From 7aeef1548ac026c8bcb9ec223b672f81da340011 Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Mon, 8 Aug 2022 02:48:21 -0700 Subject: [PATCH] hwmon: (lm90) Fix error return value from detect function MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit lm90_detect_nuvoton() is supposed to return NULL if it can not detect a chip, or a pointer to the chip name if it does. Under some circumstances it returns an error pointer instead. Some versions of gcc interpret an ERR_PTR as region of size 0 and generate an error message. In function ‘__fortify_strlen’, inlined from ‘strlcpy’ at ./include/linux/fortify-string.h:159:10, inlined from ‘lm90_detect’ at drivers/hwmon/lm90.c:2550:2: ./include/linux/fortify-string.h:50:33: error: ‘__builtin_strlen’ reading 1 or more bytes from a region of size 0 50 | #define __underlying_strlen __builtin_strlen | ^ ./include/linux/fortify-string.h:141:24: note: in expansion of macro ‘__underlying_strlen’ 141 | return __underlying_strlen(p); | ^~~~~~~~~~~~~~~~~~~ Returning NULL instead of ERR_PTR() fixes the problem. Fixes: c7cebce984a2 ("hwmon: (lm90) Rework detect function") Reported-by: Ingo Molnar Cc: Linus Torvalds Cc: Kees Cook Tested-by: Ingo Molnar Reviewed-by: Kees Cook Signed-off-by: Guenter Roeck --- drivers/hwmon/lm90.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/hwmon/lm90.c b/drivers/hwmon/lm90.c index 03d07da..221de01 100644 --- a/drivers/hwmon/lm90.c +++ b/drivers/hwmon/lm90.c @@ -2321,7 +2321,7 @@ static const char *lm90_detect_nuvoton(struct i2c_client *client, int chip_id, const char *name = NULL; if (config2 < 0) - return ERR_PTR(-ENODEV); + return NULL; if (address == 0x4c && !(config1 & 0x2a) && !(config2 & 0xf8)) { if (chip_id == 0x01 && convrate <= 0x09) { -- 2.7.4