[PATCH] ACPICA: Fix sprintf() INT_MAX -Wformat-truncation= warn

From: Shuah Khan
Date: Wed Nov 16 2022 - 10:23:15 EST


utprint module is included in tools/acpidump and when acpidump is built,
the following warning occurs.

CC tools/acpidump/utprint.o
/usr/include/x86_64-linux-gnu/bits/stdio2.h: In function ‘sprintf’:
../../../../../drivers/acpi/acpica/utprint.c:602:18: warning: specified bound 4294901760 exceeds ‘INT_MAX’ [-Wformat-truncation=]
602 | length = vsnprintf(string, ACPI_UINT32_MAX-ACPI_UINT16_MAX,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
603 | format, args);
| ~~~~~~~~~~~~~

Fix sprintf() to use ACPI_UINT32_MAX/2 to get rid of the truncate problem.
This change is inline other sprintf() implementations.

If using ACPI_UINT32_MAX is necessary in the kernel, acpidump might require
special case to get rid of this truncate problem.

Signed-off-by: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>
---
drivers/acpi/acpica/utprint.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/acpi/acpica/utprint.c b/drivers/acpi/acpica/utprint.c
index d5aa2109847f..02cff16c8f77 100644
--- a/drivers/acpi/acpica/utprint.c
+++ b/drivers/acpi/acpica/utprint.c
@@ -599,7 +599,7 @@ int sprintf(char *string, const char *format, ...)
int length;

va_start(args, format);
- length = vsnprintf(string, ACPI_UINT32_MAX, format, args);
+ length = vsnprintf(string, ACPI_UINT32_MAX/2, format, args);
va_end(args);

return (length);
--
2.34.1