From a4b35d4d05b9f2e84c1dd6301d3dca65719334ef Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Thu, 17 Aug 2023 14:03:28 -0700 Subject: integrity: Annotate struct ima_rule_opt_list with __counted_by 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 ima_rule_opt_list. Additionally, since the element count member must be set before accessing the annotated flexible array member, move its initialization earlier. [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci Cc: Mimi Zohar Cc: Dmitry Kasatkin Cc: Paul Moore Cc: James Morris Cc: "Serge E. Hallyn" Cc: linux-integrity@vger.kernel.org Cc: linux-security-module@vger.kernel.org Acked-by: Mimi Zohar Reviewed-by: "Gustavo A. R. Silva" Acked-by: Jarkko Sakkinen Link: https://lore.kernel.org/r/20230817210327.never.598-kees@kernel.org Signed-off-by: Kees Cook --- security/integrity/ima/ima_policy.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'security') diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index c9b3bd8f1bb9..7a0420cf1a6a 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -68,7 +68,7 @@ enum policy_rule_list { IMA_DEFAULT_POLICY = 1, IMA_CUSTOM_POLICY }; struct ima_rule_opt_list { size_t count; - char *items[]; + char *items[] __counted_by(count); }; /* @@ -342,6 +342,7 @@ static struct ima_rule_opt_list *ima_alloc_rule_opt_list(const substring_t *src) kfree(src_copy); return ERR_PTR(-ENOMEM); } + opt_list->count = count; /* * strsep() has already replaced all instances of '|' with '\0', @@ -357,7 +358,6 @@ static struct ima_rule_opt_list *ima_alloc_rule_opt_list(const substring_t *src) opt_list->items[i] = cur; cur = strchr(cur, '\0') + 1; } - opt_list->count = count; return opt_list; } -- cgit v1.2.3