[PATCH] generic/633: adapt execveat() invocations

[Christian Brauner <brauner@kernel.org>]

There's a push by Ariadne to enforce that argv[0] cannot be NULL. So far
we've allowed this. Fix the execveat() invocations to set argv[0] to the
name of the file we're about to execute.

Cc: Ariadne Conill <ariadne@dereferenced.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Eryu Guan <guaneryu@gmail.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: fstests@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Link: https://lore.kernel.org/lkml/20220127000724.15106-1-ariadne@dereferenced.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
---
 src/idmapped-mounts/idmapped-mounts.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/src/idmapped-mounts/idmapped-mounts.c b/src/idmapped-mounts/idmapped-mounts.c
index 4cf6c3bb..76b559ae 100644
--- a/src/idmapped-mounts/idmapped-mounts.c
+++ b/src/idmapped-mounts/idmapped-mounts.c
@@ -3598,7 +3598,7 @@ static int setid_binaries(void)
 			NULL,
 		};
 		static char *argv[] = {
-			NULL,
+			"",
 		};
 
 		if (!expected_uid_gid(t_dir1_fd, FILE1, 0, 5000, 5000))
@@ -3726,7 +3726,7 @@ static int setid_binaries_idmapped_mounts(void)
 			NULL,
 		};
 		static char *argv[] = {
-			NULL,
+			"",
 		};
 
 		if (!expected_uid_gid(open_tree_fd, FILE1, 0, 15000, 15000))
@@ -3865,7 +3865,7 @@ static int setid_binaries_idmapped_mounts_in_userns(void)
 			NULL,
 		};
 		static char *argv[] = {
-			NULL,
+			"",
 		};
 
 		if (!switch_userns(attr.userns_fd, 0, 0, false))
@@ -3924,7 +3924,7 @@ static int setid_binaries_idmapped_mounts_in_userns(void)
 			NULL,
 		};
 		static char *argv[] = {
-			NULL,
+			"",
 		};
 
 		if (!caps_supported()) {
@@ -3992,7 +3992,7 @@ static int setid_binaries_idmapped_mounts_in_userns(void)
 			NULL,
 		};
 		static char *argv[] = {
-			NULL,
+			"",
 		};
 
 		if (!switch_userns(attr.userns_fd, 0, 0, false))
@@ -4150,7 +4150,7 @@ static int setid_binaries_idmapped_mounts_in_userns_separate_userns(void)
 			NULL,
 		};
 		static char *argv[] = {
-			NULL,
+			"",
 		};
 
 		userns_fd = get_userns_fd(0, 10000, 10000);
@@ -4214,7 +4214,7 @@ static int setid_binaries_idmapped_mounts_in_userns_separate_userns(void)
 			NULL,
 		};
 		static char *argv[] = {
-			NULL,
+			"",
 		};
 
 		userns_fd = get_userns_fd(0, 10000, 10000);
@@ -4286,7 +4286,7 @@ static int setid_binaries_idmapped_mounts_in_userns_separate_userns(void)
 			NULL,
 		};
 		static char *argv[] = {
-			NULL,
+			"",
 		};
 
 		userns_fd = get_userns_fd(0, 10000, 10000);

base-commit: d8dee1222ecdfa1cff1386a61248e587eb3b275d
-- 
2.32.0