git: 91ea7e2ce2b5 - main - libc: fix the _FORTIFY_SOURCE build of getgrouplist(3)

The branch main has been updated by kevans:

URL: https://cgit.FreeBSD.org/src/commit/?id=91ea7e2ce2b5b2ff4702c3092cfe944862d58172

commit 91ea7e2ce2b5b2ff4702c3092cfe944862d58172
Author:     Kyle Evans <kevans@FreeBSD.org>
AuthorDate: 2025-09-13 22:19:46 +0000
Commit:     Kyle Evans <kevans@FreeBSD.org>
CommitDate: 2025-09-13 22:19:46 +0000

    libc: fix the _FORTIFY_SOURCE build of getgrouplist(3)
    
    We need <unistd.h> to get our prototype normally, but WARNS in libc is
    way too low to surface that.
    
    Additionally, _FORTIFY_SOURCE needs to include <ssp/unistd.h> by way of
    <unistd.h> to actually export an implementation of getgrouplist(3).  The
    version defined in the .c gets named __ssp_real_getgrouplist() and the
    actual implementation comes from the redirect stub in <ssp/unistd.h>,
    which basically gets optimized away in the built object because our
    __builtin_object_size() check is trivially false when we cannot resolve
    any object sizes in this translation unit.
    
    This could be argued as a design flaw in _FORTIFY_SOURCE, but we should
    grab <unistd.h> for our prototype anyways so let's kick the can down
    the road instead of re-thinking it for 15.0.
    
    Reported by:    Shawn Webb (HardenedBSD)
    Fixes:          d3f8ed6066 ("getgrouplist(3): Remove superfluous [...]")
    MFC after:      3 days
---
 lib/libc/gen/getgrouplist.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/libc/gen/getgrouplist.c b/lib/libc/gen/getgrouplist.c
index cb23b9b2316d..9c57b7031336 100644
--- a/lib/libc/gen/getgrouplist.c
+++ b/lib/libc/gen/getgrouplist.c
@@ -31,6 +31,7 @@
 
 #include <sys/types.h>
 
+#include <unistd.h>
 #include <ssp/ssp.h>
 
 extern int __getgroupmembership(const char *, gid_t, gid_t *, int, int *);