components: libc: fix array overflow in rt_object name assignment
[Problem Description]
When assigning name to rt_object, strncpy() uses size equal to RT_NAME_MAX,
which causes missing null-terminator and overflows into adjacent 'type' field.
This corruption leads to unexpected system behavior.
[Problem Analysis]
The rt_object structure defines:
| char name[RT_NAME_MAX] | -> buffer
| rt_uint8_t type | -> adjacent field
Original code calculates size as:
size = end - first + 1;
if (size > RT_NAME_MAX) size = RT_NAME_MAX;
When size equals RT_NAME_MAX, strncpy() will copy exactly RT_NAME_MAX bytes
without adding terminating '\0', causing two issues:
1. name buffer is not null-terminated
2. The implicit null-byte writes beyond name[] into type field
[Solution]
Change boundary check from:
if (size > RT_NAME_MAX) size = RT_NAME_MAX;
to:
if (size >= RT_NAME_MAX) size = RT_NAME_MAX - 1;
This ensures:
1. Always leaves space for null-terminator
2. Prevents overflow into type field
3. Maintains maximum valid name length (RT_NAME_MAX-1 + '\0')
Signed-off-by: Liu Gui <kenneth.liu@sophgo.com>