ACPICA: Switch back to using strncpy() in acpi_ut_safe_strncpy()

ACPICA commit b90d0d65ec97ff8279ad826f4102e0d31c5f662a

I mistakenly replaced strncpy() with memcpy() in commit ebf27765421c
("ACPICA: Replace strncpy() with memcpy()"), not realizing the entire
context behind *why* strncpy() was used.

In this safer implementation of strncpy(), it does not make
sense to use memcpy() only to null-terminate strings passed to
acpi_ut_safe_strncpy() one byte early.

The consequences of doing so are understandably *bad*, as was
evident by the kernel test bot reporting problems [1].

Fixes: ebf27765421c ("ACPICA: Replace strncpy() with memcpy()")
Link: https://lore.kernel.org/all/202505081033.50e45ff4-lkp@intel.com
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202505081033.50e45ff4-lkp@intel.com
Link: https://github.com/acpica/acpica/commit/b90d0d65
Signed-off-by: Ahmed Salem <x0rw3ll@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/12685690.O9o76ZdvQC@rjwysocki.net

diff --git a/drivers/acpi/acpica/utnonansi.c b/drivers/acpi/acpica/utnonansi.c
index 803e3e8938251ea4b7cb0a1401ac8b2b5fc0a144..ff0802ace19b72add24d43a2eb14b98eed920337 100644 (file)
--- a/drivers/acpi/acpica/utnonansi.c
+++ b/drivers/acpi/acpica/utnonansi.c
@@ -168,7 +168,7 @@ void acpi_ut_safe_strncpy(char *dest, char *source, acpi_size dest_size)
 {
        /* Always terminate destination string */
 
-       memcpy(dest, source, dest_size);
+       strncpy(dest, source, dest_size);
        dest[dest_size - 1] = 0;
 }