lib/test_kmod: add missing MODULE_DESCRIPTION() macro

make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/test_kmod.o

Add the missing invocation of the

lib/test_kmod: add missing MODULE_DESCRIPTION() macro

make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/test_kmod.o

Add the missing invocation of the MODULE_DESCRIPTION() macro.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Jeff Johnson <[email protected]>
Reviewed-by: Lucas De Marchi <[email protected]>
Cc: Luis Chamberlain <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

show more ...

lib/test_kmod: fix kernel-doc warnings

Fix all kernel-doc warnings in test_kmod.c:
- Mark some enum values as private so that kernel-doc is not needed
for them
- s/thread_mutex/thread_lock/ in a s

lib/test_kmod: fix kernel-doc warnings

Fix all kernel-doc warnings in test_kmod.c:
- Mark some enum values as private so that kernel-doc is not needed
for them
- s/thread_mutex/thread_lock/ in a struct's kernel-doc comments
- add kernel-doc info for @task_sync

test_kmod.c:67: warning: Enum value '__TEST_KMOD_INVALID' not described in enum 'kmod_test_case'
test_kmod.c:67: warning: Enum value '__TEST_KMOD_MAX' not described in enum 'kmod_test_case'
test_kmod.c:100: warning: Function parameter or member 'task_sync' not described in 'kmod_test_device_info'
test_kmod.c:134: warning: Function parameter or member 'thread_mutex' not described in 'kmod_test_device'

Signed-off-by: Randy Dunlap <[email protected]>
Cc: Luis Chamberlain <[email protected]>
Cc: <[email protected]>
Signed-off-by: Luis Chamberlain <[email protected]>

show more ...

test_kmod: stop kernel-doc warnings

Use kernel-doc notation to prevent warnings:

lib/test_kmod.c:58: warning: contents before sections
lib/test_kmod.c:94: warning: cannot understand function protot

test_kmod: stop kernel-doc warnings

Use kernel-doc notation to prevent warnings:

lib/test_kmod.c:58: warning: contents before sections
lib/test_kmod.c:94: warning: cannot understand function prototype: 'struct kmod_test_device_info '
lib/test_kmod.c:119: warning: cannot understand function prototype: 'struct kmod_test_device '

Signed-off-by: Randy Dunlap <[email protected]>
Cc: Luis Chamberlain <[email protected]>
Cc: [email protected]
Signed-off-by: Luis Chamberlain <[email protected]>

show more ...

testing: use the copyleft-next-0.3.1 SPDX tag

Two selftests drivers exist under the copyleft-next license.
These drivers were added prior to SPDX practice taking full swing
in the kernel. Now that w

testing: use the copyleft-next-0.3.1 SPDX tag

Two selftests drivers exist under the copyleft-next license.
These drivers were added prior to SPDX practice taking full swing
in the kernel. Now that we have an SPDX tag for copyleft-next-0.3.1
documented, embrace it and remove the boiler plate.

Cc: Goldwyn Rodrigues <[email protected]>
Cc: Kuno Woudt <[email protected]>
Cc: Richard Fontana <[email protected]>
Cc: [email protected]
Cc: Ciaran Farrell <[email protected]>
Cc: Christopher De Nicolo <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Cc: Thorsten Leemhuis <[email protected]>
Cc: Andrew Morton <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Signed-off-by: Luis Chamberlain <[email protected]>
Reviewed-by: Tim Bird <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

lib/test: use after free in register_test_dev_kmod()

The "test_dev" pointer is freed but then returned to the caller.

Fixes: d9c6a72d6fa2 ("kmod: add test driver to stress test the module loader")

lib/test: use after free in register_test_dev_kmod()

The "test_dev" pointer is freed but then returned to the caller.

Fixes: d9c6a72d6fa2 ("kmod: add test driver to stress test the module loader")
Signed-off-by: Dan Carpenter <[email protected]>
Signed-off-by: Luis Chamberlain <[email protected]>

show more ...

lib/test: fix spelling mistakes

Fix some spelling mistakes in comments found by "codespell":
thats ==> that's
unitialized ==> uninitialized
panicing ==> panicking
sucess ==> success
possitive ==> po

lib/test: fix spelling mistakes

Fix some spelling mistakes in comments found by "codespell":
thats ==> that's
unitialized ==> uninitialized
panicing ==> panicking
sucess ==> success
possitive ==> positive
intepreted ==> interpreted

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Zhen Lei <[email protected]>
Acked-by: Yonghong Song <[email protected]> [test_bfp.c]
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

lib: cleanup kstrto*() usage

Use proper conversion functions. kstrto*() variants exist for all
standard types.

Link: https://lkml.kernel.org/r/[email protected]
Signed-o

lib: cleanup kstrto*() usage

Use proper conversion functions. kstrto*() variants exist for all
standard types.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Alexey Dobriyan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

test_kmod: avoid potential double free in trigger_config_run_type()

Reset the member "test_fs" of the test configuration after a call of the
function "kfree_const" to a null pointer so that a double

test_kmod: avoid potential double free in trigger_config_run_type()

Reset the member "test_fs" of the test configuration after a call of the
function "kfree_const" to a null pointer so that a double memory release
will not be performed.

Fixes: d9c6a72d6fa2 ("kmod: add test driver to stress test the module loader")
Signed-off-by: Tiezhu Yang <[email protected]>
Signed-off-by: Luis Chamberlain <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Acked-by: Luis Chamberlain <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Al Viro <[email protected]>
Cc: Christian Brauner <[email protected]>
Cc: Chuck Lever <[email protected]>
Cc: David Howells <[email protected]>
Cc: David S. Miller <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Jakub Kicinski <[email protected]>
Cc: James Morris <[email protected]>
Cc: Jarkko Sakkinen <[email protected]>
Cc: J. Bruce Fields <[email protected]>
Cc: Jens Axboe <[email protected]>
Cc: Josh Triplett <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Lars Ellenberg <[email protected]>
Cc: Nikolay Aleksandrov <[email protected]>
Cc: Philipp Reisner <[email protected]>
Cc: Roopa Prabhu <[email protected]>
Cc: "Serge E. Hallyn" <[email protected]>
Cc: Sergei Trofimovich <[email protected]>
Cc: Sergey Kvachonok <[email protected]>
Cc: Shuah Khan <[email protected]>
Cc: Tony Vroon <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

lib/test_kmod.c: remove a NULL test

The "info" pointer has already been dereferenced so checking here is too
late. Fortunately, we never pass NULL pointers to the
test_kmod_put_module() function so

lib/test_kmod.c: remove a NULL test

The "info" pointer has already been dereferenced so checking here is too
late. Fortunately, we never pass NULL pointers to the
test_kmod_put_module() function so the test can simply be removed.

Signed-off-by: Dan Carpenter <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Acked-by: Luis Chamberlain <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

lib/test_kmod.c: potential double free in error handling

There is a copy and paste bug so we set "config->test_driver" to NULL
twice instead of setting "config->test_fs". Smatch complains that it
l

lib/test_kmod.c: potential double free in error handling

There is a copy and paste bug so we set "config->test_driver" to NULL
twice instead of setting "config->test_fs". Smatch complains that it
leads to a double free:

lib/test_kmod.c:840 __kmod_config_init() warn: 'config->test_fs' double freed

Link: http://lkml.kernel.org/r/20190121140011.GA14283@kadam
Fixes: d9c6a72d6fa2 ("kmod: add test driver to stress test the module loader")
Signed-off-by: Dan Carpenter <[email protected]>
Acked-by: Luis Chamberlain <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

lib/test_kmod.c: fix rmmod double free

We free the misc device string twice on rmmod; fix this. Without this
we cannot remove the module without crashing.

Link: http://lkml.kernel.org/r/2018112405

lib/test_kmod.c: fix rmmod double free

We free the misc device string twice on rmmod; fix this. Without this
we cannot remove the module without crashing.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Luis Chamberlain <[email protected]>
Reported-by: Randy Dunlap <[email protected]>
Reviewed-by: Andrew Morton <[email protected]>
Cc: <[email protected]> [4.12+]
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

treewide: Use array_size() in vzalloc()

The vzalloc() function has no 2-factor argument form, so multiplication
factors need to be wrapped in array_size(). This patch replaces cases of:

vza

treewide: Use array_size() in vzalloc()

The vzalloc() function has no 2-factor argument form, so multiplication
factors need to be wrapped in array_size(). This patch replaces cases of:

vzalloc(a * b)

with:
vzalloc(array_size(a, b))

as well as handling cases of:

vzalloc(a * b * c)

with:

vzalloc(array3_size(a, b, c))

This does, however, attempt to ignore constant size factors like:

vzalloc(4 * 1024)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
vzalloc(
- (sizeof(TYPE)) * E
+ sizeof(TYPE) * E
, ...)
|
vzalloc(
- (sizeof(THING)) * E
+ sizeof(THING) * E
, ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
vzalloc(
- sizeof(u8) * (COUNT)
+ COUNT
, ...)
|
vzalloc(
- sizeof(__u8) * (COUNT)
+ COUNT
, ...)
|
vzalloc(
- sizeof(char) * (COUNT)
+ COUNT
, ...)
|
vzalloc(
- sizeof(unsigned char) * (COUNT)
+ COUNT
, ...)
|
vzalloc(
- sizeof(u8) * COUNT
+ COUNT
, ...)
|
vzalloc(
- sizeof(__u8) * COUNT
+ COUNT
, ...)
|
vzalloc(
- sizeof(char) * COUNT
+ COUNT
, ...)
|
vzalloc(
- sizeof(unsigned char) * COUNT
+ COUNT
, ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
vzalloc(
- sizeof(TYPE) * (COUNT_ID)
+ array_size(COUNT_ID, sizeof(TYPE))
, ...)
|
vzalloc(
- sizeof(TYPE) * COUNT_ID
+ array_size(COUNT_ID, sizeof(TYPE))
, ...)
|
vzalloc(
- sizeof(TYPE) * (COUNT_CONST)
+ array_size(COUNT_CONST, sizeof(TYPE))
, ...)
|
vzalloc(
- sizeof(TYPE) * COUNT_CONST
+ array_size(COUNT_CONST, sizeof(TYPE))
, ...)
|
vzalloc(
- sizeof(THING) * (COUNT_ID)
+ array_size(COUNT_ID, sizeof(THING))
, ...)
|
vzalloc(
- sizeof(THING) * COUNT_ID
+ array_size(COUNT_ID, sizeof(THING))
, ...)
|
vzalloc(
- sizeof(THING) * (COUNT_CONST)
+ array_size(COUNT_CONST, sizeof(THING))
, ...)
|
vzalloc(
- sizeof(THING) * COUNT_CONST
+ array_size(COUNT_CONST, sizeof(THING))
, ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

vzalloc(
- SIZE * COUNT
+ array_size(COUNT, SIZE)
, ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
vzalloc(
- sizeof(TYPE) * (COUNT) * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
vzalloc(
- sizeof(TYPE) * (COUNT) * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
vzalloc(
- sizeof(TYPE) * COUNT * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
vzalloc(
- sizeof(TYPE) * COUNT * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
vzalloc(
- sizeof(THING) * (COUNT) * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
vzalloc(
- sizeof(THING) * (COUNT) * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
vzalloc(
- sizeof(THING) * COUNT * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
vzalloc(
- sizeof(THING) * COUNT * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
vzalloc(
- sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+ array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
, ...)
|
vzalloc(
- sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
, ...)
|
vzalloc(
- sizeof(THING1) * sizeof(THING2) * COUNT
+ array3_size(COUNT, sizeof(THING1), sizeof(THING2))
, ...)
|
vzalloc(
- sizeof(THING1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(THING1), sizeof(THING2))
, ...)
|
vzalloc(
- sizeof(TYPE1) * sizeof(THING2) * COUNT
+ array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
, ...)
|
vzalloc(
- sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
, ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
vzalloc(
- (COUNT) * STRIDE * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
vzalloc(
- COUNT * (STRIDE) * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
vzalloc(
- COUNT * STRIDE * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
vzalloc(
- (COUNT) * (STRIDE) * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
vzalloc(
- COUNT * (STRIDE) * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
vzalloc(
- (COUNT) * STRIDE * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
vzalloc(
- (COUNT) * (STRIDE) * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
vzalloc(
- COUNT * STRIDE * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
)

// Any remaining multi-factor products, first at least 3-factor products
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
vzalloc(C1 * C2 * C3, ...)
|
vzalloc(
- E1 * E2 * E3
+ array3_size(E1, E2, E3)
, ...)
)

// And then all remaining 2 factors products when they're not all constants.
@@
expression E1, E2;
constant C1, C2;
@@

(
vzalloc(C1 * C2, ...)
|
vzalloc(
- E1 * E2
+ array_size(E1, E2)
, ...)
)

Signed-off-by: Kees Cook <[email protected]>

show more ...

lib/test_kmod.c: fix limit check on number of test devices created

As reported by Dan the parentheses is in the wrong place, and since
unlikely() call returns either 0 or 1 it's never less than zero

lib/test_kmod.c: fix limit check on number of test devices created

As reported by Dan the parentheses is in the wrong place, and since
unlikely() call returns either 0 or 1 it's never less than zero. The
second issue is that signed integer overflows like "INT_MAX + 1" are
undefined behavior.

Since num_test_devs represents the number of devices, we want to stop
prior to hitting the max, and not rely on the wrap arround at all. So
just cap at num_test_devs + 1, prior to assigning a new device.

Link: http://lkml.kernel.org/r/[email protected]
Fixes: d9c6a72d6fa2 ("kmod: add test driver to stress test the module loader")
Reported-by: Dan Carpenter <[email protected]>
Signed-off-by: Luis R. Rodriguez <[email protected]>
Acked-by: Kees Cook <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

treewide: Use DEVICE_ATTR_RW

Convert DEVICE_ATTR uses to DEVICE_ATTR_RW where possible.

Done with perl script:

$ git grep -w --name-only DEVICE_ATTR | \
xargs perl -i -e 'local $/; while (<>) {

treewide: Use DEVICE_ATTR_RW

Convert DEVICE_ATTR uses to DEVICE_ATTR_RW where possible.

Done with perl script:

$ git grep -w --name-only DEVICE_ATTR | \
xargs perl -i -e 'local $/; while (<>) { s/\bDEVICE_ATTR\s*\(\s*(\w+)\s*,\s*\(?(\s*S_IRUGO\s*\|\s*S_IWUSR|\s*S_IWUSR\s*\|\s*S_IRUGO\s*|\s*0644\s*)\)?\s*,\s*\1_show\s*,\s*\1_store\s*\)/DEVICE_ATTR_RW(\1)/g; print;}'

Signed-off-by: Joe Perches <[email protected]>
Acked-by: Felipe Balbi <[email protected]>
Acked-by: Andy Shevchenko <[email protected]>
Acked-by: Bartlomiej Zolnierkiewicz <[email protected]>
Acked-by: Zhang Rui <[email protected]>
Acked-by: Jarkko Nikula <[email protected]>
Acked-by: Jani Nikula <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

show more ...

lib/test: delete five error messages for failed memory allocations

Omit extra messages for a memory allocation failure in these functions.

This issue was detected by using the Coccinelle software.

lib/test: delete five error messages for failed memory allocations

Omit extra messages for a memory allocation failure in these functions.

This issue was detected by using the Coccinelle software.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Markus Elfring <[email protected]>
Acked-by: Michal Hocko <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

test_kmod: flip INT checks to be consistent

Most checks will check for min and then max, except the int check. Flip
the checks to be consistent with the other code.

[[email protected]: massaged co

test_kmod: flip INT checks to be consistent

Most checks will check for min and then max, except the int check. Flip
the checks to be consistent with the other code.

[[email protected]: massaged commit log]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Dan Carpenter <[email protected]>
Signed-off-by: Luis R. Rodriguez <[email protected]>
Cc: Dmitry Torokhov <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Jessica Yu <[email protected]>
Cc: Rusty Russell <[email protected]>
Cc: Michal Marek <[email protected]>
Cc: Petr Mladek <[email protected]>
Cc: Miroslav Benes <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Eric W. Biederman <[email protected]>
Cc: Shuah Khan <[email protected]>
Cc: Colin Ian King <[email protected]>
Cc: David Binderman <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

test_kmod: remove paranoid UINT_MAX check on uint range processing

The UINT_MAX comparison is not needed because "max" is already an unsigned
int, and we expect developer C code max value input to h

test_kmod: remove paranoid UINT_MAX check on uint range processing

The UINT_MAX comparison is not needed because "max" is already an unsigned
int, and we expect developer C code max value input to have a sensible 0 -
UINT_MAX range. Note that if it so happens to be UINT_MAX + 1 it would
lead to an issue, but we expect the developer to know this.

[[email protected]: massaged commit log]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Dan Carpenter <[email protected]>
Signed-off-by: Luis R. Rodriguez <[email protected]>
Cc: Dmitry Torokhov <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Jessica Yu <[email protected]>
Cc: Rusty Russell <[email protected]>
Cc: Michal Marek <[email protected]>
Cc: Petr Mladek <[email protected]>
Cc: Miroslav Benes <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Eric W. Biederman <[email protected]>
Cc: Shuah Khan <[email protected]>
Cc: Colin Ian King <[email protected]>
Cc: David Binderman <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

test_kmod: fix small memory leak on filesystem tests

The break was in the wrong place so file system tests don't work as
intended, leaking memory at each test switch.

[[email protected]: massaged c

test_kmod: fix small memory leak on filesystem tests

The break was in the wrong place so file system tests don't work as
intended, leaking memory at each test switch.

[[email protected]: massaged commit subject, noted memory leak issue without the fix]
Link: http://lkml.kernel.org/r/[email protected]
Fixes: 39258f448d71 ("kmod: add test driver to stress test the module loader")
Signed-off-by: Dan Carpenter <[email protected]>
Signed-off-by: Luis R. Rodriguez <[email protected]>
Reported-by: David Binderman <[email protected]>
Cc: Colin Ian King <[email protected]>
Cc: Dmitry Torokhov <[email protected]>
Cc: Eric W. Biederman <[email protected]>
Cc: Jessica Yu <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Michal Marek <[email protected]>
Cc: Miroslav Benes <[email protected]>
Cc: Petr Mladek <[email protected]>
Cc: Rusty Russell <[email protected]>
Cc: Shuah Khan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

test_kmod: fix the lock in register_test_dev_kmod()

We accidentally just drop the lock twice instead of taking it and then
releasing it. This isn't a big issue unless you are adding more than
one d

test_kmod: fix the lock in register_test_dev_kmod()

We accidentally just drop the lock twice instead of taking it and then
releasing it. This isn't a big issue unless you are adding more than
one device to test on, and the kmod.sh doesn't do that yet, however this
obviously is the correct thing to do.

[[email protected]: massaged subject, explain what happens]
Link: http://lkml.kernel.org/r/[email protected]
Fixes: 39258f448d71 ("kmod: add test driver to stress test the module loader")
Signed-off-by: Dan Carpenter <[email protected]>
Signed-off-by: Luis R. Rodriguez <[email protected]>
Cc: Colin Ian King <[email protected]>
Cc: David Binderman <[email protected]>
Cc: Dmitry Torokhov <[email protected]>
Cc: Eric W. Biederman <[email protected]>
Cc: Jessica Yu <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Michal Marek <[email protected]>
Cc: Miroslav Benes <[email protected]>
Cc: Petr Mladek <[email protected]>
Cc: Rusty Russell <[email protected]>
Cc: Shuah Khan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

test_kmod: fix bug which allows negative values on two config options

Parsing with kstrtol() enables values to be negative, and we failed to
check for negative values when parsing with test_dev_conf

test_kmod: fix bug which allows negative values on two config options

Parsing with kstrtol() enables values to be negative, and we failed to
check for negative values when parsing with test_dev_config_update_uint_sync()
or test_dev_config_update_uint_range().

test_dev_config_update_uint_range() has a minimum check though so an
issue is not present there. test_dev_config_update_uint_sync() is only
used for the number of threads to use (config_num_threads_store()), and
indeed this would fail with an attempt for a large allocation.

Although the issue is only present in practice with the first fix both
by using kstrtoul() instead of kstrtol().

Link: http://lkml.kernel.org/r/[email protected]
Fixes: 39258f448d71 ("kmod: add test driver to stress test the module loader")
Signed-off-by: Luis R. Rodriguez <[email protected]>
Reported-by: Dan Carpenter <[email protected]>
Cc: Colin Ian King <[email protected]>
Cc: David Binderman <[email protected]>
Cc: Dmitry Torokhov <[email protected]>
Cc: Eric W. Biederman <[email protected]>
Cc: Jessica Yu <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Michal Marek <[email protected]>
Cc: Miroslav Benes <[email protected]>
Cc: Petr Mladek <[email protected]>
Cc: Rusty Russell <[email protected]>
Cc: Shuah Khan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

test_kmod: fix spelling mistake: "EMTPY" -> "EMPTY"

Trivial fix to spelling mistake in snprintf text

[[email protected]: massaged commit message]
Link: http://lkml.kernel.org/r/20170802211450.27928

test_kmod: fix spelling mistake: "EMTPY" -> "EMPTY"

Trivial fix to spelling mistake in snprintf text

[[email protected]: massaged commit message]
Link: http://lkml.kernel.org/r/[email protected]
Fixes: 39258f448d71 ("kmod: add test driver to stress test the module loader")
Signed-off-by: Colin Ian King <[email protected]>
Signed-off-by: Luis R. Rodriguez <[email protected]>
Cc: Dmitry Torokhov <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Jessica Yu <[email protected]>
Cc: Rusty Russell <[email protected]>
Cc: Michal Marek <[email protected]>
Cc: Petr Mladek <[email protected]>
Cc: Miroslav Benes <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Eric W. Biederman <[email protected]>
Cc: Shuah Khan <[email protected]>
Cc: Dan Carpenter <[email protected]>
Cc: David Binderman <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

kmod: add test driver to stress test the module loader

This adds a new stress test driver for kmod: the kernel module loader.
The new stress test driver, test_kmod, is only enabled as a module right

kmod: add test driver to stress test the module loader

This adds a new stress test driver for kmod: the kernel module loader.
The new stress test driver, test_kmod, is only enabled as a module right
now. It should be possible to load this as built-in and load tests
early (refer to the force_init_test module parameter), however since a
lot of test can get a system out of memory fast we leave this disabled
for now.

Using a system with 1024 MiB of RAM can *easily* get your kernel OOM
fast with this test driver.

The test_kmod driver exposes API knobs for us to fine tune simple
request_module() and get_fs_type() calls. Since these API calls only
allow each one parameter a test driver for these is rather simple.
Other factors that can help out test driver though are the number of
calls we issue and knowing current limitations of each. This exposes
configuration as much as possible through userspace to be able to build
tests directly from userspace.

Since it allows multiple misc devices its will eventually (once we add a
knob to let us create new devices at will) also be possible to perform
more tests in parallel, provided you have enough memory.

We only enable tests we know work as of right now.

Demo screenshots:

# tools/testing/selftests/kmod/kmod.sh
kmod_test_0001_driver: OK! - loading kmod test
kmod_test_0001_driver: OK! - Return value: 256 (MODULE_NOT_FOUND), expected MODULE_NOT_FOUND
kmod_test_0001_fs: OK! - loading kmod test
kmod_test_0001_fs: OK! - Return value: -22 (-EINVAL), expected -EINVAL
kmod_test_0002_driver: OK! - loading kmod test
kmod_test_0002_driver: OK! - Return value: 256 (MODULE_NOT_FOUND), expected MODULE_NOT_FOUND
kmod_test_0002_fs: OK! - loading kmod test
kmod_test_0002_fs: OK! - Return value: -22 (-EINVAL), expected -EINVAL
kmod_test_0003: OK! - loading kmod test
kmod_test_0003: OK! - Return value: 0 (SUCCESS), expected SUCCESS
kmod_test_0004: OK! - loading kmod test
kmod_test_0004: OK! - Return value: 0 (SUCCESS), expected SUCCESS
kmod_test_0005: OK! - loading kmod test
kmod_test_0005: OK! - Return value: 0 (SUCCESS), expected SUCCESS
kmod_test_0006: OK! - loading kmod test
kmod_test_0006: OK! - Return value: 0 (SUCCESS), expected SUCCESS
kmod_test_0005: OK! - loading kmod test
kmod_test_0005: OK! - Return value: 0 (SUCCESS), expected SUCCESS
kmod_test_0006: OK! - loading kmod test
kmod_test_0006: OK! - Return value: 0 (SUCCESS), expected SUCCESS
XXX: add test restult for 0007
Test completed

You can also request for specific tests:

# tools/testing/selftests/kmod/kmod.sh -t 0001
kmod_test_0001_driver: OK! - loading kmod test
kmod_test_0001_driver: OK! - Return value: 256 (MODULE_NOT_FOUND), expected MODULE_NOT_FOUND
kmod_test_0001_fs: OK! - loading kmod test
kmod_test_0001_fs: OK! - Return value: -22 (-EINVAL), expected -EINVAL
Test completed

Lastly, the current available number of tests:

# tools/testing/selftests/kmod/kmod.sh --help
Usage: tools/testing/selftests/kmod/kmod.sh [ -t <4-number-digit> ]
Valid tests: 0001-0009

0001 - Simple test - 1 thread for empty string
0002 - Simple test - 1 thread for modules/filesystems that do not exist
0003 - Simple test - 1 thread for get_fs_type() only
0004 - Simple test - 2 threads for get_fs_type() only
0005 - multithreaded tests with default setup - request_module() only
0006 - multithreaded tests with default setup - get_fs_type() only
0007 - multithreaded tests with default setup test request_module() and get_fs_type()
0008 - multithreaded - push kmod_concurrent over max_modprobes for request_module()
0009 - multithreaded - push kmod_concurrent over max_modprobes for get_fs_type()

The following test cases currently fail, as such they are not currently
enabled by default:

# tools/testing/selftests/kmod/kmod.sh -t 0008
# tools/testing/selftests/kmod/kmod.sh -t 0009

To be sure to run them as intended please unload both of the modules:

o test_module
o xfs

And ensure they are not loaded on your system prior to testing them. If
you use these paritions for your rootfs you can change the default test
driver used for get_fs_type() by exporting it into your environment. For
example of other test defaults you can override refer to kmod.sh
allow_user_defaults().

Behind the scenes this is how we fine tune at a test case prior to
hitting a trigger to run it:

cat /sys/devices/virtual/misc/test_kmod0/config
echo -n "2" > /sys/devices/virtual/misc/test_kmod0/config_test_case
echo -n "ext4" > /sys/devices/virtual/misc/test_kmod0/config_test_fs
echo -n "80" > /sys/devices/virtual/misc/test_kmod0/config_num_threads
cat /sys/devices/virtual/misc/test_kmod0/config
echo -n "1" > /sys/devices/virtual/misc/test_kmod0/config_num_threads

Finally to trigger:

echo -n "1" > /sys/devices/virtual/misc/test_kmod0/trigger_config

The kmod.sh script uses the above constructs to build different test cases.

A bit of interpretation of the current failures follows, first two
premises:

a) When request_module() is used userspace figures out an optimized
version of module order for us. Once it finds the modules it needs, as
per depmod symbol dep map, it will finit_module() the respective
modules which are needed for the original request_module() request.

b) We have an optimization in place whereby if a kernel uses
request_module() on a module already loaded we never bother userspace
as the module already is loaded. This is all handled by kernel/kmod.c.

A few things to consider to help identify root causes of issues:

0) kmod 19 has a broken heuristic for modules being assumed to be
built-in to your kernel and will return 0 even though request_module()
failed. Upgrade to a newer version of kmod.

1) A get_fs_type() call for "xfs" will request_module() for "fs-xfs",
not for "xfs". The optimization in kernel described in b) fails to
catch if we have a lot of consecutive get_fs_type() calls. The reason
is the optimization in place does not look for aliases. This means two
consecutive get_fs_type() calls will bump kmod_concurrent, whereas
request_module() will not.

This one explanation why test case 0009 fails at least once for
get_fs_type().

2) If a module fails to load --- for whatever reason (kmod_concurrent
limit reached, file not yet present due to rootfs switch, out of
memory) we have a period of time during which module request for the
same name either with request_module() or get_fs_type() will *also*
fail to load even if the file for the module is ready.

This explains why *multiple* NULLs are possible on test 0009.

3) finit_module() consumes quite a bit of memory.

4) Filesystems typically also have more dependent modules than other
modules, its important to note though that even though a get_fs_type()
call does not incur additional kmod_concurrent bumps, since userspace
loads dependencies it finds it needs via finit_module_fd(), it *will*
take much more memory to load a module with a lot of dependencies.

Because of 3) and 4) we will easily run into out of memory failures with
certain tests. For instance test 0006 fails on qemu with 1024 MiB of RAM.
It panics a box after reaping all userspace processes and still not
having enough memory to reap.

[[email protected]: add dependencies for test module]
Link: http://lkml.kernel.org/r/[email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Luis R. Rodriguez <[email protected]>
Cc: Jessica Yu <[email protected]>
Cc: Shuah Khan <[email protected]>
Cc: Rusty Russell <[email protected]>
Cc: Michal Marek <[email protected]>
Cc: Petr Mladek <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...