* [PATCH 2/8] unix_bind(): allocate addr earlier
2021-02-22 19:12 ` [PATCH 1/8] af_unix: take address assignment/hash insertion into a new helper Al Viro
@ 2021-02-22 19:12 ` Al Viro
2021-02-22 19:12 ` [PATCH 3/8] unix_bind(): separate BSD and abstract cases Al Viro
` (5 subsequent siblings)
6 siblings, 0 replies; 12+ messages in thread
From: Al Viro @ 2021-02-22 19:12 UTC (permalink / raw)
To: netdev
Cc: linux-kernel, Christoph Hellwig, Jakub Kicinski, Denis Kirjanov,
linux-fsdevel, Cong Wang
makes it easier to massage; we do pay for that by extra work
(kmalloc+memcpy+kfree) in some error cases, but those are not
on the hot paths anyway.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
net/unix/af_unix.c | 28 +++++++++++++++-------------
1 file changed, 15 insertions(+), 13 deletions(-)
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 45a40cf7b6af..54f1bfe14191 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -1038,6 +1038,15 @@ static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
if (err < 0)
goto out;
addr_len = err;
+ err = -ENOMEM;
+ addr = kmalloc(sizeof(*addr)+addr_len, GFP_KERNEL);
+ if (!addr)
+ goto out;
+
+ memcpy(addr->name, sunaddr, addr_len);
+ addr->len = addr_len;
+ addr->hash = hash ^ sk->sk_type;
+ refcount_set(&addr->refcnt, 1);
if (sun_path[0]) {
umode_t mode = S_IFSOCK |
@@ -1046,7 +1055,7 @@ static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
if (err) {
if (err == -EEXIST)
err = -EADDRINUSE;
- goto out;
+ goto out_addr;
}
}
@@ -1058,16 +1067,6 @@ static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
if (u->addr)
goto out_up;
- err = -ENOMEM;
- addr = kmalloc(sizeof(*addr)+addr_len, GFP_KERNEL);
- if (!addr)
- goto out_up;
-
- memcpy(addr->name, sunaddr, addr_len);
- addr->len = addr_len;
- addr->hash = hash ^ sk->sk_type;
- refcount_set(&addr->refcnt, 1);
-
if (sun_path[0]) {
addr->hash = UNIX_HASH_SIZE;
hash = d_backing_inode(path.dentry)->i_ino & (UNIX_HASH_SIZE - 1);
@@ -1079,20 +1078,23 @@ static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
if (__unix_find_socket_byname(net, sunaddr, addr_len,
sk->sk_type, hash)) {
spin_unlock(&unix_table_lock);
- unix_release_addr(addr);
goto out_up;
}
hash = addr->hash;
}
- err = 0;
__unix_set_addr(sk, addr, hash);
spin_unlock(&unix_table_lock);
+ addr = NULL;
+ err = 0;
out_up:
mutex_unlock(&u->bindlock);
out_put:
if (err)
path_put(&path);
+out_addr:
+ if (addr)
+ unix_release_addr(addr);
out:
return err;
}
--
2.11.0
^ permalink raw reply related [flat|nested] 12+ messages in thread* [PATCH 3/8] unix_bind(): separate BSD and abstract cases
2021-02-22 19:12 ` [PATCH 1/8] af_unix: take address assignment/hash insertion into a new helper Al Viro
2021-02-22 19:12 ` [PATCH 2/8] unix_bind(): allocate addr earlier Al Viro
@ 2021-02-22 19:12 ` Al Viro
2021-02-22 19:12 ` [PATCH 4/8] unix_bind(): take BSD and abstract address cases into new helpers Al Viro
` (4 subsequent siblings)
6 siblings, 0 replies; 12+ messages in thread
From: Al Viro @ 2021-02-22 19:12 UTC (permalink / raw)
To: netdev
Cc: linux-kernel, Christoph Hellwig, Jakub Kicinski, Denis Kirjanov,
linux-fsdevel, Cong Wang
We do get some duplication that way, but it's minor compared to
parts that are different. What we get is an ability to change
locking in BSD case without making failure exits very hard to
follow.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
net/unix/af_unix.c | 55 +++++++++++++++++++++++++++++++++---------------------
1 file changed, 34 insertions(+), 21 deletions(-)
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 54f1bfe14191..496b069c99fe 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -1022,7 +1022,6 @@ static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
int err;
unsigned int hash;
struct unix_address *addr;
- struct path path = { };
err = -EINVAL;
if (addr_len < offsetofend(struct sockaddr_un, sun_family) ||
@@ -1049,6 +1048,7 @@ static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
refcount_set(&addr->refcnt, 1);
if (sun_path[0]) {
+ struct path path = { };
umode_t mode = S_IFSOCK |
(SOCK_INODE(sock)->i_mode & ~current_umask());
err = unix_mknod(sun_path, mode, &path);
@@ -1057,41 +1057,54 @@ static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
err = -EADDRINUSE;
goto out_addr;
}
- }
- err = mutex_lock_interruptible(&u->bindlock);
- if (err)
- goto out_put;
+ err = mutex_lock_interruptible(&u->bindlock);
+ if (err) {
+ path_put(&path);
+ goto out_addr;
+ }
- err = -EINVAL;
- if (u->addr)
- goto out_up;
+ err = -EINVAL;
+ if (u->addr) {
+ mutex_unlock(&u->bindlock);
+ path_put(&path);
+ goto out_addr;
+ }
- if (sun_path[0]) {
addr->hash = UNIX_HASH_SIZE;
hash = d_backing_inode(path.dentry)->i_ino & (UNIX_HASH_SIZE - 1);
spin_lock(&unix_table_lock);
u->path = path;
+ __unix_set_addr(sk, addr, hash);
+ spin_unlock(&unix_table_lock);
+ mutex_unlock(&u->bindlock);
+ addr = NULL;
+ err = 0;
} else {
+ err = mutex_lock_interruptible(&u->bindlock);
+ if (err)
+ goto out_addr;
+
+ err = -EINVAL;
+ if (u->addr) {
+ mutex_unlock(&u->bindlock);
+ goto out_addr;
+ }
+
spin_lock(&unix_table_lock);
err = -EADDRINUSE;
if (__unix_find_socket_byname(net, sunaddr, addr_len,
sk->sk_type, hash)) {
spin_unlock(&unix_table_lock);
- goto out_up;
+ mutex_unlock(&u->bindlock);
+ goto out_addr;
}
- hash = addr->hash;
+ __unix_set_addr(sk, addr, addr->hash);
+ spin_unlock(&unix_table_lock);
+ mutex_unlock(&u->bindlock);
+ addr = NULL;
+ err = 0;
}
-
- __unix_set_addr(sk, addr, hash);
- spin_unlock(&unix_table_lock);
- addr = NULL;
- err = 0;
-out_up:
- mutex_unlock(&u->bindlock);
-out_put:
- if (err)
- path_put(&path);
out_addr:
if (addr)
unix_release_addr(addr);
--
2.11.0
^ permalink raw reply related [flat|nested] 12+ messages in thread* [PATCH 4/8] unix_bind(): take BSD and abstract address cases into new helpers
2021-02-22 19:12 ` [PATCH 1/8] af_unix: take address assignment/hash insertion into a new helper Al Viro
2021-02-22 19:12 ` [PATCH 2/8] unix_bind(): allocate addr earlier Al Viro
2021-02-22 19:12 ` [PATCH 3/8] unix_bind(): separate BSD and abstract cases Al Viro
@ 2021-02-22 19:12 ` Al Viro
2021-02-22 19:12 ` [PATCH 5/8] fold unix_mknod() into unix_bind_bsd() Al Viro
` (3 subsequent siblings)
6 siblings, 0 replies; 12+ messages in thread
From: Al Viro @ 2021-02-22 19:12 UTC (permalink / raw)
To: netdev
Cc: linux-kernel, Christoph Hellwig, Jakub Kicinski, Denis Kirjanov,
linux-fsdevel, Cong Wang
unix_bind_bsd() and unix_bind_abstract() respectively.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
net/unix/af_unix.c | 147 +++++++++++++++++++++++++++--------------------------
1 file changed, 74 insertions(+), 73 deletions(-)
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 496b069c99fe..56443f05ed9d 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -1012,104 +1012,105 @@ static int unix_mknod(const char *sun_path, umode_t mode, struct path *res)
return err;
}
+static int unix_bind_bsd(struct sock *sk, struct unix_address *addr)
+{
+ struct unix_sock *u = unix_sk(sk);
+ struct path path = { };
+ umode_t mode = S_IFSOCK |
+ (SOCK_INODE(sk->sk_socket)->i_mode & ~current_umask());
+ unsigned int hash;
+ int err;
+
+ err = unix_mknod(addr->name->sun_path, mode, &path);
+ if (err)
+ return err;
+
+ err = mutex_lock_interruptible(&u->bindlock);
+ if (err) {
+ path_put(&path);
+ return err;
+ }
+
+ if (u->addr) {
+ mutex_unlock(&u->bindlock);
+ path_put(&path);
+ return -EINVAL;
+ }
+
+ addr->hash = UNIX_HASH_SIZE;
+ hash = d_backing_inode(path.dentry)->i_ino & (UNIX_HASH_SIZE - 1);
+ spin_lock(&unix_table_lock);
+ u->path = path;
+ __unix_set_addr(sk, addr, hash);
+ spin_unlock(&unix_table_lock);
+ mutex_unlock(&u->bindlock);
+ return 0;
+}
+
+static int unix_bind_abstract(struct sock *sk, unsigned hash,
+ struct unix_address *addr)
+{
+ struct unix_sock *u = unix_sk(sk);
+ int err;
+
+ err = mutex_lock_interruptible(&u->bindlock);
+ if (err)
+ return err;
+
+ if (u->addr) {
+ mutex_unlock(&u->bindlock);
+ return -EINVAL;
+ }
+
+ spin_lock(&unix_table_lock);
+ if (__unix_find_socket_byname(sock_net(sk), addr->name, addr->len,
+ sk->sk_type, hash)) {
+ spin_unlock(&unix_table_lock);
+ mutex_unlock(&u->bindlock);
+ return -EADDRINUSE;
+ }
+ __unix_set_addr(sk, addr, addr->hash);
+ spin_unlock(&unix_table_lock);
+ mutex_unlock(&u->bindlock);
+ return 0;
+}
+
static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
{
struct sock *sk = sock->sk;
- struct net *net = sock_net(sk);
- struct unix_sock *u = unix_sk(sk);
struct sockaddr_un *sunaddr = (struct sockaddr_un *)uaddr;
char *sun_path = sunaddr->sun_path;
int err;
unsigned int hash;
struct unix_address *addr;
- err = -EINVAL;
if (addr_len < offsetofend(struct sockaddr_un, sun_family) ||
sunaddr->sun_family != AF_UNIX)
- goto out;
+ return -EINVAL;
- if (addr_len == sizeof(short)) {
- err = unix_autobind(sock);
- goto out;
- }
+ if (addr_len == sizeof(short))
+ return unix_autobind(sock);
err = unix_mkname(sunaddr, addr_len, &hash);
if (err < 0)
- goto out;
+ return err;
addr_len = err;
- err = -ENOMEM;
addr = kmalloc(sizeof(*addr)+addr_len, GFP_KERNEL);
if (!addr)
- goto out;
+ return -ENOMEM;
memcpy(addr->name, sunaddr, addr_len);
addr->len = addr_len;
addr->hash = hash ^ sk->sk_type;
refcount_set(&addr->refcnt, 1);
- if (sun_path[0]) {
- struct path path = { };
- umode_t mode = S_IFSOCK |
- (SOCK_INODE(sock)->i_mode & ~current_umask());
- err = unix_mknod(sun_path, mode, &path);
- if (err) {
- if (err == -EEXIST)
- err = -EADDRINUSE;
- goto out_addr;
- }
-
- err = mutex_lock_interruptible(&u->bindlock);
- if (err) {
- path_put(&path);
- goto out_addr;
- }
-
- err = -EINVAL;
- if (u->addr) {
- mutex_unlock(&u->bindlock);
- path_put(&path);
- goto out_addr;
- }
-
- addr->hash = UNIX_HASH_SIZE;
- hash = d_backing_inode(path.dentry)->i_ino & (UNIX_HASH_SIZE - 1);
- spin_lock(&unix_table_lock);
- u->path = path;
- __unix_set_addr(sk, addr, hash);
- spin_unlock(&unix_table_lock);
- mutex_unlock(&u->bindlock);
- addr = NULL;
- err = 0;
- } else {
- err = mutex_lock_interruptible(&u->bindlock);
- if (err)
- goto out_addr;
-
- err = -EINVAL;
- if (u->addr) {
- mutex_unlock(&u->bindlock);
- goto out_addr;
- }
-
- spin_lock(&unix_table_lock);
- err = -EADDRINUSE;
- if (__unix_find_socket_byname(net, sunaddr, addr_len,
- sk->sk_type, hash)) {
- spin_unlock(&unix_table_lock);
- mutex_unlock(&u->bindlock);
- goto out_addr;
- }
- __unix_set_addr(sk, addr, addr->hash);
- spin_unlock(&unix_table_lock);
- mutex_unlock(&u->bindlock);
- addr = NULL;
- err = 0;
- }
-out_addr:
- if (addr)
+ if (sun_path[0])
+ err = unix_bind_bsd(sk, addr);
+ else
+ err = unix_bind_abstract(sk, hash, addr);
+ if (err)
unix_release_addr(addr);
-out:
- return err;
+ return err == -EEXIST ? -EADDRINUSE : err;
}
static void unix_state_double_lock(struct sock *sk1, struct sock *sk2)
--
2.11.0
^ permalink raw reply related [flat|nested] 12+ messages in thread* [PATCH 5/8] fold unix_mknod() into unix_bind_bsd()
2021-02-22 19:12 ` [PATCH 1/8] af_unix: take address assignment/hash insertion into a new helper Al Viro
` (2 preceding siblings ...)
2021-02-22 19:12 ` [PATCH 4/8] unix_bind(): take BSD and abstract address cases into new helpers Al Viro
@ 2021-02-22 19:12 ` Al Viro
2021-02-22 19:12 ` [PATCH 6/8] unix_bind_bsd(): move done_path_create() call after dealing with ->bindlock Al Viro
` (2 subsequent siblings)
6 siblings, 0 replies; 12+ messages in thread
From: Al Viro @ 2021-02-22 19:12 UTC (permalink / raw)
To: netdev
Cc: linux-kernel, Christoph Hellwig, Jakub Kicinski, Denis Kirjanov,
linux-fsdevel, Cong Wang
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
net/unix/af_unix.c | 39 +++++++++++++++------------------------
1 file changed, 15 insertions(+), 24 deletions(-)
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 56443f05ed9d..5e04e16e6b88 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -983,45 +983,36 @@ static struct sock *unix_find_other(struct net *net,
return NULL;
}
-static int unix_mknod(const char *sun_path, umode_t mode, struct path *res)
+static int unix_bind_bsd(struct sock *sk, struct unix_address *addr)
{
+ struct unix_sock *u = unix_sk(sk);
+ umode_t mode = S_IFSOCK |
+ (SOCK_INODE(sk->sk_socket)->i_mode & ~current_umask());
+ struct path parent, path;
struct dentry *dentry;
- struct path path;
- int err = 0;
+ unsigned int hash;
+ int err;
+
/*
* Get the parent directory, calculate the hash for last
* component.
*/
- dentry = kern_path_create(AT_FDCWD, sun_path, &path, 0);
- err = PTR_ERR(dentry);
+ dentry = kern_path_create(AT_FDCWD, addr->name->sun_path, &parent, 0);
if (IS_ERR(dentry))
- return err;
+ return PTR_ERR(dentry);
/*
* All right, let's create it.
*/
- err = security_path_mknod(&path, dentry, mode, 0);
+ err = security_path_mknod(&parent, dentry, mode, 0);
if (!err) {
- err = vfs_mknod(d_inode(path.dentry), dentry, mode, 0);
+ err = vfs_mknod(d_inode(parent.dentry), dentry, mode, 0);
if (!err) {
- res->mnt = mntget(path.mnt);
- res->dentry = dget(dentry);
+ path.mnt = mntget(parent.mnt);
+ path.dentry = dget(dentry);
}
}
- done_path_create(&path, dentry);
- return err;
-}
-
-static int unix_bind_bsd(struct sock *sk, struct unix_address *addr)
-{
- struct unix_sock *u = unix_sk(sk);
- struct path path = { };
- umode_t mode = S_IFSOCK |
- (SOCK_INODE(sk->sk_socket)->i_mode & ~current_umask());
- unsigned int hash;
- int err;
-
- err = unix_mknod(addr->name->sun_path, mode, &path);
+ done_path_create(&parent, dentry);
if (err)
return err;
--
2.11.0
^ permalink raw reply related [flat|nested] 12+ messages in thread* [PATCH 6/8] unix_bind_bsd(): move done_path_create() call after dealing with ->bindlock
2021-02-22 19:12 ` [PATCH 1/8] af_unix: take address assignment/hash insertion into a new helper Al Viro
` (3 preceding siblings ...)
2021-02-22 19:12 ` [PATCH 5/8] fold unix_mknod() into unix_bind_bsd() Al Viro
@ 2021-02-22 19:12 ` Al Viro
2021-02-22 19:12 ` [PATCH 7/8] unix_bind_bsd(): unlink if we fail after successful mknod Al Viro
2021-02-22 19:12 ` [PATCH 8/8] __unix_find_socket_byname(): don't pass hash and type separately Al Viro
6 siblings, 0 replies; 12+ messages in thread
From: Al Viro @ 2021-02-22 19:12 UTC (permalink / raw)
To: netdev
Cc: linux-kernel, Christoph Hellwig, Jakub Kicinski, Denis Kirjanov,
linux-fsdevel, Cong Wang
Final preparations for doing unlink on failure past the successful
mknod. We can't hold ->bindlock over ->mknod() or ->unlink(), since
either might do sb_start_write() (e.g. on overlayfs). However, we
can do it while holding filesystem and VFS locks - doing
kern_path_create()
vfs_mknod()
grab ->bindlock
if u->addr had been set
drop ->bindlock
done_path_create
return -EINVAL
else
assign the address to socket
drop ->bindlock
done_path_create
return 0
would be deadlock-free. Here we massage unix_bind_bsd() to that
form. We are still doing equivalent transformations.
Next commit will *not* be an equivalent transformation - it will
add a call of vfs_unlink() before done_path_create() in "alread bound"
case.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
net/unix/af_unix.c | 26 +++++++++++---------------
1 file changed, 11 insertions(+), 15 deletions(-)
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 5e04e16e6b88..368376621111 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -988,7 +988,7 @@ static int unix_bind_bsd(struct sock *sk, struct unix_address *addr)
struct unix_sock *u = unix_sk(sk);
umode_t mode = S_IFSOCK |
(SOCK_INODE(sk->sk_socket)->i_mode & ~current_umask());
- struct path parent, path;
+ struct path parent;
struct dentry *dentry;
unsigned int hash;
int err;
@@ -1005,36 +1005,32 @@ static int unix_bind_bsd(struct sock *sk, struct unix_address *addr)
* All right, let's create it.
*/
err = security_path_mknod(&parent, dentry, mode, 0);
- if (!err) {
+ if (!err)
err = vfs_mknod(d_inode(parent.dentry), dentry, mode, 0);
- if (!err) {
- path.mnt = mntget(parent.mnt);
- path.dentry = dget(dentry);
- }
- }
- done_path_create(&parent, dentry);
- if (err)
+ if (err) {
+ done_path_create(&parent, dentry);
return err;
-
+ }
err = mutex_lock_interruptible(&u->bindlock);
if (err) {
- path_put(&path);
+ done_path_create(&parent, dentry);
return err;
}
-
if (u->addr) {
mutex_unlock(&u->bindlock);
- path_put(&path);
+ done_path_create(&parent, dentry);
return -EINVAL;
}
addr->hash = UNIX_HASH_SIZE;
- hash = d_backing_inode(path.dentry)->i_ino & (UNIX_HASH_SIZE - 1);
+ hash = d_backing_inode(dentry)->i_ino & (UNIX_HASH_SIZE - 1);
spin_lock(&unix_table_lock);
- u->path = path;
+ u->path.mnt = mntget(parent.mnt);
+ u->path.dentry = dget(dentry);
__unix_set_addr(sk, addr, hash);
spin_unlock(&unix_table_lock);
mutex_unlock(&u->bindlock);
+ done_path_create(&parent, dentry);
return 0;
}
--
2.11.0
^ permalink raw reply related [flat|nested] 12+ messages in thread* [PATCH 7/8] unix_bind_bsd(): unlink if we fail after successful mknod
2021-02-22 19:12 ` [PATCH 1/8] af_unix: take address assignment/hash insertion into a new helper Al Viro
` (4 preceding siblings ...)
2021-02-22 19:12 ` [PATCH 6/8] unix_bind_bsd(): move done_path_create() call after dealing with ->bindlock Al Viro
@ 2021-02-22 19:12 ` Al Viro
2021-02-22 19:12 ` [PATCH 8/8] __unix_find_socket_byname(): don't pass hash and type separately Al Viro
6 siblings, 0 replies; 12+ messages in thread
From: Al Viro @ 2021-02-22 19:12 UTC (permalink / raw)
To: netdev
Cc: linux-kernel, Christoph Hellwig, Jakub Kicinski, Denis Kirjanov,
linux-fsdevel, Cong Wang
We can do that more or less safely, since the parent is
held locked all along. Yes, somebody might observe the
object via dcache, only to have it disappear afterwards,
but there's really no good way to prevent that. It won't
race with other bind(2) or attempts to move the sucker
elsewhere, or put something else in its place - locked
parent prevents that.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
net/unix/af_unix.c | 30 ++++++++++++++++--------------
1 file changed, 16 insertions(+), 14 deletions(-)
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 368376621111..8bbdcddbf598 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -1000,27 +1000,19 @@ static int unix_bind_bsd(struct sock *sk, struct unix_address *addr)
dentry = kern_path_create(AT_FDCWD, addr->name->sun_path, &parent, 0);
if (IS_ERR(dentry))
return PTR_ERR(dentry);
-
/*
* All right, let's create it.
*/
err = security_path_mknod(&parent, dentry, mode, 0);
if (!err)
err = vfs_mknod(d_inode(parent.dentry), dentry, mode, 0);
- if (err) {
- done_path_create(&parent, dentry);
- return err;
- }
+ if (err)
+ goto out;
err = mutex_lock_interruptible(&u->bindlock);
- if (err) {
- done_path_create(&parent, dentry);
- return err;
- }
- if (u->addr) {
- mutex_unlock(&u->bindlock);
- done_path_create(&parent, dentry);
- return -EINVAL;
- }
+ if (err)
+ goto out_unlink;
+ if (u->addr)
+ goto out_unlock;
addr->hash = UNIX_HASH_SIZE;
hash = d_backing_inode(dentry)->i_ino & (UNIX_HASH_SIZE - 1);
@@ -1032,6 +1024,16 @@ static int unix_bind_bsd(struct sock *sk, struct unix_address *addr)
mutex_unlock(&u->bindlock);
done_path_create(&parent, dentry);
return 0;
+
+out_unlock:
+ mutex_unlock(&u->bindlock);
+ err = -EINVAL;
+out_unlink:
+ /* failed after successful mknod? unlink what we'd created... */
+ vfs_unlink(d_inode(parent.dentry), dentry, NULL);
+out:
+ done_path_create(&parent, dentry);
+ return err;
}
static int unix_bind_abstract(struct sock *sk, unsigned hash,
--
2.11.0
^ permalink raw reply related [flat|nested] 12+ messages in thread* [PATCH 8/8] __unix_find_socket_byname(): don't pass hash and type separately
2021-02-22 19:12 ` [PATCH 1/8] af_unix: take address assignment/hash insertion into a new helper Al Viro
` (5 preceding siblings ...)
2021-02-22 19:12 ` [PATCH 7/8] unix_bind_bsd(): unlink if we fail after successful mknod Al Viro
@ 2021-02-22 19:12 ` Al Viro
6 siblings, 0 replies; 12+ messages in thread
From: Al Viro @ 2021-02-22 19:12 UTC (permalink / raw)
To: netdev
Cc: linux-kernel, Christoph Hellwig, Jakub Kicinski, Denis Kirjanov,
linux-fsdevel, Cong Wang
We only care about exclusive or of those, so pass that directly.
Makes life simpler for callers as well...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
net/unix/af_unix.c | 23 ++++++++++-------------
1 file changed, 10 insertions(+), 13 deletions(-)
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 8bbdcddbf598..3c1218be7165 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -286,11 +286,11 @@ static inline void unix_insert_socket(struct hlist_head *list, struct sock *sk)
static struct sock *__unix_find_socket_byname(struct net *net,
struct sockaddr_un *sunname,
- int len, int type, unsigned int hash)
+ int len, unsigned int hash)
{
struct sock *s;
- sk_for_each(s, &unix_socket_table[hash ^ type]) {
+ sk_for_each(s, &unix_socket_table[hash]) {
struct unix_sock *u = unix_sk(s);
if (!net_eq(sock_net(s), net))
@@ -305,13 +305,12 @@ static struct sock *__unix_find_socket_byname(struct net *net,
static inline struct sock *unix_find_socket_byname(struct net *net,
struct sockaddr_un *sunname,
- int len, int type,
- unsigned int hash)
+ int len, unsigned int hash)
{
struct sock *s;
spin_lock(&unix_table_lock);
- s = __unix_find_socket_byname(net, sunname, len, type, hash);
+ s = __unix_find_socket_byname(net, sunname, len, hash);
if (s)
sock_hold(s);
spin_unlock(&unix_table_lock);
@@ -898,12 +897,12 @@ static int unix_autobind(struct socket *sock)
retry:
addr->len = sprintf(addr->name->sun_path+1, "%05x", ordernum) + 1 + sizeof(short);
addr->hash = unix_hash_fold(csum_partial(addr->name, addr->len, 0));
+ addr->hash ^= sk->sk_type;
spin_lock(&unix_table_lock);
ordernum = (ordernum+1)&0xFFFFF;
- if (__unix_find_socket_byname(net, addr->name, addr->len, sock->type,
- addr->hash)) {
+ if (__unix_find_socket_byname(net, addr->name, addr->len, addr->hash)) {
spin_unlock(&unix_table_lock);
/*
* __unix_find_socket_byname() may take long time if many names
@@ -918,7 +917,6 @@ static int unix_autobind(struct socket *sock)
}
goto retry;
}
- addr->hash ^= sk->sk_type;
__unix_set_addr(sk, addr, addr->hash);
spin_unlock(&unix_table_lock);
@@ -965,7 +963,7 @@ static struct sock *unix_find_other(struct net *net,
}
} else {
err = -ECONNREFUSED;
- u = unix_find_socket_byname(net, sunname, len, type, hash);
+ u = unix_find_socket_byname(net, sunname, len, type ^ hash);
if (u) {
struct dentry *dentry;
dentry = unix_sk(u)->path.dentry;
@@ -1036,8 +1034,7 @@ static int unix_bind_bsd(struct sock *sk, struct unix_address *addr)
return err;
}
-static int unix_bind_abstract(struct sock *sk, unsigned hash,
- struct unix_address *addr)
+static int unix_bind_abstract(struct sock *sk, struct unix_address *addr)
{
struct unix_sock *u = unix_sk(sk);
int err;
@@ -1053,7 +1050,7 @@ static int unix_bind_abstract(struct sock *sk, unsigned hash,
spin_lock(&unix_table_lock);
if (__unix_find_socket_byname(sock_net(sk), addr->name, addr->len,
- sk->sk_type, hash)) {
+ addr->hash)) {
spin_unlock(&unix_table_lock);
mutex_unlock(&u->bindlock);
return -EADDRINUSE;
@@ -1096,7 +1093,7 @@ static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
if (sun_path[0])
err = unix_bind_bsd(sk, addr);
else
- err = unix_bind_abstract(sk, hash, addr);
+ err = unix_bind_abstract(sk, addr);
if (err)
unix_release_addr(addr);
return err == -EEXIST ? -EADDRINUSE : err;
--
2.11.0
^ permalink raw reply related [flat|nested] 12+ messages in thread