Messages in this thread | | | Date | Thu, 8 Mar 2012 12:06:17 -0800 | Subject | Re: [RFC] c/r: prctl: Add ability to set new mm_struct::exe_file v3 | From | Kees Cook <> |
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On Thu, Mar 8, 2012 at 12:02 PM, Andy Lutomirski <luto@amacapital.net> wrote: > On Thu, Mar 8, 2012 at 11:40 AM, Cyrill Gorcunov <gorcunov@openvz.org> wrote: >> On Thu, Mar 08, 2012 at 11:31:58AM -0800, Kees Cook wrote: >> ... >>> > + err = -EACCES; >>> > + if (!S_ISREG(dentry->d_inode->i_mode) || >>> > + exe_file->f_path.mnt->mnt_flags & MNT_NOEXEC) >>> > + goto exit; >>> >>> I'm starting to notice that this pattern (testing ISREG and >>> MNT_NOEXEC) is getting repeated a few times in the kernel, and at >>> least the no-new-privs patch (not yet in -mm but hopefully soon given >>> the seccomp_filter work) updates this pattern everywhere. Perhaps this >>> should be extracted into a helper first, and then this patch can call >>> that helper here? (And then nnp can just update the single helper.) >>> >> >> I can do that if Andrew agree. > > I'm a bit lost. nnp updates the MNT_NOSUID checks, not the MNT_NOEXEC > checks. (And the effects of the two flags is different in selinux for > historical reasons.) I'm sure I'm missing something.
Oops, you're right. Regardless, we might want helpers anyway. Better to have single places to do these tests.
-Kees
-- Kees Cook ChromeOS Security -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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