From 921a1650de9eed40dd64d681aba4a4d98856f289 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Fri, 20 Jul 2012 01:15:31 +0400
Subject: new helper: done_path_create()
releases what needs to be released after {kern,user}_path_create()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
net/unix/af_unix.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)
(limited to 'net/unix')
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 641f2e47f16..e8239540683 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -887,8 +887,9 @@ out_mknod_drop_write:
mnt_drop_write(path.mnt);
if (err)
goto out_mknod_dput;
- mutex_unlock(&path.dentry->d_inode->i_mutex);
- dput(path.dentry);
+ mntget(path.mnt);
+ dget(dentry);
+ done_path_create(&path, dentry);
path.dentry = dentry;
addr->hash = UNIX_HASH_SIZE;
@@ -923,9 +924,7 @@ out:
return err;
out_mknod_dput:
- dput(dentry);
- mutex_unlock(&path.dentry->d_inode->i_mutex);
- path_put(&path);
+ done_path_create(&path, dentry);
out_mknod_parent:
if (err == -EEXIST)
err = -EADDRINUSE;
--
cgit v1.2.3-70-g09d2
From a8104a9fcdeb82e22d7acd55fca20746581067d3 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Fri, 20 Jul 2012 02:25:00 +0400
Subject: pull mnt_want_write()/mnt_drop_write() into
kern_path_create()/done_path_create() resp.
One side effect - attempt to create a cross-device link on a read-only fs fails
with EROFS instead of EXDEV now. Makes more sense, POSIX allows, etc.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
fs/namei.c | 57 ++++++++++++++++---------------------------------
fs/ocfs2/refcounttree.c | 7 ------
net/unix/af_unix.c | 4 ----
3 files changed, 18 insertions(+), 50 deletions(-)
(limited to 'net/unix')
diff --git a/fs/namei.c b/fs/namei.c
index cf362dc9d1f..a3fb78fd70d 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2865,10 +2865,11 @@ struct dentry *kern_path_create(int dfd, const char *pathname, struct path *path
mutex_lock_nested(&nd.path.dentry->d_inode->i_mutex, I_MUTEX_PARENT);
dentry = lookup_hash(&nd);
if (IS_ERR(dentry))
- goto fail;
+ goto unlock;
+ error = -EEXIST;
if (dentry->d_inode)
- goto eexist;
+ goto fail;
/*
* Special case - lookup gave negative, but... we had foo/bar/
* From the vfs_mknod() POV we just have a negative dentry -
@@ -2876,16 +2877,18 @@ struct dentry *kern_path_create(int dfd, const char *pathname, struct path *path
* been asking for (non-existent) directory. -ENOENT for you.
*/
if (unlikely(!is_dir && nd.last.name[nd.last.len])) {
- dput(dentry);
- dentry = ERR_PTR(-ENOENT);
+ error = -ENOENT;
goto fail;
}
+ error = mnt_want_write(nd.path.mnt);
+ if (error)
+ goto fail;
*path = nd.path;
return dentry;
-eexist:
- dput(dentry);
- dentry = ERR_PTR(-EEXIST);
fail:
+ dput(dentry);
+ dentry = ERR_PTR(error);
+unlock:
mutex_unlock(&nd.path.dentry->d_inode->i_mutex);
out:
path_put(&nd.path);
@@ -2897,6 +2900,7 @@ void done_path_create(struct path *path, struct dentry *dentry)
{
dput(dentry);
mutex_unlock(&path->dentry->d_inode->i_mutex);
+ mnt_drop_write(path->mnt);
path_put(path);
}
EXPORT_SYMBOL(done_path_create);
@@ -2974,12 +2978,9 @@ SYSCALL_DEFINE4(mknodat, int, dfd, const char __user *, filename, umode_t, mode,
if (!IS_POSIXACL(path.dentry->d_inode))
mode &= ~current_umask();
- error = mnt_want_write(path.mnt);
- if (error)
- goto out_dput;
error = security_path_mknod(&path, dentry, mode, dev);
if (error)
- goto out_drop_write;
+ goto out;
switch (mode & S_IFMT) {
case 0: case S_IFREG:
error = vfs_create(path.dentry->d_inode,dentry,mode,true);
@@ -2992,11 +2993,8 @@ SYSCALL_DEFINE4(mknodat, int, dfd, const char __user *, filename, umode_t, mode,
error = vfs_mknod(path.dentry->d_inode,dentry,mode,0);
break;
}
-out_drop_write:
- mnt_drop_write(path.mnt);
-out_dput:
+out:
done_path_create(&path, dentry);
-
return error;
}
@@ -3042,16 +3040,9 @@ SYSCALL_DEFINE3(mkdirat, int, dfd, const char __user *, pathname, umode_t, mode)
if (!IS_POSIXACL(path.dentry->d_inode))
mode &= ~current_umask();
- error = mnt_want_write(path.mnt);
- if (error)
- goto out_dput;
error = security_path_mkdir(&path, dentry, mode);
- if (error)
- goto out_drop_write;
- error = vfs_mkdir(path.dentry->d_inode, dentry, mode);
-out_drop_write:
- mnt_drop_write(path.mnt);
-out_dput:
+ if (!error)
+ error = vfs_mkdir(path.dentry->d_inode, dentry, mode);
done_path_create(&path, dentry);
return error;
}
@@ -3326,16 +3317,9 @@ SYSCALL_DEFINE3(symlinkat, const char __user *, oldname,
if (IS_ERR(dentry))
goto out_putname;
- error = mnt_want_write(path.mnt);
- if (error)
- goto out_dput;
error = security_path_symlink(&path, dentry, from);
- if (error)
- goto out_drop_write;
- error = vfs_symlink(path.dentry->d_inode, dentry, from);
-out_drop_write:
- mnt_drop_write(path.mnt);
-out_dput:
+ if (!error)
+ error = vfs_symlink(path.dentry->d_inode, dentry, from);
done_path_create(&path, dentry);
out_putname:
putname(from);
@@ -3436,15 +3420,10 @@ SYSCALL_DEFINE5(linkat, int, olddfd, const char __user *, oldname,
error = -EXDEV;
if (old_path.mnt != new_path.mnt)
goto out_dput;
- error = mnt_want_write(new_path.mnt);
- if (error)
- goto out_dput;
error = security_path_link(old_path.dentry, &new_path, new_dentry);
if (error)
- goto out_drop_write;
+ goto out_dput;
error = vfs_link(old_path.dentry, new_path.dentry->d_inode, new_dentry);
-out_drop_write:
- mnt_drop_write(new_path.mnt);
out_dput:
done_path_create(&new_path, new_dentry);
out:
diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c
index 23cf78f6850..30a055049e1 100644
--- a/fs/ocfs2/refcounttree.c
+++ b/fs/ocfs2/refcounttree.c
@@ -4466,16 +4466,9 @@ int ocfs2_reflink_ioctl(struct inode *inode,
goto out_dput;
}
- error = mnt_want_write(new_path.mnt);
- if (error) {
- mlog_errno(error);
- goto out_dput;
- }
-
error = ocfs2_vfs_reflink(old_path.dentry,
new_path.dentry->d_inode,
new_dentry, preserve);
- mnt_drop_write(new_path.mnt);
out_dput:
done_path_create(&new_path, new_dentry);
out:
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index e8239540683..88ab72820b9 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -876,15 +876,11 @@ static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
*/
mode = S_IFSOCK |
(SOCK_INODE(sock)->i_mode & ~current_umask());
- err = mnt_want_write(path.mnt);
- if (err)
- goto out_mknod_dput;
err = security_path_mknod(&path, dentry, mode, 0);
if (err)
goto out_mknod_drop_write;
err = vfs_mknod(path.dentry->d_inode, dentry, mode, 0);
out_mknod_drop_write:
- mnt_drop_write(path.mnt);
if (err)
goto out_mknod_dput;
mntget(path.mnt);
--
cgit v1.2.3-70-g09d2
From faf02010290e202e275c1bf94ca9dd808bf85607 Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Fri, 20 Jul 2012 02:37:29 +0400
Subject: clean unix_bind() up a bit
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
net/unix/af_unix.c | 88 ++++++++++++++++++++++++++----------------------------
1 file changed, 43 insertions(+), 45 deletions(-)
(limited to 'net/unix')
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 88ab72820b9..b7667f81c49 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -814,6 +814,34 @@ fail:
return NULL;
}
+static int unix_mknod(const char *sun_path, umode_t mode, struct path *res)
+{
+ struct dentry *dentry;
+ struct path path;
+ int err = 0;
+ /*
+ * Get the parent directory, calculate the hash for last
+ * component.
+ */
+ dentry = kern_path_create(AT_FDCWD, sun_path, &path, 0);
+ err = PTR_ERR(dentry);
+ if (IS_ERR(dentry))
+ return err;
+
+ /*
+ * All right, let's create it.
+ */
+ err = security_path_mknod(&path, dentry, mode, 0);
+ if (!err) {
+ err = vfs_mknod(path.dentry->d_inode, dentry, mode, 0);
+ if (!err) {
+ res->mnt = mntget(path.mnt);
+ res->dentry = dget(dentry);
+ }
+ }
+ done_path_create(&path, dentry);
+ return err;
+}
static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
{
@@ -822,8 +850,6 @@ static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
struct unix_sock *u = unix_sk(sk);
struct sockaddr_un *sunaddr = (struct sockaddr_un *)uaddr;
char *sun_path = sunaddr->sun_path;
- struct dentry *dentry = NULL;
- struct path path;
int err;
unsigned int hash;
struct unix_address *addr;
@@ -860,40 +886,23 @@ static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
atomic_set(&addr->refcnt, 1);
if (sun_path[0]) {
- umode_t mode;
- err = 0;
- /*
- * Get the parent directory, calculate the hash for last
- * component.
- */
- dentry = kern_path_create(AT_FDCWD, sun_path, &path, 0);
- err = PTR_ERR(dentry);
- if (IS_ERR(dentry))
- goto out_mknod_parent;
-
- /*
- * All right, let's create it.
- */
- mode = S_IFSOCK |
+ struct path path;
+ umode_t mode = S_IFSOCK |
(SOCK_INODE(sock)->i_mode & ~current_umask());
- err = security_path_mknod(&path, dentry, mode, 0);
- if (err)
- goto out_mknod_drop_write;
- err = vfs_mknod(path.dentry->d_inode, dentry, mode, 0);
-out_mknod_drop_write:
- if (err)
- goto out_mknod_dput;
- mntget(path.mnt);
- dget(dentry);
- done_path_create(&path, dentry);
- path.dentry = dentry;
-
+ err = unix_mknod(sun_path, mode, &path);
+ if (err) {
+ if (err == -EEXIST)
+ err = -EADDRINUSE;
+ unix_release_addr(addr);
+ goto out_up;
+ }
addr->hash = UNIX_HASH_SIZE;
- }
-
- spin_lock(&unix_table_lock);
-
- if (!sun_path[0]) {
+ hash = path.dentry->d_inode->i_ino & (UNIX_HASH_SIZE-1);
+ spin_lock(&unix_table_lock);
+ u->path = path;
+ list = &unix_socket_table[hash];
+ } else {
+ spin_lock(&unix_table_lock);
err = -EADDRINUSE;
if (__unix_find_socket_byname(net, sunaddr, addr_len,
sk->sk_type, hash)) {
@@ -902,9 +911,6 @@ out_mknod_drop_write:
}
list = &unix_socket_table[addr->hash];
- } else {
- list = &unix_socket_table[dentry->d_inode->i_ino & (UNIX_HASH_SIZE-1)];
- u->path = path;
}
err = 0;
@@ -918,14 +924,6 @@ out_up:
mutex_unlock(&u->readlock);
out:
return err;
-
-out_mknod_dput:
- done_path_create(&path, dentry);
-out_mknod_parent:
- if (err == -EEXIST)
- err = -EADDRINUSE;
- unix_release_addr(addr);
- goto out_up;
}
static void unix_state_double_lock(struct sock *sk1, struct sock *sk2)
--
cgit v1.2.3-70-g09d2