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Diffstat (limited to 'net/unix')
-rw-r--r--net/unix/af_unix.c49
-rw-r--r--net/unix/diag.c2
-rw-r--r--net/unix/garbage.c17
3 files changed, 46 insertions, 22 deletions
diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 8badff627fef..6579fd6e7459 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -315,7 +315,7 @@ static struct sock *unix_find_socket_byinode(struct inode *i)
&unix_socket_table[i->i_ino & (UNIX_HASH_SIZE - 1)]) {
struct dentry *dentry = unix_sk(s)->path.dentry;
- if (dentry && d_backing_inode(dentry) == i) {
+ if (dentry && d_real_inode(dentry) == i) {
sock_hold(s);
goto found;
}
@@ -911,7 +911,7 @@ static struct sock *unix_find_other(struct net *net,
err = kern_path(sunname->sun_path, LOOKUP_FOLLOW, &path);
if (err)
goto fail;
- inode = d_backing_inode(path.dentry);
+ inode = d_real_inode(path.dentry);
err = inode_permission(inode, MAY_WRITE);
if (err)
goto put_fail;
@@ -1048,7 +1048,7 @@ static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
goto out_up;
}
addr->hash = UNIX_HASH_SIZE;
- hash = d_backing_inode(dentry)->i_ino & (UNIX_HASH_SIZE - 1);
+ hash = d_real_inode(dentry)->i_ino & (UNIX_HASH_SIZE - 1);
spin_lock(&unix_table_lock);
u->path = u_path;
list = &unix_socket_table[hash];
@@ -1496,7 +1496,7 @@ static void unix_detach_fds(struct scm_cookie *scm, struct sk_buff *skb)
UNIXCB(skb).fp = NULL;
for (i = scm->fp->count-1; i >= 0; i--)
- unix_notinflight(scm->fp->fp[i]);
+ unix_notinflight(scm->fp->user, scm->fp->fp[i]);
}
static void unix_destruct_scm(struct sk_buff *skb)
@@ -1513,6 +1513,21 @@ static void unix_destruct_scm(struct sk_buff *skb)
sock_wfree(skb);
}
+/*
+ * The "user->unix_inflight" variable is protected by the garbage
+ * collection lock, and we just read it locklessly here. If you go
+ * over the limit, there might be a tiny race in actually noticing
+ * it across threads. Tough.
+ */
+static inline bool too_many_unix_fds(struct task_struct *p)
+{
+ struct user_struct *user = current_user();
+
+ if (unlikely(user->unix_inflight > task_rlimit(p, RLIMIT_NOFILE)))
+ return !capable(CAP_SYS_RESOURCE) && !capable(CAP_SYS_ADMIN);
+ return false;
+}
+
#define MAX_RECURSION_LEVEL 4
static int unix_attach_fds(struct scm_cookie *scm, struct sk_buff *skb)
@@ -1521,6 +1536,9 @@ static int unix_attach_fds(struct scm_cookie *scm, struct sk_buff *skb)
unsigned char max_level = 0;
int unix_sock_count = 0;
+ if (too_many_unix_fds(current))
+ return -ETOOMANYREFS;
+
for (i = scm->fp->count - 1; i >= 0; i--) {
struct sock *sk = unix_get_socket(scm->fp->fp[i]);
@@ -1542,10 +1560,8 @@ static int unix_attach_fds(struct scm_cookie *scm, struct sk_buff *skb)
if (!UNIXCB(skb).fp)
return -ENOMEM;
- if (unix_sock_count) {
- for (i = scm->fp->count - 1; i >= 0; i--)
- unix_inflight(scm->fp->fp[i]);
- }
+ for (i = scm->fp->count - 1; i >= 0; i--)
+ unix_inflight(scm->fp->user, scm->fp->fp[i]);
return max_level;
}
@@ -2259,13 +2275,15 @@ static int unix_stream_read_generic(struct unix_stream_read_state *state)
size_t size = state->size;
unsigned int last_len;
- err = -EINVAL;
- if (sk->sk_state != TCP_ESTABLISHED)
+ if (unlikely(sk->sk_state != TCP_ESTABLISHED)) {
+ err = -EINVAL;
goto out;
+ }
- err = -EOPNOTSUPP;
- if (flags & MSG_OOB)
+ if (unlikely(flags & MSG_OOB)) {
+ err = -EOPNOTSUPP;
goto out;
+ }
target = sock_rcvlowat(sk, flags & MSG_WAITALL, size);
timeo = sock_rcvtimeo(sk, noblock);
@@ -2311,9 +2329,11 @@ again:
goto unlock;
unix_state_unlock(sk);
- err = -EAGAIN;
- if (!timeo)
+ if (!timeo) {
+ err = -EAGAIN;
break;
+ }
+
mutex_unlock(&u->readlock);
timeo = unix_stream_data_wait(sk, timeo, last,
@@ -2321,6 +2341,7 @@ again:
if (signal_pending(current)) {
err = sock_intr_errno(timeo);
+ scm_destroy(&scm);
goto out;
}
diff --git a/net/unix/diag.c b/net/unix/diag.c
index c512f64d5287..4d9679701a6d 100644
--- a/net/unix/diag.c
+++ b/net/unix/diag.c
@@ -220,7 +220,7 @@ done:
return skb->len;
}
-static struct sock *unix_lookup_by_ino(int ino)
+static struct sock *unix_lookup_by_ino(unsigned int ino)
{
int i;
struct sock *sk;
diff --git a/net/unix/garbage.c b/net/unix/garbage.c
index a73a226f2d33..6a0d48525fcf 100644
--- a/net/unix/garbage.c
+++ b/net/unix/garbage.c
@@ -116,15 +116,15 @@ struct sock *unix_get_socket(struct file *filp)
* descriptor if it is for an AF_UNIX socket.
*/
-void unix_inflight(struct file *fp)
+void unix_inflight(struct user_struct *user, struct file *fp)
{
struct sock *s = unix_get_socket(fp);
+ spin_lock(&unix_gc_lock);
+
if (s) {
struct unix_sock *u = unix_sk(s);
- spin_lock(&unix_gc_lock);
-
if (atomic_long_inc_return(&u->inflight) == 1) {
BUG_ON(!list_empty(&u->link));
list_add_tail(&u->link, &gc_inflight_list);
@@ -132,25 +132,28 @@ void unix_inflight(struct file *fp)
BUG_ON(list_empty(&u->link));
}
unix_tot_inflight++;
- spin_unlock(&unix_gc_lock);
}
+ user->unix_inflight++;
+ spin_unlock(&unix_gc_lock);
}
-void unix_notinflight(struct file *fp)
+void unix_notinflight(struct user_struct *user, struct file *fp)
{
struct sock *s = unix_get_socket(fp);
+ spin_lock(&unix_gc_lock);
+
if (s) {
struct unix_sock *u = unix_sk(s);
- spin_lock(&unix_gc_lock);
BUG_ON(list_empty(&u->link));
if (atomic_long_dec_and_test(&u->inflight))
list_del_init(&u->link);
unix_tot_inflight--;
- spin_unlock(&unix_gc_lock);
}
+ user->unix_inflight--;
+ spin_unlock(&unix_gc_lock);
}
static void scan_inflight(struct sock *x, void (*func)(struct unix_sock *),
generated by cgit v1.2.3 (git 2.25.1) at 2025-10-23 13:49:08 +0000