Author: brooks Date: Thu Apr 13 15:52:45 2017 New Revision: 316768 URL: https://svnweb.freebsd.org/changeset/base/316768
Log: Fix an out-of-bounds write when a zero-length buffer is passed. Found with ttyname_test and CHERI bounds checking. Reviewed by: emaste Obtained from: CheriBSD MFC after: 1 week Sponsored by: DARPA, AFRL Differential Revision: https://reviews.freebsd.org/D10377 Modified: head/lib/libc/gen/ttyname.c Modified: head/lib/libc/gen/ttyname.c ============================================================================== --- head/lib/libc/gen/ttyname.c Thu Apr 13 15:49:55 2017 (r316767) +++ head/lib/libc/gen/ttyname.c Thu Apr 13 15:52:45 2017 (r316768) @@ -61,6 +61,10 @@ ttyname_r(int fd, char *buf, size_t len) { size_t used; + /* Don't write off the end of a zero-length buffer. */ + if (len < 1) + return (ERANGE); + *buf = '\0'; /* Must be a terminal. */ _______________________________________________ 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"
