patch "iio: frequency: admv1013: fix NULL pointer dereference on str" added to char-misc-next

patch "iio: frequency: admv1013: fix NULL pointer dereference on str" added to char-misc-next

[gregkh]

This is a note to let you know that I've just added the patch titled

    iio: frequency: admv1013: fix NULL pointer dereference on str

to my char-misc git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git
in the char-misc-next branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will also be merged in the next major kernel release
during the merge window.

If you have any questions about this process, please let me know.


From aac0a51b16700b403a55b67ba495de021db78763 Mon Sep 17 00:00:00 2001
From: Antoniu Miclaus <antoniu.miclaus@analog.com>
Date: Thu, 5 Mar 2026 11:14:48 +0200
Subject: iio: frequency: admv1013: fix NULL pointer dereference on str
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

When device_property_read_string() fails, str is left uninitialized
but the code falls through to strcmp(str, ...), dereferencing a garbage
pointer. Replace manual read/strcmp with
device_property_match_property_string() and consolidate the SE mode
enums into a single sequential enum, mapping to hardware register
values via a switch consistent with other bitfields in the driver.

Several cleanup patches have been applied to this driver recently so
this will need a manual backport.

Fixes: da35a7b526d9 ("iio: frequency: admv1013: add support for ADMV1013")
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---
 drivers/iio/frequency/admv1013.c | 65 ++++++++++++++++++--------------
 1 file changed, 37 insertions(+), 28 deletions(-)

diff --git a/drivers/iio/frequency/admv1013.c b/drivers/iio/frequency/admv1013.c
index 9202443ef445..b852378b3f68 100644
--- a/drivers/iio/frequency/admv1013.c
+++ b/drivers/iio/frequency/admv1013.c
@@ -85,9 +85,9 @@ enum {
 };
 
 enum {
-	ADMV1013_SE_MODE_POS = 6,
-	ADMV1013_SE_MODE_NEG = 9,
-	ADMV1013_SE_MODE_DIFF = 12
+	ADMV1013_SE_MODE_POS,
+	ADMV1013_SE_MODE_NEG,
+	ADMV1013_SE_MODE_DIFF,
 };
 
 struct admv1013_state {
@@ -468,10 +468,23 @@ static int admv1013_init(struct admv1013_state *st, int vcm_uv)
 	if (ret)
 		return ret;
 
-	data = FIELD_PREP(ADMV1013_QUAD_SE_MODE_MSK, st->quad_se_mode);
+	switch (st->quad_se_mode) {
+	case ADMV1013_SE_MODE_POS:
+		data = 6;
+		break;
+	case ADMV1013_SE_MODE_NEG:
+		data = 9;
+		break;
+	case ADMV1013_SE_MODE_DIFF:
+		data = 12;
+		break;
+	default:
+		return -EINVAL;
+	}
 
 	ret = __admv1013_spi_update_bits(st, ADMV1013_REG_QUAD,
-					 ADMV1013_QUAD_SE_MODE_MSK, data);
+					 ADMV1013_QUAD_SE_MODE_MSK,
+					 FIELD_PREP(ADMV1013_QUAD_SE_MODE_MSK, data));
 	if (ret)
 		return ret;
 
@@ -512,37 +525,33 @@ static void admv1013_powerdown(void *data)
 	admv1013_spi_update_bits(data, ADMV1013_REG_ENABLE, enable_reg_msk, enable_reg);
 }
 
+static const char * const admv1013_input_modes[] = {
+	[ADMV1013_IQ_MODE] = "iq",
+	[ADMV1013_IF_MODE] = "if",
+};
+
+static const char * const admv1013_quad_se_modes[] = {
+	[ADMV1013_SE_MODE_POS] = "se-pos",
+	[ADMV1013_SE_MODE_NEG] = "se-neg",
+	[ADMV1013_SE_MODE_DIFF] = "diff",
+};
+
 static int admv1013_properties_parse(struct admv1013_state *st)
 {
 	int ret;
-	const char *str;
 	struct device *dev = &st->spi->dev;
 
 	st->det_en = device_property_read_bool(dev, "adi,detector-enable");
 
-	ret = device_property_read_string(dev, "adi,input-mode", &str);
-	if (ret)
-		st->input_mode = ADMV1013_IQ_MODE;
+	ret = device_property_match_property_string(dev, "adi,input-mode",
+						    admv1013_input_modes,
+						    ARRAY_SIZE(admv1013_input_modes));
+	st->input_mode = ret >= 0 ? ret : ADMV1013_IQ_MODE;
 
-	if (!strcmp(str, "iq"))
-		st->input_mode = ADMV1013_IQ_MODE;
-	else if (!strcmp(str, "if"))
-		st->input_mode = ADMV1013_IF_MODE;
-	else
-		return -EINVAL;
-
-	ret = device_property_read_string(dev, "adi,quad-se-mode", &str);
-	if (ret)
-		st->quad_se_mode = ADMV1013_SE_MODE_DIFF;
-
-	if (!strcmp(str, "diff"))
-		st->quad_se_mode = ADMV1013_SE_MODE_DIFF;
-	else if (!strcmp(str, "se-pos"))
-		st->quad_se_mode = ADMV1013_SE_MODE_POS;
-	else if (!strcmp(str, "se-neg"))
-		st->quad_se_mode = ADMV1013_SE_MODE_NEG;
-	else
-		return -EINVAL;
+	ret = device_property_match_property_string(dev, "adi,quad-se-mode",
+						    admv1013_quad_se_modes,
+						    ARRAY_SIZE(admv1013_quad_se_modes));
+	st->quad_se_mode = ret >= 0 ? ret : ADMV1013_SE_MODE_DIFF;
 
 	ret = devm_regulator_bulk_get_enable(dev,
 					     ARRAY_SIZE(admv1013_vcc_regs),
-- 
2.53.0