On 17-06-11 09:49 AM, Jiri Pirko wrote:

Sun, Jun 11, 2017 at 01:53:43PM CEST, jhs@mojatatu.com wrote:

quoted

From: Jamal Hadi Salim <jhs@mojatatu.com>

quoted

This patch also provides an extra feature: a validation callback
that could be speaciliazed for other types.

s/speaciliazed/speciliazed/

Will fix.

quoted

[ATTR_GOO] = { .type = MYTYPE,
	       .validation_data = &myvalidation_data,
               .validate_content = mycontent_validator },

Indent is wrong. (Does not matter really in desc, but anyway)

I cant find out how it got indented that way; my source
or email dont show it as such (but really doesnt matter).

Suggested-by: Jiri Pirko <redacted>

Will add.

quoted

---
include/net/netlink.h          | 11 +++++++++++
include/uapi/linux/rtnetlink.h | 17 +++++++++++++++++
lib/nlattr.c                   | 25 +++++++++++++++++++++++++
3 files changed, 53 insertions(+)

diff --git a/include/net/netlink.h b/include/net/netlink.h
index 0170917..8ab9784 100644
--- a/include/net/netlink.h
+++ b/include/net/netlink.h

@@ -6,6 +6,11 @@

#include <linux/jiffies.h>
#include <linux/in6.h>

+struct nla_bit_flags {
+	u32 nla_flag_values;
+	u32 nla_flag_selector;
+};

I don't understand why you redefine the struct here. You already have it
defined in the uapi: struct __nla_bit_flags

Just move this (struct nla_bit_flags) to the uapi and remove
__nla_bit_flags ?

I am not sure that will compile since the type is defined in netlink.h
Also, note: uapi uses _u32 and kernel uses u32 as types i.e it is pretty
common approach; i will try to move it to uapi and keep that uapi
format. If it doesnt compile without acrobatics I will keep it as is.

quoted

+

quoted

diff --git a/lib/nlattr.c b/lib/nlattr.c
index a7e0b16..78fed43 100644
--- a/lib/nlattr.c
+++ b/lib/nlattr.c

@@ -27,6 +27,21 @@

	[NLA_S64]	= sizeof(s64),
};

+static int validate_nla_bit_flags(const struct nlattr *nla, void *valid_data)
+{
+	const struct nla_bit_flags *nbf = nla_data(nla);
+	u32 *valid_flags_mask = valid_data;
+
+	if (!valid_data)
+		return -EINVAL;
+
+

Avoid one empty line here (you have 2)

Will fix.

quoted

+	if (nbf->nla_flag_values & ~*valid_flags_mask)
+		return -EINVAL;
+
+	return 0;
+}
+
static int validate_nla(const struct nlattr *nla, int maxtype,
			const struct nla_policy *policy)
{

@@ -46,6 +61,13 @@ static int validate_nla(const struct nlattr *nla, int maxtype,

			return -ERANGE;
		break;

+	case NLA_FLAG_BITS:
+		if (attrlen != 8) /* 2 x 32 bits */

sizeof(struct nla_bit_flags) instead of 8 please, you can skip the
comment then.

Good point.

quoted

+			return -ERANGE;
+
+		return validate_nla_bit_flags(nla, pt->validation_data);
+		break;
+
	case NLA_NUL_STRING:
		if (pt->len)
			minlen = min_t(int, attrlen, pt->len + 1);

@@ -103,6 +125,9 @@ static int validate_nla(const struct nlattr *nla, int maxtype,

			return -ERANGE;
	}

+	if (pt->validate_content)
+		return pt->validate_content(nla, pt->validation_data);

This validation mechanism is completely independent from the added NLA_FLAG_BITS
attr as it could be used with other attribute types. Please have it as a
separate patch.

Ok - so one more patch then ;->

cheers,
jamal