diff --git a/net/core/sock.c b/net/core/sock.c index d9f0a817dca8..f4b8b78535f8 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -785,6 +785,10 @@ int sock_setsockopt(struct socket *sock, int level, int optname, */ val = min_t(u32, val, sysctl_wmem_max); set_sndbuf: + /* Ensure val * 2 fits into an int, to prevent max_t() + * from treating it as a negative value. + */ + val = min_t(int, val, INT_MAX / 2); sk->sk_userlocks |= SOCK_SNDBUF_LOCK; sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF); /* Wake up sending tasks if we upped the value. */ @@ -796,6 +800,12 @@ set_sndbuf: ret = -EPERM; break; } + + /* No negative values (to prevent underflow, as val will be + * multiplied by 2). + */ + if (val < 0) + val = 0; goto set_sndbuf; case SO_RCVBUF: @@ -806,6 +816,10 @@ set_sndbuf: */ val = min_t(u32, val, sysctl_rmem_max); set_rcvbuf: + /* Ensure val * 2 fits into an int, to prevent max_t() + * from treating it as a negative value. + */ + val = min_t(int, val, INT_MAX / 2); sk->sk_userlocks |= SOCK_RCVBUF_LOCK; /* * We double it on the way in to account for @@ -830,6 +844,12 @@ set_rcvbuf: ret = -EPERM; break; } + + /* No negative values (to prevent underflow, as val will be + * multiplied by 2). + */ + if (val < 0) + val = 0; goto set_rcvbuf; case SO_KEEPALIVE: