6a91557e4c
Do a couple things here: - Split the mega-patches into individual patches. Should help with rebasing. - Make all patches 'git am' acceptable. There should be no functional or actual code differences from before
44 lines
1.2 KiB
Diff
44 lines
1.2 KiB
Diff
From 81f5d112eeb6998c51c7c0410bf277bf49e66a8a Mon Sep 17 00:00:00 2001
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From: Matthew Garrett <matthew.garrett@nebula.com>
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Date: Fri, 8 Feb 2013 11:12:13 -0800
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Subject: [PATCH] x86: Restrict MSR access when module loading is restricted
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Writing to MSRs should not be allowed if module loading is restricted,
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since it could lead to execution of arbitrary code in kernel mode. Based
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on a patch by Kees Cook.
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Cc: Kees Cook <keescook@chromium.org>
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Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>
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---
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arch/x86/kernel/msr.c | 7 +++++++
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1 file changed, 7 insertions(+)
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diff --git a/arch/x86/kernel/msr.c b/arch/x86/kernel/msr.c
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index c9603ac80de5..8bef43fc3f40 100644
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--- a/arch/x86/kernel/msr.c
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+++ b/arch/x86/kernel/msr.c
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@@ -103,6 +103,9 @@ static ssize_t msr_write(struct file *file, const char __user *buf,
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int err = 0;
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ssize_t bytes = 0;
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+ if (secure_modules())
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+ return -EPERM;
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+
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if (count % 8)
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return -EINVAL; /* Invalid chunk size */
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@@ -150,6 +153,10 @@ static long msr_ioctl(struct file *file, unsigned int ioc, unsigned long arg)
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err = -EBADF;
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break;
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}
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+ if (secure_modules()) {
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+ err = -EPERM;
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+ break;
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+ }
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if (copy_from_user(®s, uregs, sizeof regs)) {
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err = -EFAULT;
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break;
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--
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1.9.3
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