From: Wolfram Sang <wsa+renesas@sang-engineering.com>
To: linux-renesas-soc@vger.kernel.org
Cc: Wolfram Sang <wsa+renesas@sang-engineering.com>,
Baruch Siach <baruch@tkos.co.il>,
linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] i2c: smbus: fix NULL function pointer dereference
Date: Fri, 26 Apr 2024 08:44:08 +0200 [thread overview]
Message-ID: <20240426064408.7372-1-wsa+renesas@sang-engineering.com> (raw)
Brauch reported an OOPS when using the designware controller as target
only. Target-only modes break the assumption of one transfer function
always being available. Fix this by always checking the pointer in
__i2c_transfer.
Reported-by: Baruch Siach <baruch@tkos.co.il>
Closes: https://lore.kernel.org/r/4269631780e5ba789cf1ae391eec1b959def7d99.1712761976.git.baruch@tkos.co.il
Fixes: 4b1acc43331d ("i2c: core changes for slave support")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
---
drivers/i2c/i2c-core-base.c | 12 ++++++------
drivers/i2c/i2c-core-smbus.c | 2 +-
2 files changed, 7 insertions(+), 7 deletions(-)
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index ff5c486a1dbb..db0d1ac82910 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -2200,13 +2200,18 @@ static int i2c_check_for_quirks(struct i2c_adapter *adap, struct i2c_msg *msgs,
* Returns negative errno, else the number of messages executed.
*
* Adapter lock must be held when calling this function. No debug logging
- * takes place. adap->algo->master_xfer existence isn't checked.
+ * takes place.
*/
int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
{
unsigned long orig_jiffies;
int ret, try;
+ if (!adap->algo->master_xfer) {
+ dev_dbg(&adap->dev, "I2C level transfers not supported\n");
+ return -EOPNOTSUPP;
+ }
+
if (WARN_ON(!msgs || num < 1))
return -EINVAL;
@@ -2273,11 +2278,6 @@ int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
{
int ret;
- if (!adap->algo->master_xfer) {
- dev_dbg(&adap->dev, "I2C level transfers not supported\n");
- return -EOPNOTSUPP;
- }
-
/* REVISIT the fault reporting model here is weak:
*
* - When we get an error after receiving N bytes from a slave,
diff --git a/drivers/i2c/i2c-core-smbus.c b/drivers/i2c/i2c-core-smbus.c
index e3b96fc53b5c..a942c5306a4e 100644
--- a/drivers/i2c/i2c-core-smbus.c
+++ b/drivers/i2c/i2c-core-smbus.c
@@ -596,7 +596,7 @@ s32 __i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
break;
}
- if (res != -EOPNOTSUPP || !adapter->algo->master_xfer)
+ if (res != -EOPNOTSUPP)
goto trace;
/*
* Fall back to i2c_smbus_xfer_emulated if the adapter doesn't
--
2.39.2
next reply other threads:[~2024-04-26 6:44 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-04-26 6:44 Wolfram Sang [this message]
2024-04-26 7:28 ` [PATCH] i2c: smbus: fix NULL function pointer dereference Sergei Shtylyov
2024-04-26 8:39 ` Wolfram Sang
2024-04-26 8:32 ` Baruch Siach
2024-04-26 9:52 ` Wolfram Sang
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20240426064408.7372-1-wsa+renesas@sang-engineering.com \
--to=wsa+renesas@sang-engineering.com \
--cc=baruch@tkos.co.il \
--cc=linux-i2c@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-renesas-soc@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).