Merge branch 'for-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/jlawall/linux
Pull coccinelle updates from Julia Lawall:
"New semantic patches and semantic patch improvements from Denis
Efremov"
* 'for-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/jlawall/linux:
coccinelle: api: filter out memdup_user definitions
coccinelle: api: extend memdup_user rule with vmemdup_user()
coccinelle: api: extend memdup_user transformation with GFP_USER
coccinelle: api: add kzfree script
coccinelle: misc: add array_size_dup script to detect missed overflow checks
coccinelle: api/kstrdup: fix coccinelle position
coccinelle: api: add device_attr_show script
diff --git a/scripts/coccinelle/api/device_attr_show.cocci b/scripts/coccinelle/api/device_attr_show.cocci
new file mode 100644
index 0000000..d8ec4bb
--- /dev/null
+++ b/scripts/coccinelle/api/device_attr_show.cocci
@@ -0,0 +1,55 @@
+// SPDX-License-Identifier: GPL-2.0-only
+///
+/// From Documentation/filesystems/sysfs.txt:
+/// show() must not use snprintf() when formatting the value to be
+/// returned to user space. If you can guarantee that an overflow
+/// will never happen you can use sprintf() otherwise you must use
+/// scnprintf().
+///
+// Confidence: High
+// Copyright: (C) 2020 Denis Efremov ISPRAS
+// Options: --no-includes --include-headers
+//
+
+virtual report
+virtual org
+virtual context
+virtual patch
+
+@r depends on !patch@
+identifier show, dev, attr, buf;
+position p;
+@@
+
+ssize_t show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ <...
+* return snprintf@p(...);
+ ...>
+}
+
+@rp depends on patch@
+identifier show, dev, attr, buf;
+@@
+
+ssize_t show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ <...
+ return
+- snprintf
++ scnprintf
+ (...);
+ ...>
+}
+
+@script: python depends on report@
+p << r.p;
+@@
+
+coccilib.report.print_report(p[0], "WARNING: use scnprintf or sprintf")
+
+@script: python depends on org@
+p << r.p;
+@@
+
+coccilib.org.print_todo(p[0], "WARNING: use scnprintf or sprintf")
diff --git a/scripts/coccinelle/api/kstrdup.cocci b/scripts/coccinelle/api/kstrdup.cocci
index 19f2645..3c6dc54 100644
--- a/scripts/coccinelle/api/kstrdup.cocci
+++ b/scripts/coccinelle/api/kstrdup.cocci
@@ -66,7 +66,7 @@
* x = strlen(from) + 1;
... when != \( x = E1 \| from = E1 \)
-* to = \(kmalloc@p1\|kzalloc@p2\)(x,flag);
+* to = \(kmalloc@p1\|kzalloc@p1\)(x,flag);
... when != \(x = E2 \| from = E2 \| to = E2 \)
if (to==NULL || ...) S
... when != \(x = E3 \| from = E3 \| to = E3 \)
diff --git a/scripts/coccinelle/api/kzfree.cocci b/scripts/coccinelle/api/kzfree.cocci
new file mode 100644
index 0000000..33625bd
--- /dev/null
+++ b/scripts/coccinelle/api/kzfree.cocci
@@ -0,0 +1,101 @@
+// SPDX-License-Identifier: GPL-2.0-only
+///
+/// Use kzfree, kvfree_sensitive rather than memset or
+/// memzero_explicit followed by kfree
+///
+// Confidence: High
+// Copyright: (C) 2020 Denis Efremov ISPRAS
+// Options: --no-includes --include-headers
+//
+// Keywords: kzfree, kvfree_sensitive
+//
+
+virtual context
+virtual patch
+virtual org
+virtual report
+
+@initialize:python@
+@@
+# kmalloc_oob_in_memset uses memset to explicitly trigger out-of-bounds access
+filter = frozenset(['kmalloc_oob_in_memset', 'kzfree', 'kvfree_sensitive'])
+
+def relevant(p):
+ return not (filter & {el.current_element for el in p})
+
+@cond@
+position ok;
+@@
+
+if (...)
+ \(memset@ok\|memzero_explicit@ok\)(...);
+
+@r depends on !patch forall@
+expression E;
+position p : script:python() { relevant(p) };
+position m != cond.ok;
+type T;
+@@
+
+(
+* memset@m((T)E, 0, ...);
+|
+* memzero_explicit@m((T)E, ...);
+)
+ ... when != E
+ when strict
+* \(kfree\|vfree\|kvfree\)(E)@p;
+
+@rp_memzero depends on patch@
+expression E, size;
+position p : script:python() { relevant(p) };
+position m != cond.ok;
+type T;
+@@
+
+- memzero_explicit@m((T)E, size);
+ ... when != E
+ when strict
+// TODO: uncomment when kfree_sensitive will be merged.
+// Only this case is commented out because developers
+// may not like patches like this since kzfree uses memset
+// internally (not memzero_explicit).
+//(
+//- kfree(E)@p;
+//+ kfree_sensitive(E);
+//|
+- \(vfree\|kvfree\)(E)@p;
++ kvfree_sensitive(E, size);
+//)
+
+@rp_memset depends on patch@
+expression E, size;
+position p : script:python() { relevant(p) };
+position m != cond.ok;
+type T;
+@@
+
+- memset@m((T)E, 0, size);
+ ... when != E
+ when strict
+(
+- kfree(E)@p;
++ kzfree(E);
+|
+- \(vfree\|kvfree\)(E)@p;
++ kvfree_sensitive(E, size);
+)
+
+@script:python depends on report@
+p << r.p;
+@@
+
+coccilib.report.print_report(p[0],
+ "WARNING: opportunity for kzfree/kvfree_sensitive")
+
+@script:python depends on org@
+p << r.p;
+@@
+
+coccilib.org.print_todo(p[0],
+ "WARNING: opportunity for kzfree/kvfree_sensitive")
diff --git a/scripts/coccinelle/api/memdup_user.cocci b/scripts/coccinelle/api/memdup_user.cocci
index c809ab1..e01e951 100644
--- a/scripts/coccinelle/api/memdup_user.cocci
+++ b/scripts/coccinelle/api/memdup_user.cocci
@@ -15,12 +15,22 @@
virtual org
virtual report
+@initialize:python@
+@@
+filter = frozenset(['memdup_user', 'vmemdup_user'])
+
+def relevant(p):
+ return not (filter & {el.current_element for el in p})
+
@depends on patch@
expression from,to,size;
identifier l1,l2;
+position p : script:python() { relevant(p) };
@@
-- to = \(kmalloc\|kzalloc\)(size,GFP_KERNEL);
+- to = \(kmalloc@p\|kzalloc@p\)
+- (size,\(GFP_KERNEL\|GFP_USER\|
+- \(GFP_KERNEL\|GFP_USER\)|__GFP_NOWARN\));
+ to = memdup_user(from,size);
if (
- to==NULL
@@ -37,13 +47,49 @@
- ...+>
- }
+@depends on patch@
+expression from,to,size;
+identifier l1,l2;
+position p : script:python() { relevant(p) };
+@@
+
+- to = \(kvmalloc@p\|kvzalloc@p\)(size,\(GFP_KERNEL\|GFP_USER\));
++ to = vmemdup_user(from,size);
+ if (
+- to==NULL
++ IS_ERR(to)
+ || ...) {
+ <+... when != goto l1;
+- -ENOMEM
++ PTR_ERR(to)
+ ...+>
+ }
+- if (copy_from_user(to, from, size) != 0) {
+- <+... when != goto l2;
+- -EFAULT
+- ...+>
+- }
+
@r depends on !patch@
expression from,to,size;
-position p;
+position p : script:python() { relevant(p) };
statement S1,S2;
@@
-* to = \(kmalloc@p\|kzalloc@p\)(size,GFP_KERNEL);
+* to = \(kmalloc@p\|kzalloc@p\)
+ (size,\(GFP_KERNEL\|GFP_USER\|
+ \(GFP_KERNEL\|GFP_USER\)|__GFP_NOWARN\));
+ if (to==NULL || ...) S1
+ if (copy_from_user(to, from, size) != 0)
+ S2
+
+@rv depends on !patch@
+expression from,to,size;
+position p : script:python() { relevant(p) };
+statement S1,S2;
+@@
+
+* to = \(kvmalloc@p\|kvzalloc@p\)(size,\(GFP_KERNEL\|GFP_USER\));
if (to==NULL || ...) S1
if (copy_from_user(to, from, size) != 0)
S2
@@ -59,3 +105,15 @@
@@
coccilib.report.print_report(p[0], "WARNING opportunity for memdup_user")
+
+@script:python depends on org@
+p << rv.p;
+@@
+
+coccilib.org.print_todo(p[0], "WARNING opportunity for vmemdup_user")
+
+@script:python depends on report@
+p << rv.p;
+@@
+
+coccilib.report.print_report(p[0], "WARNING opportunity for vmemdup_user")
diff --git a/scripts/coccinelle/misc/array_size_dup.cocci b/scripts/coccinelle/misc/array_size_dup.cocci
new file mode 100644
index 0000000..fbc2ba1
--- /dev/null
+++ b/scripts/coccinelle/misc/array_size_dup.cocci
@@ -0,0 +1,209 @@
+// SPDX-License-Identifier: GPL-2.0-only
+///
+/// Check for array_size(), array3_size(), struct_size() duplicates.
+/// These patterns are detected:
+/// 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
+/// 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 subE2 <= as.E2;
+expression as.E1, as.E2, E3;
+assignment operator aop;
+position p1, p2;
+@@
+
+* E1 * E2@p1
+ ... when != \(subE1\|subE2\) aop E3
+ when != &\(subE1\|subE2\)
+* array_size(E1, E2)@p2
+
+@script:python depends on report@
+p1 << as_next.p1;
+p2 << as_next.p2;
+@@
+
+msg = "WARNING: array_size is used later (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 later (line %s) to compute the same size" % (p2[0].line)
+coccilib.org.print_todo(p1[0], msg)
+
+@as_prev@
+expression subE1 <= as.E1;
+expression subE2 <= as.E2;
+expression as.E1, as.E2, E3;
+assignment operator aop;
+position p1, p2;
+@@
+
+* array_size(E1, E2)@p1
+ ... when != \(subE1\|subE2\) aop E3
+ when != &\(subE1\|subE2\)
+* E1 * E2@p2
+
+@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)
+
+@as3@
+expression E1, E2, E3;
+@@
+
+array3_size(E1, E2, E3)
+
+@as3_next@
+expression subE1 <= as3.E1;
+expression subE2 <= as3.E2;
+expression subE3 <= as3.E3;
+expression as3.E1, as3.E2, as3.E3, E4;
+assignment operator aop;
+position p1, p2;
+@@
+
+* E1 * E2 * E3@p1
+ ... when != \(subE1\|subE2\|subE3\) aop E4
+ when != &\(subE1\|subE2\|subE3\)
+* array3_size(E1, E2, E3)@p2
+
+@script:python depends on report@
+p1 << as3_next.p1;
+p2 << as3_next.p2;
+@@
+
+msg = "WARNING: array3_size is used later (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 later (line %s) to compute the same size" % (p2[0].line)
+coccilib.org.print_todo(p1[0], msg)
+
+@as3_prev@
+expression subE1 <= as3.E1;
+expression subE2 <= as3.E2;
+expression subE3 <= as3.E3;
+expression as3.E1, as3.E2, as3.E3, E4;
+assignment operator aop;
+position p1, p2;
+@@
+
+* array3_size(E1, E2, E3)@p1
+ ... when != \(subE1\|subE2\|subE3\) aop E4
+ when != &\(subE1\|subE2\|subE3\)
+* E1 * E2 * E3@p2
+
+@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)
+
+@ss@
+expression E1, E2, E3;
+@@
+
+struct_size(E1, E2, E3)
+
+@ss_next@
+expression subE3 <= ss.E3;
+expression ss.E1, ss.E2, ss.E3, E4;
+assignment operator aop;
+position p1, p2;
+@@
+
+* E1 * E2 + E3@p1
+ ... when != subE3 aop E4
+ when != &subE3
+* struct_size(E1, E2, E3)@p2
+
+@script:python depends on report@
+p1 << ss_next.p1;
+p2 << ss_next.p2;
+@@
+
+msg = "WARNING: struct_size is used later (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 later (line %s) to compute the same size" % (p2[0].line)
+coccilib.org.print_todo(p1[0], msg)
+
+@ss_prev@
+expression subE3 <= ss.E3;
+expression ss.E1, ss.E2, ss.E3, E4;
+assignment operator aop;
+position p1, p2;
+@@
+
+* struct_size(E1, E2, E3)@p1
+ ... when != subE3 aop E4
+ when != &subE3
+* E1 * E2 + E3@p2
+
+@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)
