Re: [PATCH 06/11] sysctl: Add size to register_net_sysctl function

[Dan Carpenter]

On Wed, Jun 21, 2023 at 12:47:30PM +0300, Dan Carpenter wrote:
> The patchset doesn't include the actual interesting changes, just a
> bunch of mechanical prep work.
> 

I was wrong here, the patchset just hadn't all hit the mailing lists.
I can't apply this patchset to anything.  I tried linux-next, net, and
net-next.  So it's hard to review.

It looks like ensure_safe_net_sysctl() never got update to use
table_size...

You could easily write a static checker test to print a warning any time
that ->procname is checked for NULL.  I have attached a Smatch check.
You would need to added to check_list.h and recompile.

net/sysctl_net.c:130 ensure_safe_net_sysctl() warn: checking ->procname 'ent->procname'

regards,
dan carpenter

#include "smatch.h"
#include "smatch_slist.h"

static int my_id;

static void match_condition(struct expression *expr)
{
	char *member_name;

	if (expr->type == EXPR_COMPARE)
		return;

	member_name = get_member_name(expr);
	if (!member_name)
		return;

	if (strcmp(member_name, "(struct ctl_table)->procname") == 0)
		sm_warning("checking ->procname '%s'", expr_to_str(expr));
}

void check_checking_procname(int id)
{
	my_id = id;

	add_hook(&match_condition, CONDITION_HOOK);
}