From 246c713a3655c840337c4b24d3838558673c0d6b Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Thu, 17 Aug 2023 14:03:01 -0700 Subject: [PATCH 1/2] landlock: Annotate struct landlock_rule with __counted_by MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions). As found with Coccinelle[1], add __counted_by for struct landlock_rule. [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci Cc: Paul Moore Cc: James Morris Cc: "Serge E. Hallyn" Cc: linux-security-module@vger.kernel.org Signed-off-by: Kees Cook Reviewed-by: Justin Stitt Reviewed-by: "Gustavo A. R. Silva" Link: https://lore.kernel.org/r/20230817210257.never.920-kees@kernel.org Signed-off-by: Mickaël Salaün --- security/landlock/ruleset.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/security/landlock/ruleset.h b/security/landlock/ruleset.h index d43231b783e4..55b1df8f66a8 100644 --- a/security/landlock/ruleset.h +++ b/security/landlock/ruleset.h @@ -67,7 +67,7 @@ struct landlock_rule { * @layers: Stack of layers, from the latest to the newest, implemented * as a flexible array member (FAM). */ - struct landlock_layer layers[]; + struct landlock_layer layers[] __counted_by(num_layers); }; /** From 2a2015495142ee0a35711b5dcf7b215c31489f27 Mon Sep 17 00:00:00 2001 From: Ding Xiang Date: Wed, 30 Aug 2023 18:11:48 +0800 Subject: [PATCH 2/2] selftests/landlock: Fix a resource leak MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The opened file should be closed before return, otherwise resource leak will occur. Signed-off-by: Ding Xiang Link: https://lore.kernel.org/r/20230830101148.3738-1-dingxiang@cmss.chinamobile.com Fixes: 3de64b656b3c ("selftests/landlock: Add supports_filesystem() helper") Signed-off-by: Mickaël Salaün --- tools/testing/selftests/landlock/fs_test.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/tools/testing/selftests/landlock/fs_test.c b/tools/testing/selftests/landlock/fs_test.c index 83d565569512..251594306d40 100644 --- a/tools/testing/selftests/landlock/fs_test.c +++ b/tools/testing/selftests/landlock/fs_test.c @@ -113,7 +113,7 @@ static bool supports_filesystem(const char *const filesystem) { char str[32]; int len; - bool res; + bool res = true; FILE *const inf = fopen("/proc/filesystems", "r"); /* @@ -125,14 +125,16 @@ static bool supports_filesystem(const char *const filesystem) /* filesystem can be null for bind mounts. */ if (!filesystem) - return true; + goto out; len = snprintf(str, sizeof(str), "nodev\t%s\n", filesystem); if (len >= sizeof(str)) /* Ignores too-long filesystem names. */ - return true; + goto out; res = fgrep(inf, str); + +out: fclose(inf); return res; }