From: Armin Wolf W_Armin@gmx.de
[ Upstream commit f2ac14b5f197e4a2dec51e5ceaa56682ff1592bc ]
When encountering a string bigger than the destination buffer (32 bytes), the string is not properly NUL-terminated, causing buffer overreads later.
This for example happens on the Inspiron 3505, where the battery model name is larger than 32 bytes, which leads to sysfs showing the model name together with the serial number string (which is NUL-terminated and thus prevents worse).
Fix this by using strscpy() which ensures that the result is always NUL-terminated.
Fixes: 106449e870b3 ("ACPI: Battery: Allow extract string from integer") Signed-off-by: Armin Wolf W_Armin@gmx.de Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/acpi/battery.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c index 974c2df13da1d..a49a09e3de1b3 100644 --- a/drivers/acpi/battery.c +++ b/drivers/acpi/battery.c @@ -465,7 +465,7 @@ static int extract_package(struct acpi_battery *battery, u8 *ptr = (u8 *)battery + offsets[i].offset; if (element->type == ACPI_TYPE_STRING || element->type == ACPI_TYPE_BUFFER) - strncpy(ptr, element->string.pointer, 32); + strscpy(ptr, element->string.pointer, 32); else if (element->type == ACPI_TYPE_INTEGER) { strncpy(ptr, (u8 *)&element->integer.value, sizeof(u64));