Commit Graph

7 Commits

Author SHA1 Message Date
Kees Cook 8e060c21ae lib/test_overflow.c: avoid tainting the kernel and fix wrap size
This adds __GFP_NOWARN to the kmalloc()-portions of the overflow test to
avoid tainting the kernel.  Additionally fixes up the math on wrap size
to be architecture and page size agnostic.

Link: http://lkml.kernel.org/r/201905282012.0A8767E24@keescook
Fixes: ca90800a91 ("test_overflow: Add memory allocation overflow tests")
Signed-off-by: Kees Cook <keescook@chromium.org>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Suggested-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-16 19:23:22 -07:00
Kees Cook d36b6ad27c test_overflow: Add shift overflow tests
This adds overflow tests for the new check_shift_overflow() helper to
validate overflow, signedness glitches, storage glitches, etc.

Co-developed-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-08-08 09:47:26 -06:00
Dan Carpenter 8958fd411b test_overflow: fix an IS_ERR() vs NULL bug
root_device_register() returns error pointers, it never returns NULL.

Fixes: ca90800a91 ("test_overflow: Add memory allocation overflow tests")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 16:19:22 -07:00
Kees Cook ca90800a91 test_overflow: Add memory allocation overflow tests
Make sure that the memory allocators are behaving as expected in the face
of overflows of multiplied arguments or when using the array_size()-family
helpers.

Example output of new tests (with the expected __alloc_pages_slowpath
and vmalloc warnings about refusing giant allocations removed):

[   93.062076] test_overflow: kmalloc detected saturation
[   93.062988] test_overflow: kmalloc_node detected saturation
[   93.063818] test_overflow: kzalloc detected saturation
[   93.064539] test_overflow: kzalloc_node detected saturation
[   93.120386] test_overflow: kvmalloc detected saturation
[   93.143458] test_overflow: kvmalloc_node detected saturation
[   93.166861] test_overflow: kvzalloc detected saturation
[   93.189924] test_overflow: kvzalloc_node detected saturation
[   93.221671] test_overflow: vmalloc detected saturation
[   93.246326] test_overflow: vmalloc_node detected saturation
[   93.270260] test_overflow: vzalloc detected saturation
[   93.293824] test_overflow: vzalloc_node detected saturation
[   93.294597] test_overflow: devm_kmalloc detected saturation
[   93.295383] test_overflow: devm_kzalloc detected saturation
[   93.296217] test_overflow: all tests passed

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-05 12:16:51 -07:00
Kees Cook 8fee81aa45 test_overflow: Report test failures
This adjusts the overflow test to report failures, and prepares to
add allocation tests.

Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-05 12:16:51 -07:00
Rasmus Villemoes 6d3344324b test_overflow: macrofy some more, do more tests for free
Obviously a+b==b+a and a*b==b*a, but the implementation of the fallback
checks are not entirely symmetric in how they treat a and b. So we might
as well check the (b,a,r,of) tuple as well as the (a,b,r,of) one for +
and *. Rather than more copy-paste, factor out the common part to
check_one_op.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-05 12:16:51 -07:00
Rasmus Villemoes 455a35a6cd lib: add runtime test of check_*_overflow functions
This adds a small module for testing that the check_*_overflow
functions work as expected, whether implemented in C or using gcc
builtins.

Example output:

test_overflow: u8 : 18 tests
test_overflow: s8 : 19 tests
test_overflow: u16: 17 tests
test_overflow: s16: 17 tests
test_overflow: u32: 17 tests
test_overflow: s32: 17 tests
test_overflow: u64: 17 tests
test_overflow: s64: 21 tests

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
[kees: add output to commit log, drop u64 tests on 32-bit]
Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-05 12:16:51 -07:00