All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH] coccinelle: misc: add array_size_dup script to detect missed overlow checks
@ 2020-06-15 10:20 ` Denis Efremov
  0 siblings, 0 replies; 56+ messages in thread
From: Denis Efremov @ 2020-06-15 10:20 UTC (permalink / raw)
  To: Julia Lawall; +Cc: Denis Efremov, cocci, linux-kernel, Kees Cook

Detect an opencoded expression that is used before or after
array_size()/array3_size()/struct_size() to compute the same size.

Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Denis Efremov <efremov@linux.com>
---
 scripts/coccinelle/misc/array_size_dup.cocci | 347 +++++++++++++++++++
 1 file changed, 347 insertions(+)
 create mode 100644 scripts/coccinelle/misc/array_size_dup.cocci

diff --git a/scripts/coccinelle/misc/array_size_dup.cocci b/scripts/coccinelle/misc/array_size_dup.cocci
new file mode 100644
index 000000000000..08919a938754
--- /dev/null
+++ b/scripts/coccinelle/misc/array_size_dup.cocci
@@ -0,0 +1,347 @@
+// SPDX-License-Identifier: GPL-2.0-only
+///
+/// Check for array_size(), array3_size(), struct_size() duplicates.
+/// Three types of patterns for these functions:
+///  1. An opencoded expression is used before array_size() to compute the same size
+///  2. An opencoded expression is used after array_size() to compute the same size
+///  3. Consecutive calls of array_size() with the same values
+/// From security point of view only first case is relevant. These functions
+/// perform arithmetic overflow check. Thus, if we use an opencoded expression
+/// before a call to the *_size() function we can miss an overflow.
+///
+// Confidence: High
+// Copyright: (C) 2020 Denis Efremov ISPRAS
+// Options: --no-includes --include-headers --no-loops
+
+virtual context
+virtual report
+virtual org
+
+@as@
+expression E1, E2;
+@@
+
+array_size(E1, E2)
+
+@as_next@
+expression subE1 <= as.E1;
+expression as.E1;
+expression subE2 <= as.E2;
+expression as.E2;
+expression E3;
+position p1, p2;
+@@
+
+* E1 * E2@p1
+  ... when != \(E1\|E2\|subE1\|subE2\)=E3
+      when != \(E1\|E2\|subE1\|subE2\)+=E3
+      when != \(E1\|E2\|subE1\|subE2\)-=E3
+      when != \(E1\|E2\|subE1\|subE2\)*=E3
+      when != \(&E1\|&E2\|&subE1\|&subE2\)
+* array_size(E1, E2)@p2
+
+@as_prev@
+expression subE1 <= as.E1;
+expression as.E1;
+expression subE2 <= as.E2;
+expression as.E2;
+expression E3;
+position p1, p2;
+@@
+
+* array_size(E1, E2)@p1
+  ... when != \(E1\|E2\|subE1\|subE2\)=E3
+      when != \(E1\|E2\|subE1\|subE2\)+=E3
+      when != \(E1\|E2\|subE1\|subE2\)-=E3
+      when != \(E1\|E2\|subE1\|subE2\)*=E3
+      when != \(&E1\|&E2\|&subE1\|&subE2\)
+* E1 * E2@p2
+
+@as_dup@
+expression subE1 <= as.E1;
+expression as.E1;
+expression subE2 <= as.E2;
+expression as.E2;
+expression E3;
+position p1, p2;
+@@
+
+* array_size(E1, E2)@p1
+  ... when != \(E1\|E2\|subE1\|subE2\)=E3
+      when != \(E1\|E2\|subE1\|subE2\)+=E3
+      when != \(E1\|E2\|subE1\|subE2\)-=E3
+      when != \(E1\|E2\|subE1\|subE2\)*=E3
+      when != \(&E1\|&E2\|&subE1\|&subE2\)
+* array_size(E1, E2)@p2
+
+@as3@
+expression E1, E2, E3;
+@@
+
+array3_size(E1, E2, E3)
+
+@as3_next@
+expression subE1 <= as3.E1;
+expression as3.E1;
+expression subE2 <= as3.E2;
+expression as3.E2;
+expression subE3 <= as3.E3;
+expression as3.E3;
+expression E4;
+position p1, p2;
+@@
+
+* E1 * E2 * E3@p1
+  ... when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)=E4
+      when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)+=E4
+      when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)-=E4
+      when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)*=E4
+      when != \(&E1\|&E2\|&E3\|&subE1\|&subE2\|&subE3\)
+* array3_size(E1, E2, E3)@p2
+
+@as3_prev@
+expression subE1 <= as3.E1;
+expression as3.E1;
+expression subE2 <= as3.E2;
+expression as3.E2;
+expression subE3 <= as3.E3;
+expression as3.E3;
+expression E4;
+position p1, p2;
+@@
+
+* array3_size(E1, E2, E3)@p1
+  ... when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)=E4
+      when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)+=E4
+      when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)-=E4
+      when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)*=E4
+      when != \(&E1\|&E2\|&E3\|&subE1\|&subE2\|&subE3\)
+* E1 * E2 * E3@p2
+
+@as3_dup@
+expression subE1 <= as3.E1;
+expression as3.E1;
+expression subE2 <= as3.E2;
+expression as3.E2;
+expression subE3 <= as3.E3;
+expression as3.E3;
+expression E4;
+position p1, p2;
+@@
+
+* array3_size(E1, E2, E3)@p1
+  ... when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)=E4
+      when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)+=E4
+      when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)-=E4
+      when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)*=E4
+      when != \(&E1\|&E2\|&E3\|&subE1\|&subE2\|&subE3\)
+* array3_size(E1, E2, E3)@p2
+
+@ss@
+expression E1, E2, E3;
+@@
+
+struct_size(E1, E2, E3)
+
+@ss_next@
+expression subE1 <= ss.E1;
+expression ss.E1;
+expression subE2 <= ss.E2;
+expression ss.E2;
+expression subE3 <= ss.E3;
+expression ss.E3;
+expression E4;
+position p1, p2;
+@@
+
+* E1 * E2 + E3@p1
+  ... when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)=E4
+      when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)+=E4
+      when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)-=E4
+      when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)*=E4
+      when != \(&E1\|&E2\|&E3\|&subE1\|&subE2\|&subE3\)
+* struct_size(E1, E2, E3)@p2
+
+@ss_prev@
+expression subE1 <= ss.E1;
+expression ss.E1;
+expression subE2 <= ss.E2;
+expression ss.E2;
+expression subE3 <= ss.E3;
+expression ss.E3;
+expression E4;
+position p1, p2;
+@@
+
+* struct_size(E1, E2, E3)@p1
+  ... when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)=E4
+      when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)+=E4
+      when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)-=E4
+      when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)*=E4
+      when != \(&E1\|&E2\|&E3\|&subE1\|&subE2\|&subE3\)
+* E1 * E2 + E3@p2
+
+@ss_dup@
+expression subE1 <= ss.E1;
+expression ss.E1;
+expression subE2 <= ss.E2;
+expression ss.E2;
+expression subE3 <= ss.E3;
+expression ss.E3;
+expression E4;
+position p1, p2;
+@@
+
+* struct_size(E1, E2, E3)@p1
+  ... when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)=E4
+      when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)+=E4
+      when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)-=E4
+      when != \(E1\|E2\|E3\|subE1\|subE2\|subE3\)*=E4
+      when != \(&E1\|&E2\|&E3\|&subE1\|&subE2\|&subE3\)
+* struct_size(E1, E2, E3)@p2
+
+@script:python depends on report@
+p1 << as_next.p1;
+p2 << as_next.p2;
+@@
+
+msg = "WARNING: array_size is used down the code (line %s) to compute the same size" % (p2[0].line)
+coccilib.report.print_report(p1[0], msg)
+
+@script:python depends on org@
+p1 << as_next.p1;
+p2 << as_next.p2;
+@@
+
+msg = "WARNING: array_size is used down the code (line %s) to compute the same size" % (p2[0].line)
+coccilib.org.print_todo(p1[0], msg)
+
+@script:python depends on report@
+p1 << as_prev.p1;
+p2 << as_prev.p2;
+@@
+
+msg = "WARNING: array_size is already used (line %s) to compute the same size" % (p1[0].line)
+coccilib.report.print_report(p2[0], msg)
+
+@script:python depends on org@
+p1 << as_prev.p1;
+p2 << as_prev.p2;
+@@
+
+msg = "WARNING: array_size is already used (line %s) to compute the same size" % (p1[0].line)
+coccilib.org.print_todo(p2[0], msg)
+
+@script:python depends on report@
+p1 << as_dup.p1;
+p2 << as_dup.p2;
+@@
+
+msg = "WARNING: same array_size (line %s)" % (p1[0].line)
+coccilib.report.print_report(p2[0], msg)
+
+@script:python depends on org@
+p1 << as_dup.p1;
+p2 << as_dup.p2;
+@@
+
+msg = "WARNING: same array_size (line %s)" % (p1[0].line)
+coccilib.org.print_todo(p2[0], msg)
+
+
+@script:python depends on report@
+p1 << as3_next.p1;
+p2 << as3_next.p2;
+@@
+
+msg = "WARNING: array3_size is used down the code (line %s) to compute the same size" % (p2[0].line)
+coccilib.report.print_report(p1[0], msg)
+
+@script:python depends on org@
+p1 << as3_next.p1;
+p2 << as3_next.p2;
+@@
+
+msg = "WARNING: array3_size is used down the code (line %s) to compute the same size" % (p2[0].line)
+coccilib.org.print_todo(p1[0], msg)
+
+@script:python depends on report@
+p1 << as3_prev.p1;
+p2 << as3_prev.p2;
+@@
+
+msg = "WARNING: array3_size is already used (line %s) to compute the same size" % (p1[0].line)
+coccilib.report.print_report(p2[0], msg)
+
+@script:python depends on org@
+p1 << as3_prev.p1;
+p2 << as3_prev.p2;
+@@
+
+msg = "WARNING: array3_size is already used (line %s) to compute the same size" % (p1[0].line)
+coccilib.org.print_todo(p2[0], msg)
+
+@script:python depends on report@
+p1 << as3_dup.p1;
+p2 << as3_dup.p2;
+@@
+
+msg = "WARNING: same array3_size (line %s)" % (p1[0].line)
+coccilib.report.print_report(p2[0], msg)
+
+@script:python depends on org@
+p1 << as3_dup.p1;
+p2 << as3_dup.p2;
+@@
+
+msg = "WARNING: same array3_size (line %s)" % (p1[0].line)
+coccilib.org.print_todo(p2[0], msg)
+
+
+@script:python depends on report@
+p1 << ss_next.p1;
+p2 << ss_next.p2;
+@@
+
+msg = "WARNING: struct_size is used down the code (line %s) to compute the same size" % (p2[0].line)
+coccilib.report.print_report(p1[0], msg)
+
+@script:python depends on org@
+p1 << ss_next.p1;
+p2 << ss_next.p2;
+@@
+
+msg = "WARNING: struct_size is used down the code (line %s) to compute the same size" % (p2[0].line)
+coccilib.org.print_todo(p1[0], msg)
+
+@script:python depends on report@
+p1 << ss_prev.p1;
+p2 << ss_prev.p2;
+@@
+
+msg = "WARNING: struct_size is already used (line %s) to compute the same size" % (p1[0].line)
+coccilib.report.print_report(p2[0], msg)
+
+@script:python depends on org@
+p1 << ss_prev.p1;
+p2 << ss_prev.p2;
+@@
+
+msg = "WARNING: struct_size is already used (line %s) to compute the same size" % (p1[0].line)
+coccilib.org.print_todo(p2[0], msg)
+
+@script:python depends on report@
+p1 << ss_dup.p1;
+p2 << ss_dup.p2;
+@@
+
+msg = "WARNING: same struct_size (line %s)" % (p1[0].line)
+coccilib.report.print_report(p2[0], msg)
+
+@script:python depends on org@
+p1 << ss_dup.p1;
+p2 << ss_dup.p2;
+@@
+
+msg = "WARNING: same struct_size (line %s)" % (p1[0].line)
+coccilib.org.print_todo(p2[0], msg)
-- 
2.26.2


^ permalink raw reply related	[flat|nested] 56+ messages in thread
* Re: [PATCH v4] coccinelle: misc: add array_size_dup script to detect missed overflow checks
@ 2020-06-23  6:12 ` Markus Elfring
  0 siblings, 0 replies; 56+ messages in thread
From: Markus Elfring @ 2020-06-23  6:12 UTC (permalink / raw)
  To: Denis Efremov, Coccinelle, Gilles Muller, Julia Lawall,
	Masahiro Yamada, Michal Marek, Nicolas Palix
  Cc: linux-kernel, kernel-janitors, Gustavo A. R. Silva, Kees Cook

> Changes in v2:
> - assignment operator used

I prefer the distinction for the application of corresponding metavariables.


> Changes in v3:
>  - \(&E1\|&E2\) changed to &\(E1\|E2\)

Would it be more helpful to mention the movement of the ampersand
before SmPL disjunctions?


…
>+/// Three types of patterns for these functions:

Will another adjustment be needed according to your information “duplicates warning removed”?


…
> +virtual context
> +virtual report
> +virtual org

Can the following SmPL code variant ever become more attractive?

+virtual context, report, org


…
> +expression subE1 <= as.E1;
> +expression subE2 <= as.E2;
> +expression as.E1, as.E2, E3;

How do you think about the following SmPL code variant?

+expression subE1 <= as.E1,
+           subE2 <= as.E2,
+           as.E1, as.E2, E3;


…
> +msg = "WARNING: array_size is used later (line %s) to compute the same size" % (p2[0].line)
> +coccilib.report.print_report(p1[0], msg)

Please omit the extra Python variable “msg” for the passing of such simple message objects.

What does hinder you to take the proposed script variants better into account?

Regards,
Markus

^ permalink raw reply	[flat|nested] 56+ messages in thread

end of thread, other threads:[~2020-06-24 19:43 UTC | newest]

Thread overview: 56+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-06-15 10:20 [PATCH] coccinelle: misc: add array_size_dup script to detect missed overlow checks Denis Efremov
2020-06-15 10:20 ` [Cocci] " Denis Efremov
2020-06-15 18:23 ` Kees Cook
2020-06-15 18:23   ` [Cocci] " Kees Cook
2020-06-15 18:35   ` Denis Efremov
2020-06-15 18:35     ` [Cocci] " Denis Efremov
2020-06-15 18:46     ` Gustavo A. R. Silva
2020-06-15 18:46       ` Gustavo A. R. Silva
2020-06-17  9:32       ` Denis Efremov
2020-06-17  9:32         ` Denis Efremov
2020-06-17 10:55       ` Denis Efremov
2020-06-17 10:55         ` Denis Efremov
2020-06-17 20:08         ` Julia Lawall
2020-06-17 20:08           ` Julia Lawall
2020-06-17 20:15           ` Julia Lawall
2020-06-17 20:15             ` Julia Lawall
2020-06-17 18:15 ` Kees Cook
2020-06-17 18:15   ` [Cocci] " Kees Cook
2020-06-17 18:54   ` Julia Lawall
2020-06-17 18:54     ` Julia Lawall
2020-06-18 19:52     ` Kees Cook
2020-06-18 19:52       ` Kees Cook
2020-06-18 19:56       ` Julia Lawall
2020-06-18 19:56         ` Julia Lawall
2020-06-18 20:48         ` Kees Cook
2020-06-18 20:48           ` Kees Cook
2020-06-18 21:08           ` Julia Lawall
2020-06-18 21:08             ` Julia Lawall
2020-06-17 20:30 ` Julia Lawall
2020-06-17 20:30   ` Julia Lawall
2020-06-17 20:50   ` Denis Efremov
2020-06-17 20:50     ` Denis Efremov
2020-06-17 20:52     ` Julia Lawall
2020-06-17 20:52       ` Julia Lawall
2020-06-18 10:23 ` [PATCH v2] " Denis Efremov
2020-06-18 10:23   ` [Cocci] " Denis Efremov
2020-06-19 13:13 ` [PATCH v3] coccinelle: misc: add array_size_dup script to detect missed overflow checks Denis Efremov
2020-06-19 13:13   ` [Cocci] " Denis Efremov
2020-06-21 20:53   ` Julia Lawall
2020-06-21 20:53     ` Julia Lawall
2020-06-21 20:56   ` Julia Lawall
2020-06-21 20:56     ` Julia Lawall
2020-06-22 12:12     ` Denis Efremov
2020-06-22 12:12       ` Denis Efremov
2020-06-22 12:16     ` Denis Efremov
2020-06-22 12:16       ` Denis Efremov
2020-06-22 12:19       ` Julia Lawall
2020-06-22 12:19         ` Julia Lawall
2020-06-22 22:10 ` [PATCH v4] " Denis Efremov
2020-06-22 22:10   ` [Cocci] " Denis Efremov
2020-06-24 19:42   ` Julia Lawall
2020-06-24 19:42     ` [Cocci] " Julia Lawall
2020-06-23  6:12 Markus Elfring
2020-06-23  6:12 ` Markus Elfring
2020-06-23  7:02 ` Julia Lawall
2020-06-23  7:02   ` Julia Lawall

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.