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| author | Wolfram Sang <wsa+renesas@sang-engineering.com> | 2024-04-26 09:44:08 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-05-02 17:23:45 +0300 |
| commit | 5fd72404587d7db4acb2d241fd8c387afb0a7aec (patch) | |
| tree | 929a074a5554bcbf9a03c200e3d2f02243dfc971 | |
| parent | 04bf2e5f95c1a52e28a7567a507f926efe31c3b6 (diff) | |
| download | linux-5fd72404587d7db4acb2d241fd8c387afb0a7aec.tar.xz | |
i2c: smbus: fix NULL function pointer dereference
[ Upstream commit 91811a31b68d3765b3065f4bb6d7d6d84a7cfc9f ]
Baruch 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")
[wsa: dropped the simplification in core-smbus to avoid theoretical regressions]
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Tested-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/i2c/i2c-core-base.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index 34fecf97a355..e8a89e18c640 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -2013,13 +2013,18 @@ 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; @@ -2086,11 +2091,6 @@ 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, |