[PATCH] led-class-flash: fix -Wrestrict warning

From: Arnd Bergmann
Date: Mon Sep 27 2021 - 06:16:18 EST


From: Arnd Bergmann <arnd@xxxxxxxx>

drivers/leds/led-class-flash.c: In function 'flash_fault_show':
drivers/leds/led-class-flash.c:210:16: error: 'sprintf' argument 3 overlaps destination object 'buf' [-Werror=restrict]
210 | return sprintf(buf, "%s\n", buf);
| ^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/leds/led-class-flash.c:187:54: note: destination object referenced by 'restrict'-qualified argument 1 was declared here
187 | struct device_attribute *attr, char *buf)
| ~~~~~~^~~
cc1: all warnings being treated as errors
make[5]: *** [scripts/Makefile.build:277: drivers/leds/led-class-flash.o] Error 1
make[5]: Target '__build' not remade because of errors.
make[4]: *** [scripts/Makefile.build:540: drivers/leds] Error 2
drivers/thunderbolt/xdomain.c: In function 'modalias_show':
drivers/thunderbolt/xdomain.c:733:16: error: 'sprintf' argument 3 overlaps destination object 'buf' [-Werror=restrict]
733 | return sprintf(buf, "%s\n", buf);
| ^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/thunderbolt/xdomain.c:727:36: note: destination object referenced by 'restrict'-qualified argument 1 was declared here
727 | char *buf)
| ~~~~~~^~~

Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
drivers/leds/led-class-flash.c | 2 +-
drivers/thunderbolt/xdomain.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/leds/led-class-flash.c b/drivers/leds/led-class-flash.c
index 185e17055317..6fe9d700dfef 100644
--- a/drivers/leds/led-class-flash.c
+++ b/drivers/leds/led-class-flash.c
@@ -207,7 +207,7 @@ static ssize_t flash_fault_show(struct device *dev,
mask <<= 1;
}

- return sprintf(buf, "%s\n", buf);
+ return strlen(strcat(buf, "\n"));
}
static DEVICE_ATTR_RO(flash_fault);

diff --git a/drivers/thunderbolt/xdomain.c b/drivers/thunderbolt/xdomain.c
index d66ea4d616fd..eff32499610f 100644
--- a/drivers/thunderbolt/xdomain.c
+++ b/drivers/thunderbolt/xdomain.c
@@ -730,7 +730,7 @@ static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,

/* Full buffer size except new line and null termination */
get_modalias(svc, buf, PAGE_SIZE - 2);
- return sprintf(buf, "%s\n", buf);
+ return strlen(strcat(buf, "\n"));
}
static DEVICE_ATTR_RO(modalias);

--
2.29.2