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From:   Sasha Levin <sashal@kernel.org>
To:     linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc:     Ido Schimmel <idosch@nvidia.com>,
        gushengxian <gushengxian@yulong.com>,
        Jamal Hadi Salim <jhs@mojatatu.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Sasha Levin <sashal@kernel.org>
Subject: [PATCH 5.10 72/98] Revert "flow_offload: action should not be NULL when it is referenced"
Date:   Tue, 24 Aug 2021 12:58:42 -0400
Message-Id: <20210824165908.709932-73-sashal@kernel.org>
In-Reply-To: <20210824165908.709932-1-sashal@kernel.org>
References: <20210824165908.709932-1-sashal@kernel.org>
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From: Ido Schimmel <idosch@nvidia.com>

[ Upstream commit fa05bdb89b01b098aad19ec0ebc4d1cc7b11177e ]

This reverts commit 9ea3e52c5bc8bb4a084938dc1e3160643438927a.

Cited commit added a check to make sure 'action' is not NULL, but
'action' is already dereferenced before the check, when calling
flow_offload_has_one_action().

Therefore, the check does not make any sense and results in a smatch
warning:

include/net/flow_offload.h:322 flow_action_mixed_hw_stats_check() warn:
variable dereferenced before check 'action' (see line 319)

Fix by reverting this commit.

Cc: gushengxian <gushengxian@yulong.com>
Fixes: 9ea3e52c5bc8 ("flow_offload: action should not be NULL when it is referenced")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://lore.kernel.org/r/20210819105842.1315705-1-idosch@idosch.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 include/net/flow_offload.h | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/include/net/flow_offload.h b/include/net/flow_offload.h
index 161b90979038..123b1e9ea304 100644
--- a/include/net/flow_offload.h
+++ b/include/net/flow_offload.h
@@ -312,14 +312,12 @@ flow_action_mixed_hw_stats_check(const struct flow_action *action,
 	if (flow_offload_has_one_action(action))
 		return true;
 
-	if (action) {
-		flow_action_for_each(i, action_entry, action) {
-			if (i && action_entry->hw_stats != last_hw_stats) {
-				NL_SET_ERR_MSG_MOD(extack, "Mixing HW stats types for actions is not supported");
-				return false;
-			}
-			last_hw_stats = action_entry->hw_stats;
+	flow_action_for_each(i, action_entry, action) {
+		if (i && action_entry->hw_stats != last_hw_stats) {
+			NL_SET_ERR_MSG_MOD(extack, "Mixing HW stats types for actions is not supported");
+			return false;
 		}
+		last_hw_stats = action_entry->hw_stats;
 	}
 	return true;
 }
-- 
2.30.2