linux-kernel - [PATCH] i2c: Remove redundant comparison in npcm_i2c_reg

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Date: Tue,  6 Feb 2024 22:42:01 +0300
From: Rand Deeb <rand.sec96@...il.com>
To: Avi Fishman <avifishman70@...il.com>,
	Tomer Maimon <tmaimon77@...il.com>,
	Tali Perry <tali.perry1@...il.com>,
	Patrick Venture <venture@...gle.com>,
	Nancy Yuen <yuenn@...gle.com>,
	Benjamin Fair <benjaminfair@...gle.com>,
	openbmc@...ts.ozlabs.org,
	linux-i2c@...r.kernel.org,
	linux-kernel@...r.kernel.org
Cc: deeb.rand@...fident.ru,
	lvc-project@...uxtesting.org,
	voskresenski.stanislav@...fident.ru,
	Rand Deeb <rand.sec96@...il.com>
Subject: [PATCH] i2c: Remove redundant comparison in npcm_i2c_reg_slave

In the npcm_i2c_reg_slave() function, there was a redundant
comparison that checked if 'bus->slave' was null immediately after
assigning it the 'client' value. There were concerns about a
potential null dereference because of `client->adapter`, but
according to Wolfram Sang, "we trusted ourselves here" Therefore,
this comparison is unnecessary.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Signed-off-by: Rand Deeb <rand.sec96@...il.com>
---
 drivers/i2c/busses/i2c-npcm7xx.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index c1b679737240..bdf35b86e559 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -1247,9 +1247,6 @@ static int npcm_i2c_reg_slave(struct i2c_client *client)
 
 	bus->slave = client;
 
-	if (!bus->slave)
-		return -EINVAL;
-
 	if (client->flags & I2C_CLIENT_TEN)
 		return -EAFNOSUPPORT;
 
-- 
2.34.1