powerpc/pseries/lparcfg: Fix possible overflow are more than 1026
need set '\0' for 'local_buffer'.
SPLPAR_MAXLENGTH is 1026, RTAS_DATA_BUF_SIZE is 4096. so the contents of
rtas_data_buf may truncated in memcpy.
if contents are really truncated.
the splpar_strlen is more than 1026. the next while loop checking will
not find the end of buffer. that will cause memory access violation.
Signed-off-by: Chen Gang <gang.chen@asianux.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/kernel/lparcfg.c b/arch/powerpc/kernel/lparcfg.c
index f5725bc..ab297f4 100644
--- a/arch/powerpc/kernel/lparcfg.c
+++ b/arch/powerpc/kernel/lparcfg.c
@@ -301,6 +301,7 @@
__pa(rtas_data_buf),
RTAS_DATA_BUF_SIZE);
memcpy(local_buffer, rtas_data_buf, SPLPAR_MAXLENGTH);
+ local_buffer[SPLPAR_MAXLENGTH - 1] = '\0';
spin_unlock(&rtas_data_buf_lock);
if (call_status != 0) {