From: "Tobin C. Harding" <me@tobin.cc>
To: Greg KH <gregkh@linuxfoundation.org>,
Petr Mladek <pmladek@suse.com>, Joe Perches <joe@perches.com>,
Ian Campbell <ijc@hellion.org.uk>,
Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: "Tobin C. Harding" <me@tobin.cc>,
kernel-hardening@lists.openwall.com,
linux-kernel@vger.kernel.org,
Catalin Marinas <catalin.marinas@arm.com>,
Will Deacon <will.deacon@arm.com>,
Steven Rostedt <rostedt@goodmis.org>,
William Roberts <william.c.roberts@intel.com>,
Chris Fries <cfries@google.com>,
Dave Weinstein <olorin@google.com>
Subject: [kernel-hardening] [RFC V2 4/6] lib: vsprintf: default kptr_restrict to the maximum value
Date: Sun, 1 Oct 2017 11:06:48 +1100 [thread overview]
Message-ID: <1506816410-10230-5-git-send-email-me@tobin.cc> (raw)
In-Reply-To: <1506816410-10230-1-git-send-email-me@tobin.cc>
Set the initial value of kptr_restrict to the maximum
setting rather than the minimum setting, to ensure that
early boot logging is not leaking information.
Signed-off-by: Tobin C. Harding <me@tobin.cc>
---
lib/vsprintf.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 0271223..e009325 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -396,7 +396,7 @@ struct printf_spec {
#define FIELD_WIDTH_MAX ((1 << 23) - 1)
#define PRECISION_MAX ((1 << 15) - 1)
-int kptr_restrict __read_mostly;
+int kptr_restrict __read_mostly = 4; /* maximum setting */
/*
* return non-zero if we should cleanse pointers for %p and %pK specifiers.
--
2.7.4
next prev parent reply other threads:[~2017-10-01 0:06 UTC|newest]
Thread overview: 68+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-10-01 0:06 [kernel-hardening] [RFC V2 0/6] add more kernel pointer filter options Tobin C. Harding
2017-10-01 0:06 ` [kernel-hardening] [RFC V2 1/6] lib: vsprintf: additional kernel pointer filtering options Tobin C. Harding
2017-10-04 8:55 ` Greg KH
2017-10-04 13:08 ` Steven Rostedt
2017-10-04 13:26 ` Greg KH
2017-10-04 13:29 ` Steven Rostedt
2017-10-04 13:54 ` Greg KH
2017-10-01 0:06 ` [kernel-hardening] [RFC V2 2/6] lib: vsprintf: whitelist stack traces Tobin C. Harding
2017-10-02 10:42 ` Will Deacon
2017-10-02 21:49 ` Tobin C. Harding
2017-10-04 8:56 ` Greg KH
2017-10-04 8:58 ` Will Deacon
2017-10-04 9:02 ` Greg KH
2017-10-04 10:42 ` Tobin C. Harding
2017-10-01 0:06 ` [kernel-hardening] [RFC V2 3/6] lib: vsprintf: physical address kernel pointer filtering options Tobin C. Harding
2017-10-04 8:58 ` Greg KH
2017-10-01 0:06 ` Tobin C. Harding [this message]
2017-10-04 8:55 ` [kernel-hardening] [RFC V2 4/6] lib: vsprintf: default kptr_restrict to the maximum value Greg KH
2017-10-04 16:42 ` Kees Cook
2017-10-04 16:48 ` Roberts, William C
2017-10-04 17:08 ` Linus Torvalds
2017-10-04 17:28 ` Linus Torvalds
2017-10-04 19:13 ` Jann Horn
2017-10-04 19:23 ` Linus Torvalds
2017-10-01 0:06 ` [kernel-hardening] [RFC V2 5/6] lib: vsprintf: add "%paP", "%papP", and "%padP" specifiers Tobin C. Harding
2017-10-04 8:58 ` Greg KH
2017-10-01 0:06 ` [kernel-hardening] [RFC V2 6/6] drivers: uio: un-restrict sysfs pointers for UIO Tobin C. Harding
2017-10-04 8:58 ` Greg KH
2017-10-01 0:11 ` [kernel-hardening] [RFC V2 0/6] add more kernel pointer filter options Tobin C. Harding
2017-10-04 8:57 ` Greg KH
2017-10-04 10:45 ` Tobin C. Harding
2017-10-04 8:58 ` Greg KH
2017-10-04 10:50 ` Tobin C. Harding
2017-10-04 12:42 ` Greg KH
2017-10-04 13:28 ` Steven Rostedt
2017-10-04 13:31 ` Steven Rostedt
2017-10-04 16:17 ` Roberts, William C
2017-10-04 15:41 ` Linus Torvalds
2017-10-04 16:22 ` Boris Lukashev
2017-10-04 16:29 ` Linus Torvalds
2017-10-04 16:54 ` Steven Rostedt
2017-10-04 18:58 ` Jordan Glover
2017-10-04 19:19 ` Linus Torvalds
2017-10-04 21:58 ` Roberts, William C
2017-10-04 23:21 ` Daniel Micay
2017-10-04 23:52 ` Linus Torvalds
2017-10-05 0:09 ` Linus Torvalds
2017-10-05 13:55 ` Bjorn Helgaas
2017-10-05 0:29 ` Daniel Micay
2017-10-05 0:35 ` Kees Cook
2017-10-06 8:33 ` Djalal Harouni
2017-10-05 2:19 ` Tobin C. Harding
2017-10-05 3:10 ` Linus Torvalds
2017-10-05 3:15 ` Kees Cook
2017-10-05 15:12 ` Roberts, William C
2017-10-05 16:19 ` Linus Torvalds
2017-10-05 17:10 ` Dave Weinstein
2017-10-07 23:44 ` Theodore Ts'o
2017-10-08 0:08 ` Linus Torvalds
2017-10-13 16:32 ` Roberts, William C
2017-10-13 18:11 ` Linus Torvalds
2017-10-13 19:34 ` Kees Cook
2017-10-13 20:22 ` Linus Torvalds
2017-10-13 20:47 ` Kees Cook
2017-10-13 21:45 ` Linus Torvalds
2017-10-13 22:48 ` Theodore Ts'o
2017-10-13 16:14 ` Roberts, William C
2017-10-04 16:32 ` Ian Campbell
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