diff mbox series

[RFC,net-next] taprio: validate TCA_TAPRIO_ATTR_FLAGS through policy instead of open-coding

Message ID 20240104163856.16699-1-alessandromarcolini99@gmail.com (mailing list archive)
State RFC
Delegated to: Netdev Maintainers
Headers show
Series [RFC,net-next] taprio: validate TCA_TAPRIO_ATTR_FLAGS through policy instead of open-coding | expand

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Context Check Description
netdev/series_format success Single patches do not need cover letters
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 1113 this patch: 1113
netdev/cc_maintainers warning 1 maintainers not CCed: vinicius.gomes@intel.com
netdev/build_clang success Errors and warnings before: 1140 this patch: 1140
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 1140 this patch: 1140
netdev/checkpatch warning WARNING: line length of 100 exceeds 80 columns WARNING: line length of 94 exceeds 80 columns WARNING: line length of 98 exceeds 80 columns
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Alessandro Marcolini Jan. 4, 2024, 4:38 p.m. UTC
As of now, the field TCA_TAPRIO_ATTR_FLAGS is being validated by manually
checking its value, using the function taprio_flags_valid().

With this patch, the field will be validated through the netlink policy
NLA_POLICY_MASK, where the mask is defined by TAPRIO_SUPPORTED_FLAGS.
The mutual exclusivity of the two flags TCA_TAPRIO_ATTR_FLAG_FULL_OFFLOAD
and TCA_TAPRIO_ATTR_FLAG_TXTIME_ASSIST is still checked manually.

Signed-off-by: Alessandro Marcolini <alessandromarcolini99@gmail.com>
---
 net/sched/sch_taprio.c | 70 +++++++++++++++---------------------------
 1 file changed, 24 insertions(+), 46 deletions(-)
diff mbox series

Patch

diff --git a/net/sched/sch_taprio.c b/net/sched/sch_taprio.c
index 31a8252bd09c..8766934c4f00 100644
--- a/net/sched/sch_taprio.c
+++ b/net/sched/sch_taprio.c
@@ -40,6 +40,8 @@  static struct static_key_false taprio_have_working_mqprio;
 
 #define TXTIME_ASSIST_IS_ENABLED(flags) ((flags) & TCA_TAPRIO_ATTR_FLAG_TXTIME_ASSIST)
 #define FULL_OFFLOAD_IS_ENABLED(flags) ((flags) & TCA_TAPRIO_ATTR_FLAG_FULL_OFFLOAD)
+#define TAPRIO_SUPPORTED_FLAGS \
+	(TCA_TAPRIO_ATTR_FLAG_TXTIME_ASSIST | TCA_TAPRIO_ATTR_FLAG_FULL_OFFLOAD)
 #define TAPRIO_FLAGS_INVALID U32_MAX
 
 struct sched_entry {
@@ -408,19 +410,6 @@  static bool is_valid_interval(struct sk_buff *skb, struct Qdisc *sch)
 	return entry;
 }
 
-static bool taprio_flags_valid(u32 flags)
-{
-	/* Make sure no other flag bits are set. */
-	if (flags & ~(TCA_TAPRIO_ATTR_FLAG_TXTIME_ASSIST |
-		      TCA_TAPRIO_ATTR_FLAG_FULL_OFFLOAD))
-		return false;
-	/* txtime-assist and full offload are mutually exclusive */
-	if ((flags & TCA_TAPRIO_ATTR_FLAG_TXTIME_ASSIST) &&
-	    (flags & TCA_TAPRIO_ATTR_FLAG_FULL_OFFLOAD))
-		return false;
-	return true;
-}
-
 /* This returns the tstamp value set by TCP in terms of the set clock. */
 static ktime_t get_tcp_tstamp(struct taprio_sched *q, struct sk_buff *skb)
 {
@@ -1031,7 +1020,8 @@  static const struct nla_policy taprio_policy[TCA_TAPRIO_ATTR_MAX + 1] = {
 	[TCA_TAPRIO_ATTR_SCHED_CYCLE_TIME]           =
 		NLA_POLICY_FULL_RANGE_SIGNED(NLA_S64, &taprio_cycle_time_range),
 	[TCA_TAPRIO_ATTR_SCHED_CYCLE_TIME_EXTENSION] = { .type = NLA_S64 },
-	[TCA_TAPRIO_ATTR_FLAGS]                      = { .type = NLA_U32 },
+	[TCA_TAPRIO_ATTR_FLAGS]                      =
+		NLA_POLICY_MASK(NLA_U32, TAPRIO_SUPPORTED_FLAGS),
 	[TCA_TAPRIO_ATTR_TXTIME_DELAY]		     = { .type = NLA_U32 },
 	[TCA_TAPRIO_ATTR_TC_ENTRY]		     = { .type = NLA_NESTED },
 };
@@ -1815,33 +1805,6 @@  static int taprio_mqprio_cmp(const struct net_device *dev,
 	return 0;
 }
 
-/* The semantics of the 'flags' argument in relation to 'change()'
- * requests, are interpreted following two rules (which are applied in
- * this order): (1) an omitted 'flags' argument is interpreted as
- * zero; (2) the 'flags' of a "running" taprio instance cannot be
- * changed.
- */
-static int taprio_new_flags(const struct nlattr *attr, u32 old,
-			    struct netlink_ext_ack *extack)
-{
-	u32 new = 0;
-
-	if (attr)
-		new = nla_get_u32(attr);
-
-	if (old != TAPRIO_FLAGS_INVALID && old != new) {
-		NL_SET_ERR_MSG_MOD(extack, "Changing 'flags' of a running schedule is not supported");
-		return -EOPNOTSUPP;
-	}
-
-	if (!taprio_flags_valid(new)) {
-		NL_SET_ERR_MSG_MOD(extack, "Specified 'flags' are not valid");
-		return -EINVAL;
-	}
-
-	return new;
-}
-
 static int taprio_change(struct Qdisc *sch, struct nlattr *opt,
 			 struct netlink_ext_ack *extack)
 {
@@ -1854,6 +1817,7 @@  static int taprio_change(struct Qdisc *sch, struct nlattr *opt,
 	unsigned long flags;
 	ktime_t start;
 	int i, err;
+	__u32 taprio_flags;
 
 	err = nla_parse_nested_deprecated(tb, TCA_TAPRIO_ATTR_MAX, opt,
 					  taprio_policy, extack);
@@ -1863,12 +1827,26 @@  static int taprio_change(struct Qdisc *sch, struct nlattr *opt,
 	if (tb[TCA_TAPRIO_ATTR_PRIOMAP])
 		mqprio = nla_data(tb[TCA_TAPRIO_ATTR_PRIOMAP]);
 
-	err = taprio_new_flags(tb[TCA_TAPRIO_ATTR_FLAGS],
-			       q->flags, extack);
-	if (err < 0)
-		return err;
+	/* The semantics of the 'flags' argument in relation to 'change()'
+	 * requests, are interpreted following two rules (which are applied in
+	 * this order): (1) an omitted 'flags' argument is interpreted as
+	 * zero; (2) the 'flags' of a "running" taprio instance cannot be
+	 * changed.
+	 */
+	taprio_flags = tb[TCA_TAPRIO_ATTR_FLAGS] ? nla_get_u32(tb[TCA_TAPRIO_ATTR_FLAGS]) : 0;
 
-	q->flags = err;
+	/* txtime-assist and full offload are mutually exclusive */
+	if ((taprio_flags & TCA_TAPRIO_ATTR_FLAG_TXTIME_ASSIST) &&
+	    (taprio_flags & TCA_TAPRIO_ATTR_FLAG_FULL_OFFLOAD)) {
+		NL_SET_ERR_MSG_MOD(extack, "TXTIME_ASSIST and FULL_OFFLOAD are mutually exclusive");
+		return -EINVAL;
+	}
+
+	if (q->flags != TAPRIO_FLAGS_INVALID && q->flags != taprio_flags) {
+		NL_SET_ERR_MSG(extack, "Changing 'flags' of a running schedule is not supported");
+		return -EOPNOTSUPP;
+	}
+	q->flags = taprio_flags;
 
 	err = taprio_parse_mqprio_opt(dev, mqprio, extack, q->flags);
 	if (err < 0)