[Patch] kexec_load: check CAP_SYS_MODULE

[Amerigo Wang]

Eric pointed out that kexec_load() actually allows you to
run any code you want in ring0, this is more like CAP_SYS_MODULE.

Reported-by: Eric Paris <eparis at redhat.com>
Signed-off-by: WANG Cong <amwang at redhat.com>

---
diff --git a/kernel/kexec.c b/kernel/kexec.c
index b55045b..c30d613 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -945,7 +945,7 @@ SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments,
 	int result;
 
 	/* We only trust the superuser with rebooting the system. */
-	if (!capable(CAP_SYS_BOOT))
+	if (!capable(CAP_SYS_BOOT) || !capable(CAP_SYS_MODULE))
 		return -EPERM;
 
 	/*