Patch "leds: trigger: ledtrig-cpu:: Fix 'output may be truncated' issue for 'cpu'" has been added to the 5.4-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

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

    leds: trigger: ledtrig-cpu:: Fix 'output may be truncated' issue for 'cpu'

to the 5.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     leds-trigger-ledtrig-cpu-fix-output-may-be-truncated.patch
and it can be found in the queue-5.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 668a54f60cd9a2fb5f253c79c59774f670c6626e
Author: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
Date:   Sat Sep 23 09:15:38 2023 +0200

    leds: trigger: ledtrig-cpu:: Fix 'output may be truncated' issue for 'cpu'
    
    [ Upstream commit ff50f53276131a3059e8307d11293af388ed2bcd ]
    
    In order to teach the compiler that 'trig->name' will never be truncated,
    we need to tell it that 'cpu' is not negative.
    
    When building with W=1, this fixes the following warnings:
    
      drivers/leds/trigger/ledtrig-cpu.c: In function ‘ledtrig_cpu_init’:
      drivers/leds/trigger/ledtrig-cpu.c:155:56: error: ‘%d’ directive output may be truncated writing between 1 and 11 bytes into a region of size 5 [-Werror=format-truncation=]
        155 |                 snprintf(trig->name, MAX_NAME_LEN, "cpu%d", cpu);
            |                                                        ^~
      drivers/leds/trigger/ledtrig-cpu.c:155:52: note: directive argument in the range [-2147483648, 7]
        155 |                 snprintf(trig->name, MAX_NAME_LEN, "cpu%d", cpu);
            |                                                    ^~~~~~~
      drivers/leds/trigger/ledtrig-cpu.c:155:17: note: ‘snprintf’ output between 5 and 15 bytes into a destination of size 8
        155 |                 snprintf(trig->name, MAX_NAME_LEN, "cpu%d", cpu);
            |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    
    Fixes: 8f88731d052d ("led-triggers: create a trigger for CPU activity")
    Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
    Link: https://lore.kernel.org/r/3f4be7a99933cf8566e630da54f6ab913caac432.1695453322.git.christophe.jaillet@xxxxxxxxxx
    Signed-off-by: Lee Jones <lee@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/leds/trigger/ledtrig-cpu.c b/drivers/leds/trigger/ledtrig-cpu.c
index fca62d5035909..f19baed615023 100644
--- a/drivers/leds/trigger/ledtrig-cpu.c
+++ b/drivers/leds/trigger/ledtrig-cpu.c
@@ -130,7 +130,7 @@ static int ledtrig_prepare_down_cpu(unsigned int cpu)
 
 static int __init ledtrig_cpu_init(void)
 {
-	int cpu;
+	unsigned int cpu;
 	int ret;
 
 	/* Supports up to 9999 cpu cores */
@@ -152,7 +152,7 @@ static int __init ledtrig_cpu_init(void)
 		if (cpu >= 8)
 			continue;
 
-		snprintf(trig->name, MAX_NAME_LEN, "cpu%d", cpu);
+		snprintf(trig->name, MAX_NAME_LEN, "cpu%u", cpu);
 
 		led_trigger_register_simple(trig->name, &trig->_trig);
 	}