[PATCH v4 6/7] samples/landlock: Add support for LANDLOCK_ACCESS_FS_IOCTL

[Günther Noack]

Add ioctl support to the Landlock sample tool.

The ioctl right is grouped with the read-write rights in the sample
tool, as some ioctl requests provide features that mutate state.

Signed-off-by: Günther Noack <gnoack at google.com>
---
 samples/landlock/sandboxer.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/samples/landlock/sandboxer.c b/samples/landlock/sandboxer.c
index 08596c0ef070..a4b2bebaf203 100644
--- a/samples/landlock/sandboxer.c
+++ b/samples/landlock/sandboxer.c
@@ -81,7 +81,8 @@ static int parse_path(char *env_path, const char ***const path_list)
 	LANDLOCK_ACCESS_FS_EXECUTE | \
 	LANDLOCK_ACCESS_FS_WRITE_FILE | \
 	LANDLOCK_ACCESS_FS_READ_FILE | \
-	LANDLOCK_ACCESS_FS_TRUNCATE)
+	LANDLOCK_ACCESS_FS_TRUNCATE | \
+	LANDLOCK_ACCESS_FS_IOCTL)
 
 /* clang-format on */
 
@@ -199,7 +200,8 @@ static int populate_ruleset_net(const char *const env_var, const int ruleset_fd,
 	LANDLOCK_ACCESS_FS_MAKE_BLOCK | \
 	LANDLOCK_ACCESS_FS_MAKE_SYM | \
 	LANDLOCK_ACCESS_FS_REFER | \
-	LANDLOCK_ACCESS_FS_TRUNCATE)
+	LANDLOCK_ACCESS_FS_TRUNCATE | \
+	LANDLOCK_ACCESS_FS_IOCTL)
 
 /* clang-format on */
 
@@ -317,6 +319,10 @@ int main(const int argc, char *const argv[], char *const *const envp)
 		ruleset_attr.handled_access_net &=
 			~(LANDLOCK_ACCESS_NET_BIND_TCP |
 			  LANDLOCK_ACCESS_NET_CONNECT_TCP);
+	case 4:
+		/* Removes LANDLOCK_ACCESS_FS_IOCTL for ABI < 5 */
+		ruleset_attr.handled_access_fs &= ~LANDLOCK_ACCESS_FS_IOCTL;
+
 		fprintf(stderr,
 			"Hint: You should update the running kernel "
 			"to leverage Landlock features "
-- 
2.42.0.869.gea05f2083d-goog