[ Upstream commit 334d7c4fb60cf21e0abac134d92fe49e9b04377e ]
If iov_offset is non-zero, then we need to consider iov_offset in length
calculation, otherwise we might pass smaller IOs such as 512 bytes, in
below scenario [1].
This issue is reproducible using lib-uring test/fixed-seg.c application
with fixed buffer on a 512 LBA formatted device.
[1]
At present we pass the alignment check, for 512 LBA formatted devices,
len_mask = 511 when IO is smaller, i->count = 512 has an offset,
i->io_offset = 3584 with bvec values, bvec->bv_offset = 256,
bvec->bv_len = 3840. In short, the first 256 bytes are in the current
page, next 256 bytes are in the another page. Ideally we expect to
fail the IO.
I can think of 2 userspace scenarios where we experience this.
a: From userspace, we observe a different behaviour when device LBA
size is 512 vs 4096 bytes. For 4096 LBA formatted device, I see the
same liburing test [2] failing, whereas 512 the test passes without
this. This is reproducible everytime.
[2] https://github.com/axboe/liburing/
b: Although I was not able to reproduce the below condition, but I
suspect below case should be possible from user space for devices
with 512 LBA formatted device. Lets say from userspace while
allocating a virtually single chunk of memory, if we get 2 physical
chunk of memory, and IO happens to be at the boundary of first
physical chunk with length crossing first chunk, then we allow IOs
to proceed and hence we might map wrong physical address length and
proceed with IO rather than failing.
: --- a/test/fixed-seg.c
: +++ b/test/fixed-seg.c
: @@ -64,7 +64,7 @@ static int test(struct io_uring *ring, int fd, int
: vec_off)
: return T_EXIT_FAIL;
: }
:
: - ret = read_it(ring, fd, 4096, vec_off);
: + ret = read_it(ring, fd, 4096, 7*512 + 256);
: if (ret) {
: fprintf(stderr, "4096 0 failed\n");
: return T_EXIT_FAIL;
Effectively this is a write crossing the page boundary.
Link: https://lkml.kernel.org/r/20250428095849.11709-1-nj.shetty@samsung.com
Fixes: 2263639f96f2 ("iov_iter: streamline iovec/bvec alignment iteration")
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Anuj Gupta <anuj20.g@samsung.com>
Signed-off-by: Nitesh Shetty <nj.shetty@samsung.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Keith Busch <kbusch@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d6a0e0bfecccdcecb08defe75a137c7262352102 ]
Depending on !COMPILE_TEST isn't sufficient to keep this feature out of
CI because we can't stop it from being included in randconfig builds.
This feature is still highly experimental, and is developed in lock-step
with Clang's Overflow Behavior Types[1]. Depend on BROKEN to keep it
from being enabled by anyone not expecting it.
Link: https://discourse.llvm.org/t/rfc-v2-clang-introduce-overflowbehaviortypes-for-wrapping-and-non-wrapping-arithmetic/86507 [1]
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202505281024.f42beaa7-lkp@intel.com
Fixes: 557f8c582a9b ("ubsan: Reintroduce signed overflow sanitizer")
Acked-by: Eric Biggers <ebiggers@kernel.org>
Link: https://lore.kernel.org/r/20250528182616.work.296-kees@kernel.org
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Marco Elver <elver@google.com>
Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0d6efa20e384a41a7f4afdcd8a0aec442c19d33e ]
usercopy of 64 bit values does not work on 32-bit SPARC:
# usercopy_test_valid: EXPECTATION FAILED at lib/tests/usercopy_kunit.c:209
Expected val_u64 == 0x5a5b5c5d6a6b6c6d, but
val_u64 == 1515936861 (0x5a5b5c5d)
0x5a5b5c5d6a6b6c6d == 6510899242581322861 (0x5a5b5c5d6a6b6c6d)
Disable the test.
Fixes: 4c5d7bc63775 ("usercopy: Add tests for all get_user() sizes")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Link: https://lore.kernel.org/r/20250416-kunit-sparc-usercopy-v1-1-a772054db3af@linutronix.de
Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 772e50a76ee664e75581624f512df4e45582605a ]
kunit_deactivate_static_stub() accepts real_fn_addr instead of
replacement_addr. In the case, it always passes NULL to
kunit_deactivate_static_stub().
Fix it.
Link: https://lore.kernel.org/r/20250520082050.2254875-1-tzungbi@kernel.org
Fixes: e047c5eaa763 ("kunit: Expose 'static stub' API to redirect functions")
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
When a module gets unloaded it checks whether any of its tags are still in
use and if so, we keep the memory containing module's allocation tags
alive until all tags are unused. However percpu counters referenced by
the tags are freed by free_module(). This will lead to UAF if the memory
allocated by a module is accessed after module was unloaded.
To fix this we allocate percpu counters for module allocation tags
dynamically and we keep it alive for tags which are still in use after
module unloading. This also removes the requirement of a larger
PERCPU_MODULE_RESERVE when memory allocation profiling is enabled because
percpu memory for counters does not need to be reserved anymore.
Link: https://lkml.kernel.org/r/20250517000739.5930-1-surenb@google.com
Fixes: 0db6f8d7820a ("alloc_tag: load module tags into separate contiguous memory")
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Reported-by: David Wang <00107082@163.com>
Closes: https://lore.kernel.org/all/20250516131246.6244-1-00107082@163.com/
Tested-by: David Wang <00107082@163.com>
Cc: Christoph Lameter (Ampere) <cl@gentwo.org>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Pull hardening fixes from Kees Cook: - lib/prime_numbers: KUnit test should not select PRIME_NUMBERS (Geert Uytterhoeven) - ubsan: Fix panic from test_ubsan_out_of_bounds (Mostafa Saleh) - ubsan: Remove 'default UBSAN' from UBSAN_INTEGER_WRAP (Nathan Chancellor) - string: Add load_unaligned_zeropad() code path to sized_strscpy() (Peter Collingbourne) - kasan: Add strscpy() test to trigger tag fault on arm64 (Vincenzo Frascino) - Disable GCC randstruct for COMPILE_TEST * tag 'hardening-v6.15-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: lib/prime_numbers: KUnit test should not select PRIME_NUMBERS ubsan: Fix panic from test_ubsan_out_of_bounds lib/Kconfig.ubsan: Remove 'default UBSAN' from UBSAN_INTEGER_WRAP hardening: Disable GCC randstruct for COMPILE_TEST kasan: Add strscpy() test to trigger tag fault on arm64 string: Add load_unaligned_zeropad() code path to sized_strscpy()
Pull misc hotfixes from Andrew Morton: "31 hotfixes. 9 are cc:stable and the remainder address post-6.15 issues or aren't considered necessary for -stable kernels. 22 patches are for MM, 9 are otherwise" * tag 'mm-hotfixes-stable-2025-04-16-19-59' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (31 commits) MAINTAINERS: update HUGETLB reviewers mm: fix apply_to_existing_page_range() selftests/mm: fix compiler -Wmaybe-uninitialized warning alloc_tag: handle incomplete bulk allocations in vm_module_tags_populate mailmap: add entry for Jean-Michel Hautbois mm: (un)track_pfn_copy() fix + doc improvements mm: fix filemap_get_folios_contig returning batches of identical folios mm/hugetlb: add a line break at the end of the format string selftests: mincore: fix tmpfs mincore test failure mm/hugetlb: fix set_max_huge_pages() when there are surplus pages mm/cma: report base address of single range correctly mm: page_alloc: speed up fallbacks in rmqueue_bulk() kunit: slub: add module description mm/kasan: add module decription ucs2_string: add module description zlib: add module description fpga: tests: add module descriptions samples/livepatch: add module descriptions ASN.1: add module description mm/vma: add give_up_on_oom option on modify/merge, use in uffd release ...
Enabling a (modular) test should not silently enable additional kernel
functionality, as that may increase the attack vector of a product.
Fix this by making PRIME_NUMBERS_KUNIT_TEST depend on PRIME_NUMBERS
instead of selecting it.
After this, one can safely enable CONFIG_KUNIT_ALL_TESTS=m to build
modules for all appropriate tests for ones system, without pulling in
extra unwanted functionality, while still allowing a tester to manually
enable PRIME_NUMBERS and this test suite on a system where PRIME_NUMBERS
is not enabled by default. Resurrect CONFIG_PRIME_NUMBERS=m in
tools/testing/selftests/lib/config for the latter use case.
Fixes: 313b38a6ecb46db4 ("lib/prime_numbers: convert self-test to KUnit")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Tamir Duberstein <tamird@gmail.com>
Link: https://lore.kernel.org/r/40f8a40eef4930d3ac9febd205bc171eb04e171c.1744641237.git.geert@linux-m68k.org
Signed-off-by: Kees Cook <kees@kernel.org>
Running lib_ubsan.ko on arm64 (without CONFIG_UBSAN_TRAP) panics the
kernel:
[ 31.616546] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: test_ubsan_out_of_bounds+0x158/0x158 [test_ubsan]
[ 31.646817] CPU: 3 UID: 0 PID: 179 Comm: insmod Not tainted 6.15.0-rc2 #1 PREEMPT
[ 31.648153] Hardware name: linux,dummy-virt (DT)
[ 31.648970] Call trace:
[ 31.649345] show_stack+0x18/0x24 (C)
[ 31.650960] dump_stack_lvl+0x40/0x84
[ 31.651559] dump_stack+0x18/0x24
[ 31.652264] panic+0x138/0x3b4
[ 31.652812] __ktime_get_real_seconds+0x0/0x10
[ 31.653540] test_ubsan_load_invalid_value+0x0/0xa8 [test_ubsan]
[ 31.654388] init_module+0x24/0xff4 [test_ubsan]
[ 31.655077] do_one_initcall+0xd4/0x280
[ 31.655680] do_init_module+0x58/0x2b4
That happens because the test corrupts other data in the stack:
400: d5384108 mrs x8, sp_el0
404: f9426d08 ldr x8, [x8, #1240]
408: f85f83a9 ldur x9, [x29, #-8]
40c: eb09011f cmp x8, x9
410: 54000301 b.ne 470 <test_ubsan_out_of_bounds+0x154> // b.any
As there is no guarantee the compiler will order the local variables
as declared in the module:
volatile char above[4] = { }; /* Protect surrounding memory. */
volatile int arr[4];
volatile char below[4] = { }; /* Protect surrounding memory. */
There is another problem where the out-of-bound index is 5 which is larger
than the extra surrounding memory for protection.
So, use a struct to enforce the ordering, and fix the index to be 4.
Also, remove some of the volatiles and rely on OPTIMIZER_HIDE_VAR()
Signed-off-by: Mostafa Saleh <smostafa@google.com>
Link: https://lore.kernel.org/r/20250415203354.4109415-1-smostafa@google.com
Signed-off-by: Kees Cook <kees@kernel.org>
CONFIG_UBSAN_INTEGER_WRAP is 'default UBSAN', which is problematic for a
couple of reasons.
The first is that this sanitizer is under active development on the
compiler side to come up with a solution that is maintainable on the
compiler side and usable on the kernel side. As a result of this, there
are many warnings when the sanitizer is enabled that have no clear path
to resolution yet but users may see them and report them in the meantime.
The second is that this option was renamed from
CONFIG_UBSAN_SIGNED_WRAP, meaning that if a configuration has
CONFIG_UBSAN=y but CONFIG_UBSAN_SIGNED_WRAP=n and it is upgraded via
olddefconfig (common in non-interactive scenarios such as CI),
CONFIG_UBSAN_INTEGER_WRAP will be silently enabled again.
Remove 'default UBSAN' from CONFIG_UBSAN_INTEGER_WRAP until it is ready
for regular usage and testing from a broader community than the folks
actively working on the feature.
Cc: stable@vger.kernel.org
Fixes: 557f8c582a9b ("ubsan: Reintroduce signed overflow sanitizer")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20250414-drop-default-ubsan-integer-wrap-v1-1-392522551d6b@kernel.org
Signed-off-by: Kees Cook <kees@kernel.org>