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From: Amerigo Wang <amwang@redhat.com>
To: linux-kernel@vger.kernel.org
Cc: WANG Cong <amwang@redhat.com>,
	Eric Biederman <ebiederm@xmission.com>,
	kexec@lists.infradead.org
Subject: [Patch] kexec_load: check CAP_SYS_MODULE
Date: Thu,  6 Jan 2011 16:25:25 +0800	[thread overview]
Message-ID: <1294302325-22593-1-git-send-email-amwang@redhat.com> (raw)

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@redhat.com>
Signed-off-by: WANG Cong <amwang@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;
 
 	/*

             reply	other threads:[~2011-01-06  8:25 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-01-06  8:25 Amerigo Wang [this message]
2011-01-06  8:27 ` [Patch] kexec_load: check CAP_SYS_MODULE Cong Wang
2011-01-06  8:47 ` Eric W. Biederman
2011-01-06 19:02   ` Eric Paris
2011-01-07 20:10     ` Eric W. Biederman
2011-01-07 20:32       ` Eric Paris
2011-01-07 21:02         ` Eric W. Biederman
2011-01-08  0:39           ` Eric Paris
2011-01-09  2:09             ` Eric W. Biederman
2011-01-11 11:26               ` Cong Wang
2011-01-14 19:47               ` Eric Paris

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