From a0094dc136c35e8602f5a01a34904e4e5e2e6b19 Mon Sep 17 00:00:00 2001 From: Federico Serafini Date: Mon, 30 Sep 2024 14:49:16 +0200 Subject: [PATCH] xen/gnttab: address a violation of MISRA C Rule 13.6 guest_handle_ok()'s expansion contains a sizeof() involving its first argument guest_handle_cast(). The expansion of the latter, in turn, contains a variable initialization. Since MISRA considers the initialization (even of a local variable) a side effect, the chain of expansions mentioned above violates MISRA C:2012 Rule 13.6 (The operand of the `sizeof' operator shall not contain any expression which has potential side effect). Refactor the code to address the rule violation. Suggested-by: Andrew Cooper Signed-off-by: Federico Serafini Reviewed-by: Stefano Stabellini --- xen/common/compat/grant_table.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/xen/common/compat/grant_table.c b/xen/common/compat/grant_table.c index 5ad0debf96..bbb717bf64 100644 --- a/xen/common/compat/grant_table.c +++ b/xen/common/compat/grant_table.c @@ -78,12 +78,15 @@ int compat_grant_table_op( cmd_op = cmd; switch ( cmd_op ) { -#define CASE(name) \ - case GNTTABOP_##name: \ - if ( unlikely(!guest_handle_okay(guest_handle_cast(uop, \ - gnttab_##name##_compat_t), \ - count)) ) \ - rc = -EFAULT; \ +#define CASE(name) \ + case GNTTABOP_ ## name: \ + { \ + XEN_GUEST_HANDLE_PARAM(gnttab_ ## name ## _compat_t) h = \ + guest_handle_cast(uop, gnttab_ ## name ## _compat_t); \ + \ + if ( unlikely(!guest_handle_okay(h, count)) ) \ + rc = -EFAULT; \ + } \ break #ifndef CHECK_gnttab_map_grant_ref