Author: tuexen Date: Sun Jul 14 21:44:18 2019 New Revision: 349989 URL: https://svnweb.freebsd.org/changeset/base/349989
Log: Improve the input validation for l_linger. When using the SOL_SOCKET level socket option SO_LINGER, the structure struct linger is used as the option value. The component l_linger is of type int, but internally copied to the field so_linger of the structure struct socket. The type of so_linger is short, but it is assumed to be non-negative and the value is used to compute ticks to be stored in a variable of type int. Therefore, perform input validation on l_linger similar to the one performed by NetBSD and OpenBSD. Thanks to syzkaller for making me aware of this issue. Thanks to markj@ for pointing out that a similar check should be added to so_linger_set(). Reviewed by: markj@ MFC after: 2 weeks Differential Revision: https://reviews.freebsd.org/D20948 Modified: head/sys/kern/uipc_socket.c Modified: head/sys/kern/uipc_socket.c ============================================================================== --- head/sys/kern/uipc_socket.c Sun Jul 14 21:08:54 2019 (r349988) +++ head/sys/kern/uipc_socket.c Sun Jul 14 21:44:18 2019 (r349989) @@ -2776,7 +2776,12 @@ sosetopt(struct socket *so, struct sockopt *sopt) error = sooptcopyin(sopt, &l, sizeof l, sizeof l); if (error) goto bad; - + if (l.l_linger < 0 || + l.l_linger > USHRT_MAX || + l.l_linger > (INT_MAX / hz)) { + error = EDOM; + goto bad; + } SOCK_LOCK(so); so->so_linger = l.l_linger; if (l.l_onoff) @@ -4105,6 +4110,9 @@ so_linger_get(const struct socket *so) void so_linger_set(struct socket *so, int val) { + + KASSERT(val >= 0 && val <= USHRT_MAX && val <= (INT_MAX / hz), + ("%s: val %d out of range", __func__, val)); so->so_linger = val; } _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
