verrx() passes its va_list to the variadic warnx() instead of vwarnx(), so errx() and verrx() print their messages with the wrong arguments, and can crash when the format has a "%s".
Patch 1 fixes it. Patch 2 adds a nolibc-test case for errx(), which would have caught it. The series is independent of the readdir_r()/FD_* series [1] and merges cleanly with it. Tested on top of nolibc/for-next 61fb00d6efee, on x86_64 and i386, and on arm, arm64 and sparc64 under qemu-user: - nolibc-test, all tests: no failures with the series. The only difference from before is the new errx test, which passes. It also passes against glibc (make libc-test). - Without patch 1, the errx test fails on all five. On x86_64 the child is killed by SIGSEGV. [1] https://lore.kernel.org/all/[email protected]/ Danish Khateeb (2): tools/nolibc: fix verrx() and errx() message formatting selftests/nolibc: add a test for errx() tools/include/nolibc/err.h | 2 +- tools/testing/selftests/nolibc/nolibc-test.c | 47 ++++++++++++++++++++ 2 files changed, 48 insertions(+), 1 deletion(-) base-commit: 61fb00d6efeeeb9fd65c81db3bd8b2ac140f573c -- 2.55.0
