 5fe0c2378884e68beb532f5890cc0e3539ac747b (diff) | |
| download | lwn-f52e0c11305aa09ed56cad97ffc8f0cdc3d78b5d.tar.gz lwn-f52e0c11305aa09ed56cad97ffc8f0cdc3d78b5d.zip | |
New AT_... flag: AT_EMPTY_PATH
For name_to_handle_at(2) we'll want both ...at()-style syscall that
would be usable for non-directory descriptors (with empty relative
pathname). Introduce new flag (AT_EMPTY_PATH) to deal with that and
corresponding LOOKUP_EMPTY; teach user_path_at() and path_init() to
deal with the latter.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs/namei.c')
| -rw-r--r-- | fs/namei.c | 29 |
1 files changed, 19 insertions, 10 deletions
diff --git a/fs/namei.c b/fs/namei.c index abc8d2df121c..83e92bab79a6 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -136,7 +136,7 @@ static int do_getname(const char __user *filename, char *page) return retval; } -char * getname(const char __user * filename) +static char *getname_flags(const char __user * filename, int flags) { char *tmp, *result; @@ -147,14 +147,21 @@ char * getname(const char __user * filename) result = tmp; if (retval < 0) { - __putname(tmp); - result = ERR_PTR(retval); + if (retval != -ENOENT || !(flags & LOOKUP_EMPTY)) { + __putname(tmp); + result = ERR_PTR(retval); + } } } audit_getname(result); return result; } +char *getname(const char __user * filename) +{ + return getname_flags(filename, 0); +} + #ifdef CONFIG_AUDITSYSCALL void putname(const char *name) { @@ -1544,13 +1551,15 @@ static int path_init(int dfd, const char *name, unsigned int flags, dentry = file->f_path.dentry; - retval = -ENOTDIR; - if (!S_ISDIR(dentry->d_inode->i_mode)) - goto fput_fail; + if (*name) { + retval = -ENOTDIR; + if (!S_ISDIR(dentry->d_inode->i_mode)) + goto fput_fail; - retval = file_permission(file, MAY_EXEC); - if (retval) - goto fput_fail; + retval = file_permission(file, MAY_EXEC); + if (retval) + goto fput_fail; + } nd->path = file->f_path; if (flags & LOOKUP_RCU) { @@ -1759,7 +1768,7 @@ int user_path_at(int dfd, const char __user *name, unsigned flags, struct path *path) { struct nameidata nd; - char *tmp = getname(name); + char *tmp = getname_flags(name, flags); int err = PTR_ERR(tmp); if (!IS_ERR(tmp)) { |