Re: [RFC PATCH 1/2] unix sockets: add ability for search for peer from passed root

2012-08-10 Thread Stanislav Kinsbursky

10.08.2012 22:10, J. Bruce Fields пишет:

On Fri, Aug 10, 2012 at 04:57:30PM +0400, Stanislav Kinsbursky wrote:

This helper is used stream sockets yet.
All is simple: if non-NULL struct path was passed to unix_find_other(), then
vfs_path_lookup() is called instead of kern_path().

I'm having some trouble parsing the changelog.  Maybe something like?:

unix sockets: add ability to look up using passed-in root

Export a unix_stream_connect_root() helper that allows a caller
to optionally pass in a root path, in which case the lookup will
be done relative to the given path instead of the current
working directory.


Yep, your variant is much better. Thanks.



I guess this is a question for the networking people, but: will it cause
problems to have sunrpc calling directly into the unix socket code?

(And if so, what would be the alternative: define some variant of
sockaddr_un that includes the root path?  Something better?)


That was my first idea. But there are problems with this solution (add 
root path to sockaddr_un) :
1) sockaddr_un size will change. I don't know, how this will affect 
user-space. Of course, we can introduce something like:


struct sockaddr_un_kern {
struct sockaddr_un un;
struct path *path;
}

But even in this case we need to color this structure somehow (for 
example, set path to NULL for simple connect or bind call) . And to add 
this color, we have to separate sys_connect () from our 
sock->ops->connect() call. And I don't really know how to do it since we 
don't have any info about socket type in sys_connect () in hands. I.e. 
we have it, but then we have to add some specific UNIX socket logic to 
completely generic sys_connect () and sys_bind () .



--b.


Signed-off-by: Stanislav Kinsbursky 
---
  include/net/af_unix.h |2 ++
  net/unix/af_unix.c|   25 ++---
  2 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/include/net/af_unix.h b/include/net/af_unix.h
index 2ee33da..559467e 100644
--- a/include/net/af_unix.h
+++ b/include/net/af_unix.h
@@ -67,6 +67,8 @@ struct unix_sock {
  
  long unix_inq_len(struct sock *sk);

  long unix_outq_len(struct sock *sk);
+int unix_stream_connect_root(struct path *root, struct socket *sock,
+struct sockaddr *uaddr, int addr_len, int flags);
  
  #ifdef CONFIG_SYSCTL

  extern int unix_sysctl_register(struct net *net);
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 641f2e4..a790ebc 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -759,7 +759,7 @@ out:mutex_unlock(>readlock);
return err;
  }
  
-static struct sock *unix_find_other(struct net *net,

+static struct sock *unix_find_other(struct net *net, struct path *root,
struct sockaddr_un *sunname, int len,
int type, unsigned int hash, int *error)
  {
@@ -769,7 +769,11 @@ static struct sock *unix_find_other(struct net *net,
  
  	if (sunname->sun_path[0]) {

struct inode *inode;
-   err = kern_path(sunname->sun_path, LOOKUP_FOLLOW, );
+
+   if (root)
+   err = vfs_path_lookup(root->dentry, root->mnt, 
sunname->sun_path, LOOKUP_FOLLOW, );
+   else
+   err = kern_path(sunname->sun_path, LOOKUP_FOLLOW, 
);
if (err)
goto fail;
inode = path.dentry->d_inode;
@@ -979,7 +983,7 @@ static int unix_dgram_connect(struct socket *sock, struct 
sockaddr *addr,
goto out;
  
  restart:

-   other = unix_find_other(net, sunaddr, alen, sock->type, hash, 
);
+   other = unix_find_other(net, NULL, sunaddr, alen, sock->type, hash, 
);
if (!other)
goto out;
  
@@ -1053,8 +1057,8 @@ static long unix_wait_for_peer(struct sock *other, long timeo)

return timeo;
  }
  
-static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr,

-  int addr_len, int flags)
+int unix_stream_connect_root(struct path *root, struct socket *sock,
+struct sockaddr *uaddr, int addr_len, int flags)
  {
struct sockaddr_un *sunaddr = (struct sockaddr_un *)uaddr;
struct sock *sk = sock->sk;
@@ -1098,7 +1102,7 @@ static int unix_stream_connect(struct socket *sock, 
struct sockaddr *uaddr,
  
  restart:

/*  Find listening sock. */
-   other = unix_find_other(net, sunaddr, addr_len, sk->sk_type, hash, 
);
+   other = unix_find_other(net, root, sunaddr, addr_len, sk->sk_type, hash, 
);
if (!other)
goto out;
  
@@ -1227,6 +1231,13 @@ out:

sock_put(other);
return err;
  }
+EXPORT_SYMBOL_GPL(unix_stream_connect_root);
+
+static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr,
+   int addr_len, int 

Re: [RFC PATCH 1/2] unix sockets: add ability for search for peer from passed root

2012-08-10 Thread J. Bruce Fields
On Fri, Aug 10, 2012 at 04:57:30PM +0400, Stanislav Kinsbursky wrote:
> This helper is used stream sockets yet.
> All is simple: if non-NULL struct path was passed to unix_find_other(), then
> vfs_path_lookup() is called instead of kern_path().

I'm having some trouble parsing the changelog.  Maybe something like?:

unix sockets: add ability to look up using passed-in root

Export a unix_stream_connect_root() helper that allows a caller
to optionally pass in a root path, in which case the lookup will
be done relative to the given path instead of the current
working directory.

I guess this is a question for the networking people, but: will it cause
problems to have sunrpc calling directly into the unix socket code?

(And if so, what would be the alternative: define some variant of
sockaddr_un that includes the root path?  Something better?)

--b.

> 
> Signed-off-by: Stanislav Kinsbursky 
> ---
>  include/net/af_unix.h |2 ++
>  net/unix/af_unix.c|   25 ++---
>  2 files changed, 20 insertions(+), 7 deletions(-)
> 
> diff --git a/include/net/af_unix.h b/include/net/af_unix.h
> index 2ee33da..559467e 100644
> --- a/include/net/af_unix.h
> +++ b/include/net/af_unix.h
> @@ -67,6 +67,8 @@ struct unix_sock {
>  
>  long unix_inq_len(struct sock *sk);
>  long unix_outq_len(struct sock *sk);
> +int unix_stream_connect_root(struct path *root, struct socket *sock,
> +  struct sockaddr *uaddr, int addr_len, int flags);
>  
>  #ifdef CONFIG_SYSCTL
>  extern int unix_sysctl_register(struct net *net);
> diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
> index 641f2e4..a790ebc 100644
> --- a/net/unix/af_unix.c
> +++ b/net/unix/af_unix.c
> @@ -759,7 +759,7 @@ out:  mutex_unlock(>readlock);
>   return err;
>  }
>  
> -static struct sock *unix_find_other(struct net *net,
> +static struct sock *unix_find_other(struct net *net, struct path *root,
>   struct sockaddr_un *sunname, int len,
>   int type, unsigned int hash, int *error)
>  {
> @@ -769,7 +769,11 @@ static struct sock *unix_find_other(struct net *net,
>  
>   if (sunname->sun_path[0]) {
>   struct inode *inode;
> - err = kern_path(sunname->sun_path, LOOKUP_FOLLOW, );
> +
> + if (root)
> + err = vfs_path_lookup(root->dentry, root->mnt, 
> sunname->sun_path, LOOKUP_FOLLOW, );
> + else
> + err = kern_path(sunname->sun_path, LOOKUP_FOLLOW, 
> );
>   if (err)
>   goto fail;
>   inode = path.dentry->d_inode;
> @@ -979,7 +983,7 @@ static int unix_dgram_connect(struct socket *sock, struct 
> sockaddr *addr,
>   goto out;
>  
>  restart:
> - other = unix_find_other(net, sunaddr, alen, sock->type, hash, 
> );
> + other = unix_find_other(net, NULL, sunaddr, alen, sock->type, 
> hash, );
>   if (!other)
>   goto out;
>  
> @@ -1053,8 +1057,8 @@ static long unix_wait_for_peer(struct sock *other, long 
> timeo)
>   return timeo;
>  }
>  
> -static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr,
> -int addr_len, int flags)
> +int unix_stream_connect_root(struct path *root, struct socket *sock,
> +  struct sockaddr *uaddr, int addr_len, int flags)
>  {
>   struct sockaddr_un *sunaddr = (struct sockaddr_un *)uaddr;
>   struct sock *sk = sock->sk;
> @@ -1098,7 +1102,7 @@ static int unix_stream_connect(struct socket *sock, 
> struct sockaddr *uaddr,
>  
>  restart:
>   /*  Find listening sock. */
> - other = unix_find_other(net, sunaddr, addr_len, sk->sk_type, hash, 
> );
> + other = unix_find_other(net, root, sunaddr, addr_len, sk->sk_type, 
> hash, );
>   if (!other)
>   goto out;
>  
> @@ -1227,6 +1231,13 @@ out:
>   sock_put(other);
>   return err;
>  }
> +EXPORT_SYMBOL_GPL(unix_stream_connect_root);
> +
> +static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr,
> + int addr_len, int flags)
> +{
> + return unix_stream_connect_root(NULL, sock, uaddr, addr_len, flags);
> +}
>  
>  static int unix_socketpair(struct socket *socka, struct socket *sockb)
>  {
> @@ -1508,7 +1519,7 @@ restart:
>   if (sunaddr == NULL)
>   goto out_free;
>  
> - other = unix_find_other(net, sunaddr, namelen, sk->sk_type,
> + other = unix_find_other(net, NULL, sunaddr, namelen, 
> sk->sk_type,
>   hash, );
>   if (other == NULL)
>   goto out_free;
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
> the body of a message to majord...@vger.kernel.org
> More majordomo info at  

[RFC PATCH 1/2] unix sockets: add ability for search for peer from passed root

2012-08-10 Thread Stanislav Kinsbursky
This helper is used stream sockets yet.
All is simple: if non-NULL struct path was passed to unix_find_other(), then
vfs_path_lookup() is called instead of kern_path().

Signed-off-by: Stanislav Kinsbursky 
---
 include/net/af_unix.h |2 ++
 net/unix/af_unix.c|   25 ++---
 2 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/include/net/af_unix.h b/include/net/af_unix.h
index 2ee33da..559467e 100644
--- a/include/net/af_unix.h
+++ b/include/net/af_unix.h
@@ -67,6 +67,8 @@ struct unix_sock {
 
 long unix_inq_len(struct sock *sk);
 long unix_outq_len(struct sock *sk);
+int unix_stream_connect_root(struct path *root, struct socket *sock,
+struct sockaddr *uaddr, int addr_len, int flags);
 
 #ifdef CONFIG_SYSCTL
 extern int unix_sysctl_register(struct net *net);
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 641f2e4..a790ebc 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -759,7 +759,7 @@ out:mutex_unlock(>readlock);
return err;
 }
 
-static struct sock *unix_find_other(struct net *net,
+static struct sock *unix_find_other(struct net *net, struct path *root,
struct sockaddr_un *sunname, int len,
int type, unsigned int hash, int *error)
 {
@@ -769,7 +769,11 @@ static struct sock *unix_find_other(struct net *net,
 
if (sunname->sun_path[0]) {
struct inode *inode;
-   err = kern_path(sunname->sun_path, LOOKUP_FOLLOW, );
+
+   if (root)
+   err = vfs_path_lookup(root->dentry, root->mnt, 
sunname->sun_path, LOOKUP_FOLLOW, );
+   else
+   err = kern_path(sunname->sun_path, LOOKUP_FOLLOW, 
);
if (err)
goto fail;
inode = path.dentry->d_inode;
@@ -979,7 +983,7 @@ static int unix_dgram_connect(struct socket *sock, struct 
sockaddr *addr,
goto out;
 
 restart:
-   other = unix_find_other(net, sunaddr, alen, sock->type, hash, 
);
+   other = unix_find_other(net, NULL, sunaddr, alen, sock->type, 
hash, );
if (!other)
goto out;
 
@@ -1053,8 +1057,8 @@ static long unix_wait_for_peer(struct sock *other, long 
timeo)
return timeo;
 }
 
-static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr,
-  int addr_len, int flags)
+int unix_stream_connect_root(struct path *root, struct socket *sock,
+struct sockaddr *uaddr, int addr_len, int flags)
 {
struct sockaddr_un *sunaddr = (struct sockaddr_un *)uaddr;
struct sock *sk = sock->sk;
@@ -1098,7 +1102,7 @@ static int unix_stream_connect(struct socket *sock, 
struct sockaddr *uaddr,
 
 restart:
/*  Find listening sock. */
-   other = unix_find_other(net, sunaddr, addr_len, sk->sk_type, hash, 
);
+   other = unix_find_other(net, root, sunaddr, addr_len, sk->sk_type, 
hash, );
if (!other)
goto out;
 
@@ -1227,6 +1231,13 @@ out:
sock_put(other);
return err;
 }
+EXPORT_SYMBOL_GPL(unix_stream_connect_root);
+
+static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr,
+   int addr_len, int flags)
+{
+   return unix_stream_connect_root(NULL, sock, uaddr, addr_len, flags);
+}
 
 static int unix_socketpair(struct socket *socka, struct socket *sockb)
 {
@@ -1508,7 +1519,7 @@ restart:
if (sunaddr == NULL)
goto out_free;
 
-   other = unix_find_other(net, sunaddr, namelen, sk->sk_type,
+   other = unix_find_other(net, NULL, sunaddr, namelen, 
sk->sk_type,
hash, );
if (other == NULL)
goto out_free;

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Please read the FAQ at  http://www.tux.org/lkml/


[RFC PATCH 1/2] unix sockets: add ability for search for peer from passed root

2012-08-10 Thread Stanislav Kinsbursky
This helper is used stream sockets yet.
All is simple: if non-NULL struct path was passed to unix_find_other(), then
vfs_path_lookup() is called instead of kern_path().

Signed-off-by: Stanislav Kinsbursky skinsbur...@parallels.com
---
 include/net/af_unix.h |2 ++
 net/unix/af_unix.c|   25 ++---
 2 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/include/net/af_unix.h b/include/net/af_unix.h
index 2ee33da..559467e 100644
--- a/include/net/af_unix.h
+++ b/include/net/af_unix.h
@@ -67,6 +67,8 @@ struct unix_sock {
 
 long unix_inq_len(struct sock *sk);
 long unix_outq_len(struct sock *sk);
+int unix_stream_connect_root(struct path *root, struct socket *sock,
+struct sockaddr *uaddr, int addr_len, int flags);
 
 #ifdef CONFIG_SYSCTL
 extern int unix_sysctl_register(struct net *net);
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 641f2e4..a790ebc 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -759,7 +759,7 @@ out:mutex_unlock(u-readlock);
return err;
 }
 
-static struct sock *unix_find_other(struct net *net,
+static struct sock *unix_find_other(struct net *net, struct path *root,
struct sockaddr_un *sunname, int len,
int type, unsigned int hash, int *error)
 {
@@ -769,7 +769,11 @@ static struct sock *unix_find_other(struct net *net,
 
if (sunname-sun_path[0]) {
struct inode *inode;
-   err = kern_path(sunname-sun_path, LOOKUP_FOLLOW, path);
+
+   if (root)
+   err = vfs_path_lookup(root-dentry, root-mnt, 
sunname-sun_path, LOOKUP_FOLLOW, path);
+   else
+   err = kern_path(sunname-sun_path, LOOKUP_FOLLOW, 
path);
if (err)
goto fail;
inode = path.dentry-d_inode;
@@ -979,7 +983,7 @@ static int unix_dgram_connect(struct socket *sock, struct 
sockaddr *addr,
goto out;
 
 restart:
-   other = unix_find_other(net, sunaddr, alen, sock-type, hash, 
err);
+   other = unix_find_other(net, NULL, sunaddr, alen, sock-type, 
hash, err);
if (!other)
goto out;
 
@@ -1053,8 +1057,8 @@ static long unix_wait_for_peer(struct sock *other, long 
timeo)
return timeo;
 }
 
-static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr,
-  int addr_len, int flags)
+int unix_stream_connect_root(struct path *root, struct socket *sock,
+struct sockaddr *uaddr, int addr_len, int flags)
 {
struct sockaddr_un *sunaddr = (struct sockaddr_un *)uaddr;
struct sock *sk = sock-sk;
@@ -1098,7 +1102,7 @@ static int unix_stream_connect(struct socket *sock, 
struct sockaddr *uaddr,
 
 restart:
/*  Find listening sock. */
-   other = unix_find_other(net, sunaddr, addr_len, sk-sk_type, hash, 
err);
+   other = unix_find_other(net, root, sunaddr, addr_len, sk-sk_type, 
hash, err);
if (!other)
goto out;
 
@@ -1227,6 +1231,13 @@ out:
sock_put(other);
return err;
 }
+EXPORT_SYMBOL_GPL(unix_stream_connect_root);
+
+static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr,
+   int addr_len, int flags)
+{
+   return unix_stream_connect_root(NULL, sock, uaddr, addr_len, flags);
+}
 
 static int unix_socketpair(struct socket *socka, struct socket *sockb)
 {
@@ -1508,7 +1519,7 @@ restart:
if (sunaddr == NULL)
goto out_free;
 
-   other = unix_find_other(net, sunaddr, namelen, sk-sk_type,
+   other = unix_find_other(net, NULL, sunaddr, namelen, 
sk-sk_type,
hash, err);
if (other == NULL)
goto out_free;

--
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Please read the FAQ at  http://www.tux.org/lkml/


Re: [RFC PATCH 1/2] unix sockets: add ability for search for peer from passed root

2012-08-10 Thread J. Bruce Fields
On Fri, Aug 10, 2012 at 04:57:30PM +0400, Stanislav Kinsbursky wrote:
 This helper is used stream sockets yet.
 All is simple: if non-NULL struct path was passed to unix_find_other(), then
 vfs_path_lookup() is called instead of kern_path().

I'm having some trouble parsing the changelog.  Maybe something like?:

unix sockets: add ability to look up using passed-in root

Export a unix_stream_connect_root() helper that allows a caller
to optionally pass in a root path, in which case the lookup will
be done relative to the given path instead of the current
working directory.

I guess this is a question for the networking people, but: will it cause
problems to have sunrpc calling directly into the unix socket code?

(And if so, what would be the alternative: define some variant of
sockaddr_un that includes the root path?  Something better?)

--b.

 
 Signed-off-by: Stanislav Kinsbursky skinsbur...@parallels.com
 ---
  include/net/af_unix.h |2 ++
  net/unix/af_unix.c|   25 ++---
  2 files changed, 20 insertions(+), 7 deletions(-)
 
 diff --git a/include/net/af_unix.h b/include/net/af_unix.h
 index 2ee33da..559467e 100644
 --- a/include/net/af_unix.h
 +++ b/include/net/af_unix.h
 @@ -67,6 +67,8 @@ struct unix_sock {
  
  long unix_inq_len(struct sock *sk);
  long unix_outq_len(struct sock *sk);
 +int unix_stream_connect_root(struct path *root, struct socket *sock,
 +  struct sockaddr *uaddr, int addr_len, int flags);
  
  #ifdef CONFIG_SYSCTL
  extern int unix_sysctl_register(struct net *net);
 diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
 index 641f2e4..a790ebc 100644
 --- a/net/unix/af_unix.c
 +++ b/net/unix/af_unix.c
 @@ -759,7 +759,7 @@ out:  mutex_unlock(u-readlock);
   return err;
  }
  
 -static struct sock *unix_find_other(struct net *net,
 +static struct sock *unix_find_other(struct net *net, struct path *root,
   struct sockaddr_un *sunname, int len,
   int type, unsigned int hash, int *error)
  {
 @@ -769,7 +769,11 @@ static struct sock *unix_find_other(struct net *net,
  
   if (sunname-sun_path[0]) {
   struct inode *inode;
 - err = kern_path(sunname-sun_path, LOOKUP_FOLLOW, path);
 +
 + if (root)
 + err = vfs_path_lookup(root-dentry, root-mnt, 
 sunname-sun_path, LOOKUP_FOLLOW, path);
 + else
 + err = kern_path(sunname-sun_path, LOOKUP_FOLLOW, 
 path);
   if (err)
   goto fail;
   inode = path.dentry-d_inode;
 @@ -979,7 +983,7 @@ static int unix_dgram_connect(struct socket *sock, struct 
 sockaddr *addr,
   goto out;
  
  restart:
 - other = unix_find_other(net, sunaddr, alen, sock-type, hash, 
 err);
 + other = unix_find_other(net, NULL, sunaddr, alen, sock-type, 
 hash, err);
   if (!other)
   goto out;
  
 @@ -1053,8 +1057,8 @@ static long unix_wait_for_peer(struct sock *other, long 
 timeo)
   return timeo;
  }
  
 -static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr,
 -int addr_len, int flags)
 +int unix_stream_connect_root(struct path *root, struct socket *sock,
 +  struct sockaddr *uaddr, int addr_len, int flags)
  {
   struct sockaddr_un *sunaddr = (struct sockaddr_un *)uaddr;
   struct sock *sk = sock-sk;
 @@ -1098,7 +1102,7 @@ static int unix_stream_connect(struct socket *sock, 
 struct sockaddr *uaddr,
  
  restart:
   /*  Find listening sock. */
 - other = unix_find_other(net, sunaddr, addr_len, sk-sk_type, hash, 
 err);
 + other = unix_find_other(net, root, sunaddr, addr_len, sk-sk_type, 
 hash, err);
   if (!other)
   goto out;
  
 @@ -1227,6 +1231,13 @@ out:
   sock_put(other);
   return err;
  }
 +EXPORT_SYMBOL_GPL(unix_stream_connect_root);
 +
 +static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr,
 + int addr_len, int flags)
 +{
 + return unix_stream_connect_root(NULL, sock, uaddr, addr_len, flags);
 +}
  
  static int unix_socketpair(struct socket *socka, struct socket *sockb)
  {
 @@ -1508,7 +1519,7 @@ restart:
   if (sunaddr == NULL)
   goto out_free;
  
 - other = unix_find_other(net, sunaddr, namelen, sk-sk_type,
 + other = unix_find_other(net, NULL, sunaddr, namelen, 
 sk-sk_type,
   hash, err);
   if (other == NULL)
   goto out_free;
 
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Re: [RFC PATCH 1/2] unix sockets: add ability for search for peer from passed root

2012-08-10 Thread Stanislav Kinsbursky

10.08.2012 22:10, J. Bruce Fields пишет:

On Fri, Aug 10, 2012 at 04:57:30PM +0400, Stanislav Kinsbursky wrote:

This helper is used stream sockets yet.
All is simple: if non-NULL struct path was passed to unix_find_other(), then
vfs_path_lookup() is called instead of kern_path().

I'm having some trouble parsing the changelog.  Maybe something like?:

unix sockets: add ability to look up using passed-in root

Export a unix_stream_connect_root() helper that allows a caller
to optionally pass in a root path, in which case the lookup will
be done relative to the given path instead of the current
working directory.


Yep, your variant is much better. Thanks.



I guess this is a question for the networking people, but: will it cause
problems to have sunrpc calling directly into the unix socket code?

(And if so, what would be the alternative: define some variant of
sockaddr_un that includes the root path?  Something better?)


That was my first idea. But there are problems with this solution (add 
root path to sockaddr_un) :
1) sockaddr_un size will change. I don't know, how this will affect 
user-space. Of course, we can introduce something like:


struct sockaddr_un_kern {
struct sockaddr_un un;
struct path *path;
}

But even in this case we need to color this structure somehow (for 
example, set path to NULL for simple connect or bind call) . And to add 
this color, we have to separate sys_connect () from our 
sock-ops-connect() call. And I don't really know how to do it since we 
don't have any info about socket type in sys_connect () in hands. I.e. 
we have it, but then we have to add some specific UNIX socket logic to 
completely generic sys_connect () and sys_bind () .



--b.


Signed-off-by: Stanislav Kinsbursky skinsbur...@parallels.com
---
  include/net/af_unix.h |2 ++
  net/unix/af_unix.c|   25 ++---
  2 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/include/net/af_unix.h b/include/net/af_unix.h
index 2ee33da..559467e 100644
--- a/include/net/af_unix.h
+++ b/include/net/af_unix.h
@@ -67,6 +67,8 @@ struct unix_sock {
  
  long unix_inq_len(struct sock *sk);

  long unix_outq_len(struct sock *sk);
+int unix_stream_connect_root(struct path *root, struct socket *sock,
+struct sockaddr *uaddr, int addr_len, int flags);
  
  #ifdef CONFIG_SYSCTL

  extern int unix_sysctl_register(struct net *net);
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 641f2e4..a790ebc 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -759,7 +759,7 @@ out:mutex_unlock(u-readlock);
return err;
  }
  
-static struct sock *unix_find_other(struct net *net,

+static struct sock *unix_find_other(struct net *net, struct path *root,
struct sockaddr_un *sunname, int len,
int type, unsigned int hash, int *error)
  {
@@ -769,7 +769,11 @@ static struct sock *unix_find_other(struct net *net,
  
  	if (sunname-sun_path[0]) {

struct inode *inode;
-   err = kern_path(sunname-sun_path, LOOKUP_FOLLOW, path);
+
+   if (root)
+   err = vfs_path_lookup(root-dentry, root-mnt, 
sunname-sun_path, LOOKUP_FOLLOW, path);
+   else
+   err = kern_path(sunname-sun_path, LOOKUP_FOLLOW, 
path);
if (err)
goto fail;
inode = path.dentry-d_inode;
@@ -979,7 +983,7 @@ static int unix_dgram_connect(struct socket *sock, struct 
sockaddr *addr,
goto out;
  
  restart:

-   other = unix_find_other(net, sunaddr, alen, sock-type, hash, 
err);
+   other = unix_find_other(net, NULL, sunaddr, alen, sock-type, hash, 
err);
if (!other)
goto out;
  
@@ -1053,8 +1057,8 @@ static long unix_wait_for_peer(struct sock *other, long timeo)

return timeo;
  }
  
-static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr,

-  int addr_len, int flags)
+int unix_stream_connect_root(struct path *root, struct socket *sock,
+struct sockaddr *uaddr, int addr_len, int flags)
  {
struct sockaddr_un *sunaddr = (struct sockaddr_un *)uaddr;
struct sock *sk = sock-sk;
@@ -1098,7 +1102,7 @@ static int unix_stream_connect(struct socket *sock, 
struct sockaddr *uaddr,
  
  restart:

/*  Find listening sock. */
-   other = unix_find_other(net, sunaddr, addr_len, sk-sk_type, hash, 
err);
+   other = unix_find_other(net, root, sunaddr, addr_len, sk-sk_type, hash, 
err);
if (!other)
goto out;
  
@@ -1227,6 +1231,13 @@ out:

sock_put(other);
return err;
  }
+EXPORT_SYMBOL_GPL(unix_stream_connect_root);
+
+static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr,
+