Re: [Patch] kexec_load: check CAP_SYS_MODULE

From: Cong Wang
Date: Thu Jan 06 2011 - 03:27:25 EST


(Forgot Cc'ing Eric Paris, adding.)

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@xxxxxxxxxx>
Signed-off-by: WANG Cong<amwang@xxxxxxxxxx>

---
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;

/*

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