diff mbox series

[v2,16/17] kernel/sysctl-test: Add null pointer test for sysctl.c:proc_dointvec()

Message ID 20190501230126.229218-17-brendanhiggins@google.com (mailing list archive)
State Superseded
Headers show
Series kunit: introduce KUnit, the Linux kernel unit testing framework | expand

Commit Message

Brendan Higgins May 1, 2019, 11:01 p.m. UTC
From: Iurii Zaikin <yzaikin@google.com>

KUnit tests for initialized data behavior of proc_dointvec that is
explicitly checked in the code. Includes basic parsing tests including
int min/max overflow.

Signed-off-by: Iurii Zaikin <yzaikin@google.com>
Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
---
 kernel/Makefile      |   2 +
 kernel/sysctl-test.c | 292 +++++++++++++++++++++++++++++++++++++++++++
 lib/Kconfig.debug    |   6 +
 3 files changed, 300 insertions(+)
 create mode 100644 kernel/sysctl-test.c

Comments

Greg Kroah-Hartman May 2, 2019, 11:03 a.m. UTC | #1
On Wed, May 01, 2019 at 04:01:25PM -0700, Brendan Higgins wrote:
> From: Iurii Zaikin <yzaikin@google.com>
> 
> KUnit tests for initialized data behavior of proc_dointvec that is
> explicitly checked in the code. Includes basic parsing tests including
> int min/max overflow.
> 
> Signed-off-by: Iurii Zaikin <yzaikin@google.com>
> Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
> ---
>  kernel/Makefile      |   2 +
>  kernel/sysctl-test.c | 292 +++++++++++++++++++++++++++++++++++++++++++
>  lib/Kconfig.debug    |   6 +
>  3 files changed, 300 insertions(+)
>  create mode 100644 kernel/sysctl-test.c
> 
> diff --git a/kernel/Makefile b/kernel/Makefile
> index 6c57e78817dad..c81a8976b6a4b 100644
> --- a/kernel/Makefile
> +++ b/kernel/Makefile
> @@ -112,6 +112,8 @@ obj-$(CONFIG_HAS_IOMEM) += iomem.o
>  obj-$(CONFIG_ZONE_DEVICE) += memremap.o
>  obj-$(CONFIG_RSEQ) += rseq.o
>  
> +obj-$(CONFIG_SYSCTL_KUNIT_TEST) += sysctl-test.o

You are going to have to have a "standard" naming scheme for test
modules, are you going to recommend "foo-test" over "test-foo"?  If so,
that's fine, we should just be consistant and document it somewhere.

Personally, I'd prefer "test-foo", but that's just me, naming is hard...

thanks,

greg k-h
Bird, Tim May 2, 2019, 6:14 p.m. UTC | #2
> -----Original Message-----
> From: Greg KH 
> 
> On Wed, May 01, 2019 at 04:01:25PM -0700, Brendan Higgins wrote:
> > From: Iurii Zaikin <yzaikin@google.com>
> >
> > KUnit tests for initialized data behavior of proc_dointvec that is
> > explicitly checked in the code. Includes basic parsing tests including
> > int min/max overflow.
> >
> > Signed-off-by: Iurii Zaikin <yzaikin@google.com>
> > Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
> > ---
> >  kernel/Makefile      |   2 +
> >  kernel/sysctl-test.c | 292
> +++++++++++++++++++++++++++++++++++++++++++
> >  lib/Kconfig.debug    |   6 +
> >  3 files changed, 300 insertions(+)
> >  create mode 100644 kernel/sysctl-test.c
> >
> > diff --git a/kernel/Makefile b/kernel/Makefile
> > index 6c57e78817dad..c81a8976b6a4b 100644
> > --- a/kernel/Makefile
> > +++ b/kernel/Makefile
> > @@ -112,6 +112,8 @@ obj-$(CONFIG_HAS_IOMEM) += iomem.o
> >  obj-$(CONFIG_ZONE_DEVICE) += memremap.o
> >  obj-$(CONFIG_RSEQ) += rseq.o
> >
> > +obj-$(CONFIG_SYSCTL_KUNIT_TEST) += sysctl-test.o
> 
> You are going to have to have a "standard" naming scheme for test
> modules, are you going to recommend "foo-test" over "test-foo"?  If so,
> that's fine, we should just be consistant and document it somewhere.
> 
> Personally, I'd prefer "test-foo", but that's just me, naming is hard...

My preference would be "test-foo" as well.  Just my 2 cents.
 -- Tim
Brendan Higgins May 2, 2019, 6:45 p.m. UTC | #3
On Thu, May 2, 2019 at 11:15 AM <Tim.Bird@sony.com> wrote:
>
>
>
> > -----Original Message-----
> > From: Greg KH
> >
> > On Wed, May 01, 2019 at 04:01:25PM -0700, Brendan Higgins wrote:
> > > From: Iurii Zaikin <yzaikin@google.com>
> > >
> > > KUnit tests for initialized data behavior of proc_dointvec that is
> > > explicitly checked in the code. Includes basic parsing tests including
> > > int min/max overflow.
> > >
> > > Signed-off-by: Iurii Zaikin <yzaikin@google.com>
> > > Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
> > > ---
> > >  kernel/Makefile      |   2 +
> > >  kernel/sysctl-test.c | 292
> > +++++++++++++++++++++++++++++++++++++++++++
> > >  lib/Kconfig.debug    |   6 +
> > >  3 files changed, 300 insertions(+)
> > >  create mode 100644 kernel/sysctl-test.c
> > >
> > > diff --git a/kernel/Makefile b/kernel/Makefile
> > > index 6c57e78817dad..c81a8976b6a4b 100644
> > > --- a/kernel/Makefile
> > > +++ b/kernel/Makefile
> > > @@ -112,6 +112,8 @@ obj-$(CONFIG_HAS_IOMEM) += iomem.o
> > >  obj-$(CONFIG_ZONE_DEVICE) += memremap.o
> > >  obj-$(CONFIG_RSEQ) += rseq.o
> > >
> > > +obj-$(CONFIG_SYSCTL_KUNIT_TEST) += sysctl-test.o
> >
> > You are going to have to have a "standard" naming scheme for test
> > modules, are you going to recommend "foo-test" over "test-foo"?  If so,
> > that's fine, we should just be consistant and document it somewhere.
> >
> > Personally, I'd prefer "test-foo", but that's just me, naming is hard...
>
> My preference would be "test-foo" as well.  Just my 2 cents.

I definitely agree we should be consistent. My personal bias
(unsurprisingly) is "foo-test," but this is just because that is the
convention I am used to in other projects I have worked on.

On an unbiased note, we are currently almost evenly split between the
two conventions with *slight* preference for "foo-test": I ran the two
following grep commands on v5.1-rc7:

grep -Hrn --exclude-dir="build" -e "config [a-zA-Z_0-9]\+_TEST$" | wc -l
grep -Hrn --exclude-dir="build" -e "config TEST_[a-zA-Z_0-9]\+" | wc -l

"foo-test" has 36 occurrences.
"test-foo" has 33 occurrences.

The things I am more concerned about is how this would affect file
naming. If we have a unit test for foo.c, I think foo_test.c is more
consistent with our namespacing conventions. The other thing, is if we
already have a Kconfig symbol called FOO_TEST (or TEST_FOO) what
should we name the KUnit test in this case? FOO_UNIT_TEST?
FOO_KUNIT_TEST, like I did above?

Cheers
Greg Kroah-Hartman May 3, 2019, 6:42 a.m. UTC | #4
On Thu, May 02, 2019 at 11:45:43AM -0700, Brendan Higgins wrote:
> On Thu, May 2, 2019 at 11:15 AM <Tim.Bird@sony.com> wrote:
> >
> >
> >
> > > -----Original Message-----
> > > From: Greg KH
> > >
> > > On Wed, May 01, 2019 at 04:01:25PM -0700, Brendan Higgins wrote:
> > > > From: Iurii Zaikin <yzaikin@google.com>
> > > >
> > > > KUnit tests for initialized data behavior of proc_dointvec that is
> > > > explicitly checked in the code. Includes basic parsing tests including
> > > > int min/max overflow.
> > > >
> > > > Signed-off-by: Iurii Zaikin <yzaikin@google.com>
> > > > Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
> > > > ---
> > > >  kernel/Makefile      |   2 +
> > > >  kernel/sysctl-test.c | 292
> > > +++++++++++++++++++++++++++++++++++++++++++
> > > >  lib/Kconfig.debug    |   6 +
> > > >  3 files changed, 300 insertions(+)
> > > >  create mode 100644 kernel/sysctl-test.c
> > > >
> > > > diff --git a/kernel/Makefile b/kernel/Makefile
> > > > index 6c57e78817dad..c81a8976b6a4b 100644
> > > > --- a/kernel/Makefile
> > > > +++ b/kernel/Makefile
> > > > @@ -112,6 +112,8 @@ obj-$(CONFIG_HAS_IOMEM) += iomem.o
> > > >  obj-$(CONFIG_ZONE_DEVICE) += memremap.o
> > > >  obj-$(CONFIG_RSEQ) += rseq.o
> > > >
> > > > +obj-$(CONFIG_SYSCTL_KUNIT_TEST) += sysctl-test.o
> > >
> > > You are going to have to have a "standard" naming scheme for test
> > > modules, are you going to recommend "foo-test" over "test-foo"?  If so,
> > > that's fine, we should just be consistant and document it somewhere.
> > >
> > > Personally, I'd prefer "test-foo", but that's just me, naming is hard...
> >
> > My preference would be "test-foo" as well.  Just my 2 cents.
> 
> I definitely agree we should be consistent. My personal bias
> (unsurprisingly) is "foo-test," but this is just because that is the
> convention I am used to in other projects I have worked on.
> 
> On an unbiased note, we are currently almost evenly split between the
> two conventions with *slight* preference for "foo-test": I ran the two
> following grep commands on v5.1-rc7:
> 
> grep -Hrn --exclude-dir="build" -e "config [a-zA-Z_0-9]\+_TEST$" | wc -l
> grep -Hrn --exclude-dir="build" -e "config TEST_[a-zA-Z_0-9]\+" | wc -l
> 
> "foo-test" has 36 occurrences.
> "test-foo" has 33 occurrences.
> 
> The things I am more concerned about is how this would affect file
> naming. If we have a unit test for foo.c, I think foo_test.c is more
> consistent with our namespacing conventions. The other thing, is if we
> already have a Kconfig symbol called FOO_TEST (or TEST_FOO) what
> should we name the KUnit test in this case? FOO_UNIT_TEST?
> FOO_KUNIT_TEST, like I did above?

Ok, I can live with "foo-test", as you are right, in a directory listing
and config option, it makes more sense to add it as a suffix.

thanks,

greg k-h
Brendan Higgins May 3, 2019, 11:41 p.m. UTC | #5
> On Thu, May 02, 2019 at 11:45:43AM -0700, Brendan Higgins wrote:
> > On Thu, May 2, 2019 at 11:15 AM <Tim.Bird@sony.com> wrote:
> > >
> > >
> > >
> > > > -----Original Message-----
> > > > From: Greg KH
> > > >
> > > > On Wed, May 01, 2019 at 04:01:25PM -0700, Brendan Higgins wrote:
> > > > > From: Iurii Zaikin <yzaikin@google.com>
> > > > >
> > > > > KUnit tests for initialized data behavior of proc_dointvec that is
> > > > > explicitly checked in the code. Includes basic parsing tests including
> > > > > int min/max overflow.
> > > > >
> > > > > Signed-off-by: Iurii Zaikin <yzaikin@google.com>
> > > > > Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
> > > > > ---
> > > > >  kernel/Makefile      |   2 +
> > > > >  kernel/sysctl-test.c | 292
> > > > +++++++++++++++++++++++++++++++++++++++++++
> > > > >  lib/Kconfig.debug    |   6 +
> > > > >  3 files changed, 300 insertions(+)
> > > > >  create mode 100644 kernel/sysctl-test.c
> > > > >
> > > > > diff --git a/kernel/Makefile b/kernel/Makefile
> > > > > index 6c57e78817dad..c81a8976b6a4b 100644
> > > > > --- a/kernel/Makefile
> > > > > +++ b/kernel/Makefile
> > > > > @@ -112,6 +112,8 @@ obj-$(CONFIG_HAS_IOMEM) += iomem.o
> > > > >  obj-$(CONFIG_ZONE_DEVICE) += memremap.o
> > > > >  obj-$(CONFIG_RSEQ) += rseq.o
> > > > >
> > > > > +obj-$(CONFIG_SYSCTL_KUNIT_TEST) += sysctl-test.o
> > > >
> > > > You are going to have to have a "standard" naming scheme for test
> > > > modules, are you going to recommend "foo-test" over "test-foo"?  If so,
> > > > that's fine, we should just be consistant and document it somewhere.
> > > >
> > > > Personally, I'd prefer "test-foo", but that's just me, naming is hard...
> > >
> > > My preference would be "test-foo" as well.  Just my 2 cents.
> >
> > I definitely agree we should be consistent. My personal bias
> > (unsurprisingly) is "foo-test," but this is just because that is the
> > convention I am used to in other projects I have worked on.
> >
> > On an unbiased note, we are currently almost evenly split between the
> > two conventions with *slight* preference for "foo-test": I ran the two
> > following grep commands on v5.1-rc7:
> >
> > grep -Hrn --exclude-dir="build" -e "config [a-zA-Z_0-9]\+_TEST$" | wc -l
> > grep -Hrn --exclude-dir="build" -e "config TEST_[a-zA-Z_0-9]\+" | wc -l
> >
> > "foo-test" has 36 occurrences.
> > "test-foo" has 33 occurrences.
> >
> > The things I am more concerned about is how this would affect file
> > naming. If we have a unit test for foo.c, I think foo_test.c is more
> > consistent with our namespacing conventions. The other thing, is if we
> > already have a Kconfig symbol called FOO_TEST (or TEST_FOO) what
> > should we name the KUnit test in this case? FOO_UNIT_TEST?
> > FOO_KUNIT_TEST, like I did above?
>
> Ok, I can live with "foo-test", as you are right, in a directory listing
> and config option, it makes more sense to add it as a suffix.

Cool, so just for future reference, if we already have a Kconfig
symbol called FOO_TEST (or TEST_FOO) what should we name the KUnit
test in this case? FOO_UNIT_TEST? FOO_KUNIT_TEST, like I did above?
Greg Kroah-Hartman May 4, 2019, 10:40 a.m. UTC | #6
On Fri, May 03, 2019 at 04:41:10PM -0700, Brendan Higgins wrote:
> > On Thu, May 02, 2019 at 11:45:43AM -0700, Brendan Higgins wrote:
> > > On Thu, May 2, 2019 at 11:15 AM <Tim.Bird@sony.com> wrote:
> > > >
> > > >
> > > >
> > > > > -----Original Message-----
> > > > > From: Greg KH
> > > > >
> > > > > On Wed, May 01, 2019 at 04:01:25PM -0700, Brendan Higgins wrote:
> > > > > > From: Iurii Zaikin <yzaikin@google.com>
> > > > > >
> > > > > > KUnit tests for initialized data behavior of proc_dointvec that is
> > > > > > explicitly checked in the code. Includes basic parsing tests including
> > > > > > int min/max overflow.
> > > > > >
> > > > > > Signed-off-by: Iurii Zaikin <yzaikin@google.com>
> > > > > > Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
> > > > > > ---
> > > > > >  kernel/Makefile      |   2 +
> > > > > >  kernel/sysctl-test.c | 292
> > > > > +++++++++++++++++++++++++++++++++++++++++++
> > > > > >  lib/Kconfig.debug    |   6 +
> > > > > >  3 files changed, 300 insertions(+)
> > > > > >  create mode 100644 kernel/sysctl-test.c
> > > > > >
> > > > > > diff --git a/kernel/Makefile b/kernel/Makefile
> > > > > > index 6c57e78817dad..c81a8976b6a4b 100644
> > > > > > --- a/kernel/Makefile
> > > > > > +++ b/kernel/Makefile
> > > > > > @@ -112,6 +112,8 @@ obj-$(CONFIG_HAS_IOMEM) += iomem.o
> > > > > >  obj-$(CONFIG_ZONE_DEVICE) += memremap.o
> > > > > >  obj-$(CONFIG_RSEQ) += rseq.o
> > > > > >
> > > > > > +obj-$(CONFIG_SYSCTL_KUNIT_TEST) += sysctl-test.o
> > > > >
> > > > > You are going to have to have a "standard" naming scheme for test
> > > > > modules, are you going to recommend "foo-test" over "test-foo"?  If so,
> > > > > that's fine, we should just be consistant and document it somewhere.
> > > > >
> > > > > Personally, I'd prefer "test-foo", but that's just me, naming is hard...
> > > >
> > > > My preference would be "test-foo" as well.  Just my 2 cents.
> > >
> > > I definitely agree we should be consistent. My personal bias
> > > (unsurprisingly) is "foo-test," but this is just because that is the
> > > convention I am used to in other projects I have worked on.
> > >
> > > On an unbiased note, we are currently almost evenly split between the
> > > two conventions with *slight* preference for "foo-test": I ran the two
> > > following grep commands on v5.1-rc7:
> > >
> > > grep -Hrn --exclude-dir="build" -e "config [a-zA-Z_0-9]\+_TEST$" | wc -l
> > > grep -Hrn --exclude-dir="build" -e "config TEST_[a-zA-Z_0-9]\+" | wc -l
> > >
> > > "foo-test" has 36 occurrences.
> > > "test-foo" has 33 occurrences.
> > >
> > > The things I am more concerned about is how this would affect file
> > > naming. If we have a unit test for foo.c, I think foo_test.c is more
> > > consistent with our namespacing conventions. The other thing, is if we
> > > already have a Kconfig symbol called FOO_TEST (or TEST_FOO) what
> > > should we name the KUnit test in this case? FOO_UNIT_TEST?
> > > FOO_KUNIT_TEST, like I did above?
> >
> > Ok, I can live with "foo-test", as you are right, in a directory listing
> > and config option, it makes more sense to add it as a suffix.
> 
> Cool, so just for future reference, if we already have a Kconfig
> symbol called FOO_TEST (or TEST_FOO) what should we name the KUnit
> test in this case? FOO_UNIT_TEST? FOO_KUNIT_TEST, like I did above?

FOO_KUNIT_TEST is fine, I doubt that's going to come up very often.

thanks,

greg k-h
diff mbox series

Patch

diff --git a/kernel/Makefile b/kernel/Makefile
index 6c57e78817dad..c81a8976b6a4b 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -112,6 +112,8 @@  obj-$(CONFIG_HAS_IOMEM) += iomem.o
 obj-$(CONFIG_ZONE_DEVICE) += memremap.o
 obj-$(CONFIG_RSEQ) += rseq.o
 
+obj-$(CONFIG_SYSCTL_KUNIT_TEST) += sysctl-test.o
+
 obj-$(CONFIG_GCC_PLUGIN_STACKLEAK) += stackleak.o
 KASAN_SANITIZE_stackleak.o := n
 KCOV_INSTRUMENT_stackleak.o := n
diff --git a/kernel/sysctl-test.c b/kernel/sysctl-test.c
new file mode 100644
index 0000000000000..a0fba6b6fc2dc
--- /dev/null
+++ b/kernel/sysctl-test.c
@@ -0,0 +1,292 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * KUnit test of proc sysctl.
+ */
+
+#include <kunit/test.h>
+#include <linux/printk.h>
+#include <linux/sysctl.h>
+#include <linux/uaccess.h>
+
+static int i_zero;
+static int i_one_hundred = 100;
+
+struct test_sysctl_data {
+	int int_0001;
+	int int_0002;
+	int int_0003[4];
+
+	unsigned int uint_0001;
+
+	char string_0001[65];
+};
+
+static struct test_sysctl_data test_data = {
+	.int_0001 = 60,
+	.int_0002 = 1,
+
+	.int_0003[0] = 0,
+	.int_0003[1] = 1,
+	.int_0003[2] = 2,
+	.int_0003[3] = 3,
+
+	.uint_0001 = 314,
+
+	.string_0001 = "(none)",
+};
+
+static void sysctl_test_dointvec_null_tbl_data(struct kunit *test)
+{
+	struct ctl_table table = {
+		.procname = "foo",
+		.data		= NULL,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec,
+		.extra1		= &i_zero,
+		.extra2         = &i_one_hundred,
+	};
+	void  *buffer = kunit_kzalloc(test, sizeof(int), GFP_USER);
+	size_t len;
+	loff_t pos;
+
+	len = 1234;
+	KUNIT_EXPECT_EQ(test, 0, proc_dointvec(&table, 0, buffer, &len, &pos));
+	KUNIT_EXPECT_EQ(test, 0, len);
+	len = 1234;
+	KUNIT_EXPECT_EQ(test, 0, proc_dointvec(&table, 1, buffer, &len, &pos));
+	KUNIT_EXPECT_EQ(test, 0, len);
+}
+
+static void sysctl_test_dointvec_table_maxlen_unset(struct kunit *test)
+{
+	struct ctl_table table = {
+		.procname = "foo",
+		.data		= &test_data.int_0001,
+		.maxlen		= 0,
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec,
+		.extra1		= &i_zero,
+		.extra2         = &i_one_hundred,
+	};
+	void  *buffer = kunit_kzalloc(test, sizeof(int), GFP_USER);
+	size_t len;
+	loff_t pos;
+
+	len = 1234;
+	KUNIT_EXPECT_EQ(test, 0, proc_dointvec(&table, 0, buffer, &len, &pos));
+	KUNIT_EXPECT_EQ(test, 0, len);
+	len = 1234;
+	KUNIT_EXPECT_EQ(test, 0, proc_dointvec(&table, 1, buffer, &len, &pos));
+	KUNIT_EXPECT_EQ(test, 0, len);
+}
+
+static void sysctl_test_dointvec_table_len_is_zero(struct kunit *test)
+{
+	struct ctl_table table = {
+		.procname = "foo",
+		.data		= &test_data.int_0001,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec,
+		.extra1		= &i_zero,
+		.extra2         = &i_one_hundred,
+	};
+	void  *buffer = kunit_kzalloc(test, sizeof(int), GFP_USER);
+	size_t len;
+	loff_t pos;
+
+	len = 0;
+	KUNIT_EXPECT_EQ(test, 0, proc_dointvec(&table, 0, buffer, &len, &pos));
+	KUNIT_EXPECT_EQ(test, 0, len);
+	KUNIT_EXPECT_EQ(test, 0, proc_dointvec(&table, 1, buffer, &len, &pos));
+	KUNIT_EXPECT_EQ(test, 0, len);
+}
+
+static void sysctl_test_dointvec_table_read_but_position_set(struct kunit *test)
+{
+	struct ctl_table table = {
+		.procname = "foo",
+		.data		= &test_data.int_0001,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec,
+		.extra1		= &i_zero,
+		.extra2         = &i_one_hundred,
+	};
+	void  *buffer = kunit_kzalloc(test, sizeof(int), GFP_USER);
+	size_t len;
+	loff_t pos;
+
+	len = 1234;
+	pos = 1;
+	KUNIT_EXPECT_EQ(test, 0, proc_dointvec(&table, 0, buffer, &len, &pos));
+	KUNIT_EXPECT_EQ(test, 0, len);
+}
+
+static void sysctl_test_dointvec_happy_single_positive(struct kunit *test)
+{
+	struct ctl_table table = {
+		.procname = "foo",
+		.data		= &test_data.int_0001,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec,
+		.extra1		= &i_zero,
+		.extra2         = &i_one_hundred,
+	};
+	char input[] = "9";
+	size_t len = sizeof(input) - 1;
+	loff_t pos = 0;
+
+	table.data = kunit_kzalloc(test, sizeof(int), GFP_USER);
+	KUNIT_EXPECT_EQ(test, 0, proc_dointvec(&table, 1, input, &len, &pos));
+	KUNIT_EXPECT_EQ(test, sizeof(input) - 1, len);
+	KUNIT_EXPECT_EQ(test, sizeof(input) - 1, pos);
+	KUNIT_EXPECT_EQ(test, 9, *(int *)table.data);
+}
+
+static void sysctl_test_dointvec_happy_single_negative(struct kunit *test)
+{
+	struct ctl_table table = {
+		.procname = "foo",
+		.data		= &test_data.int_0001,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec,
+		.extra1		= &i_zero,
+		.extra2         = &i_one_hundred,
+	};
+	char input[] = "-9";
+	size_t len = sizeof(input) - 1;
+	loff_t pos = 0;
+
+	table.data = kunit_kzalloc(test, sizeof(int), GFP_USER);
+	KUNIT_EXPECT_EQ(test, 0, proc_dointvec(&table, 1, input, &len, &pos));
+	KUNIT_EXPECT_EQ(test, sizeof(input) - 1, len);
+	KUNIT_EXPECT_EQ(test, sizeof(input) - 1, pos);
+	KUNIT_EXPECT_EQ(test, -9, *(int *)table.data);
+}
+
+static void sysctl_test_dointvec_single_less_int_min(struct kunit *test)
+{
+	struct ctl_table table = {
+		.procname = "foo",
+		.data		= &test_data.int_0001,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec,
+		.extra1		= &i_zero,
+		.extra2         = &i_one_hundred,
+	};
+	char input[32];
+	size_t len = sizeof(input) - 1;
+	loff_t pos = 0;
+	long less_than_min = (long)INT_MIN - 1;
+
+	KUNIT_EXPECT_LT(test, less_than_min, INT_MIN);
+	KUNIT_EXPECT_LT(test,
+			snprintf(input, sizeof(input), "%ld", less_than_min),
+			sizeof(input));
+
+	table.data = kunit_kzalloc(test, sizeof(int), GFP_USER);
+	KUNIT_EXPECT_EQ(test, -EINVAL,
+			proc_dointvec(&table, 1, input, &len, &pos));
+	KUNIT_EXPECT_EQ(test, sizeof(input) - 1, len);
+	KUNIT_EXPECT_EQ(test, 0, *(int *)table.data);
+}
+
+static void sysctl_test_dointvec_single_greater_int_max(struct kunit *test)
+{
+	struct ctl_table table = {
+		.procname = "foo",
+		.data		= &test_data.int_0001,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec,
+		.extra1		= &i_zero,
+		.extra2         = &i_one_hundred,
+	};
+	char input[32];
+	size_t len = sizeof(input) - 1;
+	loff_t pos = 0;
+	long greater_than_max = (long)INT_MAX + 1;
+
+	KUNIT_EXPECT_GT(test, greater_than_max, INT_MAX);
+	KUNIT_EXPECT_LT(test, snprintf(input, sizeof(input), "%ld",
+				       greater_than_max),
+			sizeof(input));
+	table.data = kunit_kzalloc(test, sizeof(int), GFP_USER);
+	KUNIT_EXPECT_EQ(test, -EINVAL,
+			proc_dointvec(&table, 1, input, &len, &pos));
+	KUNIT_EXPECT_EQ(test, sizeof(input) - 1, len);
+	KUNIT_EXPECT_EQ(test, 0, *(int *)table.data);
+}
+
+static int sysctl_test_init(struct kunit *test)
+{
+	return 0;
+}
+
+/*
+ * This is run once after each test case, see the comment on example_test_module
+ * for more information.
+ */
+static void sysctl_test_exit(struct kunit *test)
+{
+}
+
+/*
+ * Here we make a list of all the test cases we want to add to the test module
+ * below.
+ */
+static struct kunit_case sysctl_test_cases[] = {
+	/*
+	 * This is a helper to create a test case object from a test case
+	 * function; its exact function is not important to understand how to
+	 * use KUnit, just know that this is how you associate test cases with a
+	 * test module.
+	 */
+	KUNIT_CASE(sysctl_test_dointvec_null_tbl_data),
+	KUNIT_CASE(sysctl_test_dointvec_table_maxlen_unset),
+	KUNIT_CASE(sysctl_test_dointvec_table_len_is_zero),
+	KUNIT_CASE(sysctl_test_dointvec_table_read_but_position_set),
+	KUNIT_CASE(sysctl_test_dointvec_happy_single_positive),
+	KUNIT_CASE(sysctl_test_dointvec_happy_single_negative),
+	KUNIT_CASE(sysctl_test_dointvec_single_less_int_min),
+	KUNIT_CASE(sysctl_test_dointvec_single_greater_int_max),
+	{},
+};
+
+/*
+ * This defines a suite or grouping of tests.
+ *
+ * Test cases are defined as belonging to the suite by adding them to
+ * `test_cases`.
+ *
+ * Often it is desirable to run some function which will set up things which
+ * will be used by every test; this is accomplished with an `init` function
+ * which runs before each test case is invoked. Similarly, an `exit` function
+ * may be specified which runs after every test case and can be used to for
+ * cleanup. For clarity, running tests in a test module would behave as follows:
+ *
+ * module.init(test);
+ * module.test_case[0](test);
+ * module.exit(test);
+ * module.init(test);
+ * module.test_case[1](test);
+ * module.exit(test);
+ * ...;
+ */
+static struct kunit_module sysctl_test_module = {
+	.name = "sysctl_test",
+	.init = sysctl_test_init,
+	.exit = sysctl_test_exit,
+	.test_cases = sysctl_test_cases,
+};
+
+/*
+ * This registers the above test module telling KUnit that this is a suite of
+ * tests that need to be run.
+ */
+module_test(sysctl_test_module);
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index d5a4a4036d2f8..772af4ec70111 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1908,6 +1908,12 @@  config TEST_SYSCTL
 
 	  If unsure, say N.
 
+config SYSCTL_KUNIT_TEST
+	bool "KUnit test for sysctl"
+	depends on KUNIT
+	help
+	  Enables KUnit sysctl test.
+
 config TEST_UDELAY
 	tristate "udelay test driver"
 	help