commit a477629baa2a0e9991f640af418e8c973a1c08e3 upstream.

While nolibc-test does test syscalls, it doesn't test as much the rest
of the macros, and a wrong spelling of FD_SETBITMASK in commit
feaf75658783a broke programs using either FD_SET() or FD_CLR() without
being noticed. Let's fix these macros.

Fixes: feaf75658783a ("nolibc: fix fd_set type")
Cc: stable@vger.kernel.org # v6.2+
Acked-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit d5094bcb5bfdfea2cf0de8aaf77cc65db56cbdb5 ]

Nolibc assumes that the kernel ABI is using a time values that are as
large as a long integer. For most ABIs this holds true.
But for x32 this is not correct, as it uses 32bit longs but 64bit times.

Also the 'struct stat' implementation of nolibc relies on timespec::tv_sec
and time_t being the same type. While timespec::tv_sec comes from the
kernel and is of type __kernel_old_time_t, time_t is defined within nolibc.

Switch to the __kernel_old_time_t to always get the correct type.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/r/20250712-nolibc-x32-v1-1-6d81cb798710@weissschuh.net
Acked-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 31db7b6a78b7651973c66b7cf479209b20c55290 ]

The compiler does not know that waitid() will only ever return 0 or -1.
If waitid() would return a positive value than waitpid() would return that
same value and *status would not be initialized.
However users calling waitpid() know that the only possible return values
of it are 0 or -1. They therefore might check for errors with
'ret == -1' or 'ret < 0' and use *status otherwise. The compiler will then
warn about the usage of a potentially uninitialized variable.

Example:

	$ cat test.c
	#include <stdio.h>
	#include <unistd.h>

	int main(void)
	{
		int ret, status;

		ret = waitpid(0, &status, 0);
		if (ret == -1)
			return 0;

		printf("status %x\n", status);

		return 0;
	}

	$ gcc --version
	gcc (GCC) 15.1.1 20250425

	$ gcc -Wall -Os -Werror -nostdlib -nostdinc -static -Iusr/include -Itools/include/nolibc/ -o /dev/null test.c
	test.c: In function ‘main’:
	test.c:12:9: error: ‘status’ may be used uninitialized [-Werror=maybe-uninitialized]
	   12 |         printf("status %x\n", status);
	      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
	test.c:6:18: note: ‘status’ was declared here
	    6 |         int ret, status;
	      |                  ^~~~~~
	cc1: all warnings being treated as errors

Avoid the warning by normalizing waitid() errors to '-1' in waitpid().

Fixes: 0c89abf5ab3f ("tools/nolibc: implement waitpid() in terms of waitid()")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20250707-nolibc-waitpid-uninitialized-v1-1-dcd4e70bcd8f@linutronix.de
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 4a40129087a4c32135bb1177a57bbbe6ee646f1a ]

When an error is encountered by printf() it needs to be reported.
errno() is already set by the callback.

sprintf() is different, but that keeps working and is already tested.

Also add a new test.

Fixes: 7e4346f4a3a6 ("tools/nolibc/stdio: add a minimal [vf]printf() implementation")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20250704-nolibc-printf-error-v1-2-74b7a092433b@linutronix.de
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

This is the location regular userspace expects these definitions.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20250515-nolibc-sys-v1-8-74f82eea3b59@weissschuh.net

This is the location regular userspace expects these definitions.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20250515-nolibc-sys-v1-7-74f82eea3b59@weissschuh.net

This is the location regular userspace expects these definitions.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20250515-nolibc-sys-v1-6-74f82eea3b59@weissschuh.net

This is the location regular userspace expects these definitions.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20250515-nolibc-sys-v1-5-74f82eea3b59@weissschuh.net

This is the location regular userspace expects this definition.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20250515-nolibc-sys-v1-4-74f82eea3b59@weissschuh.net

This is the location regular userspace expects this definition.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Willy Tarreau <w@1wt.eu>
Link: https://lore.kernel.org/r/20250515-nolibc-sys-v1-3-74f82eea3b59@weissschuh.net