linux-kernel - [PATCH] cxl: core: Initialize eiw and eig to fix potential uninitialized use

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-Id: <20250419203530.45594-1-purvayeshi550@gmail.com>
Date: Sun, 20 Apr 2025 02:05:30 +0530
From: Purva Yeshi <purvayeshi550@...il.com>
To: dave@...olabs.net,
	jonathan.cameron@...wei.com,
	dave.jiang@...el.com,
	alison.schofield@...el.com,
	vishal.l.verma@...el.com,
	ira.weiny@...el.com,
	dan.j.williams@...el.com
Cc: ming.li@...omail.com,
	huang.ying.caritas@...il.com,
	linux-cxl@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Purva Yeshi <purvayeshi550@...il.com>
Subject: [PATCH] cxl: core: Initialize eiw and eig to fix potential uninitialized use

Fix Smatch-detected issue:

drivers/cxl/core/region.c:1292 check_interleave_cap()
error: uninitialized symbol 'eiw'.
drivers/cxl/core/region.c:1297 check_interleave_cap()
error: uninitialized symbol 'eig'.
drivers/cxl/core/region.c:1299 check_interleave_cap()
error: uninitialized symbol 'eig'.

Smatch reports possible uninitialized usage of these variables if
the helper functions ways_to_eiw() or granularity_to_eig() fail to
assign values under certain conditions.

Initialize the eiw and eig variables to zero when they are declared
in check_interleave_cap() to prevent potential use of uninitialized
values.

Signed-off-by: Purva Yeshi <purvayeshi550@...il.com>
---
 drivers/cxl/core/region.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
index c3f4dc244df7..edf8636f190a 100644
--- a/drivers/cxl/core/region.c
+++ b/drivers/cxl/core/region.c
@@ -1266,8 +1266,8 @@ static int check_interleave_cap(struct cxl_decoder *cxld, int iw, int ig)
 	struct cxl_port *port = to_cxl_port(cxld->dev.parent);
 	struct cxl_hdm *cxlhdm = dev_get_drvdata(&port->dev);
 	unsigned int interleave_mask;
-	u8 eiw;
-	u16 eig;
+	u8 eiw = 0;
+	u16 eig = 0;
 	int high_pos, low_pos;

 	if (!test_bit(iw, &cxlhdm->iw_cap_mask))
-- 
2.34.1