[PATCH] close mprotect noexec hole

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



The following patch closes the hole in mprotect discovered during
the noexec mount discussions.  Without this the protection is
incomplete and pretty much useless.  With it and additional techniques
like SELinux all holes can be plugged in a fine-grained way.

I think it should be in .19 since it's a security problem not to have
it.  Tested on x86-64.


Signed-off-by: Ulrich Drepper <[email protected]>

--- mm/mprotect.c	2006-10-01 09:35:14.000000000 -0700
+++ mm/mprotect.c-new	2006-10-11 14:54:55.000000000 -0700
@@ -251,6 +251,10 @@
 	error = -ENOMEM;
 	if (!vma)
 		goto out;
+	error = -EACCES;
+	if ((reqprot & PROT_EXEC) && vma->vm_file &&
+	    (vma->vm_file->f_vfsmnt->mnt_flags & MNT_NOEXEC))
+		goto out;
 	if (unlikely(grows & PROT_GROWSDOWN)) {
 		if (vma->vm_start >= end)
 			goto out;
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

[Index of Archives]     [Kernel Newbies]     [Netfilter]     [Bugtraq]     [Photo]     [Stuff]     [Gimp]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Video 4 Linux]     [Linux for the blind]     [Linux Resources]
  Powered by Linux