linux-stable.git/lib, branch linux-5.13.y

lib/test_stackinit: Fix static initializer test

2021-09-18T11:42:22+00:00

commit f9398f15605a50110bf570aaa361163a85113dd1 upstream.

The static initializer test got accidentally converted to a dynamic
initializer. Fix this and retain the giant padding hole without using
an aligned struct member.

Fixes: 50ceaa95ea09 ("lib: Introduce test_stackinit module")
Cc: Ard Biesheuvel 
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook 
Link: https://lore.kernel.org/r/20210723221933.3431999-2-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman

bpf/tests: Do not PASS tests without actually testing the result

2021-09-18T11:42:03+00:00

[ Upstream commit 2b7e9f25e590726cca76700ebdb10e92a7a72ca1 ]

Each test case can have a set of sub-tests, where each sub-test can
run the cBPF/eBPF test snippet with its own data_size and expected
result. Before, the end of the sub-test array was indicated by both
data_size and result being zero. However, most or all of the internal
eBPF tests has a data_size of zero already. When such a test also had
an expected value of zero, the test was never run but reported as
PASS anyway.

Now the test runner always runs the first sub-test, regardless of the
data_size and result values. The sub-test array zero-termination only
applies for any additional sub-tests.

There are other ways fix it of course, but this solution at least
removes the surprise of eBPF tests with a zero result always succeeding.

Signed-off-by: Johan Almbladh 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20210721103822.3755111-1-johan.almbladh@anyfinetworks.com
Signed-off-by: Sasha Levin

bpf/tests: Fix copy-and-paste error in double word test

2021-09-18T11:42:03+00:00

[ Upstream commit ae7f47041d928b1a2f28717d095b4153c63cbf6a ]

This test now operates on DW as stated instead of W, which was
already covered by another test.

Signed-off-by: Johan Almbladh 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20210721104058.3755254-1-johan.almbladh@anyfinetworks.com
Signed-off-by: Sasha Levin

lib/mpi: use kcalloc in mpi_resize

2021-09-15T08:00:33+00:00

[ Upstream commit b6f756726e4dfe75be1883f6a0202dcecdc801ab ]

We should set the additional space to 0 in mpi_resize().
So use kcalloc() instead of kmalloc_array().

In lib/mpi/ec.c:
/****************
 * Resize the array of A to NLIMBS. the additional space is cleared
 * (set to 0) [done by m_realloc()]
 */
int mpi_resize(MPI a, unsigned nlimbs)

Like the comment of kernel's mpi_resize() said, the additional space
need to be set to 0, but when a->d is not NULL, it does not set.

The kernel's mpi lib is from libgcrypt, the mpi resize in libgcrypt
is _gcry_mpi_resize() which set the additional space to 0.

This bug may cause mpi api which use mpi_resize() get wrong result
under the condition of using the additional space without initiation.
If this condition is not met, the bug would not be triggered.
Currently in kernel, rsa, sm2 and dh use mpi lib, and they works well,
so the bug is not triggered in these cases.

add_points_edwards() use the additional space directly, so it will
get a wrong result.

Fixes: cdec9cb5167a ("crypto: GnuPG based MPI lib - source files (part 1)")
Signed-off-by: Hongbo Li 
Signed-off-by: Herbert Xu 
Signed-off-by: Sasha Levin

once: Fix panic when module unload

2021-09-03T08:22:46+00:00

[ Upstream commit 1027b96ec9d34f9abab69bc1a4dc5b1ad8ab1349 ]

DO_ONCE
DEFINE_STATIC_KEY_TRUE(___once_key);
__do_once_done
  once_disable_jump(once_key);
    INIT_WORK(&w->work, once_deferred);
    struct once_work *w;
    w->key = key;
    schedule_work(&w->work);                     module unload
                                                   //*the key is
destroy*
process_one_work
  once_deferred
    BUG_ON(!static_key_enabled(work->key));
       static_key_count((struct static_key *)x)    //*access key, crash*

When module uses DO_ONCE mechanism, it could crash due to the above
concurrency problem, we could reproduce it with link[1].

Fix it by add/put module refcount in the once work process.

[1] https://lore.kernel.org/netdev/eaa6c371-465e-57eb-6be9-f4b16b9d7cbf@huawei.com/

Cc: Hannes Frederic Sowa 
Cc: Daniel Borkmann 
Cc: David S. Miller 
Cc: Eric Dumazet 
Reported-by: Minmin chen 
Signed-off-by: Kefeng Wang 
Acked-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

lib: use PFN_PHYS() in devmem_is_allowed()

2021-08-18T07:06:46+00:00

commit 854f32648b8a5e424d682953b1a9f3b7c3322701 upstream.

The physical address may exceed 32 bits on 32-bit systems with more than
32 bits of physcial address.  Use PFN_PHYS() in devmem_is_allowed(), or
the physical address may overflow and be truncated.

We found this bug when mapping a high addresses through devmem tool,
when CONFIG_STRICT_DEVMEM is enabled on the ARM with ARM_LPAE and devmem
is used to map a high address that is not in the iomem address range, an
unexpected error indicating no permission is returned.

This bug was initially introduced from v2.6.37, and the function was
moved to lib in v5.11.

Link: https://lkml.kernel.org/r/20210731025057.78825-1-wangliang101@huawei.com
Fixes: 087aaffcdf9c ("ARM: implement CONFIG_STRICT_DEVMEM by disabling access to RAM via /dev/mem")
Fixes: 527701eda5f1 ("lib: Add a generic version of devmem_is_allowed()")
Signed-off-by: Liang Wang 
Reviewed-by: Luis Chamberlain 
Cc: Palmer Dabbelt 
Cc: Greg Kroah-Hartman 
Cc: Russell King 
Cc: Liang Wang 
Cc: Xiaoming Ni 
Cc: Kefeng Wang 
Cc: 	[2.6.37+]
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

lib/decompress_unlz4.c: correctly handle zero-padding around initrds.

2021-07-20T14:00:22+00:00

[ Upstream commit 2c484419efc09e7234c667aa72698cb79ba8d8ed ]

lz4 compatible decompressor is simple.  The format is underspecified and
relies on EOF notification to determine when to stop.  Initramfs buffer
format[1] explicitly states that it can have arbitrary number of zero
padding.  Thus when operating without a fill function, be extra careful to
ensure that sizes less than 4, or apperantly empty chunksizes are treated
as EOF.

To test this I have created two cpio initrds, first a normal one,
main.cpio.  And second one with just a single /test-file with content
"second" second.cpio.  Then i compressed both of them with gzip, and with
lz4 -l.  Then I created a padding of 4 bytes (dd if=/dev/zero of=pad4 bs=1
count=4).  To create four testcase initrds:

 1) main.cpio.gzip + extra.cpio.gzip = pad0.gzip
 2) main.cpio.lz4  + extra.cpio.lz4 = pad0.lz4
 3) main.cpio.gzip + pad4 + extra.cpio.gzip = pad4.gzip
 4) main.cpio.lz4  + pad4 + extra.cpio.lz4 = pad4.lz4

The pad4 test-cases replicate the initrd load by grub, as it pads and
aligns every initrd it loads.

All of the above boot, however /test-file was not accessible in the initrd
for the testcase #4, as decoding in lz4 decompressor failed.  Also an
error message printed which usually is harmless.

Whith a patched kernel, all of the above testcases now pass, and
/test-file is accessible.

This fixes lz4 initrd decompress warning on every boot with grub.  And
more importantly this fixes inability to load multiple lz4 compressed
initrds with grub.  This patch has been shipping in Ubuntu kernels since
January 2021.

[1] ./Documentation/driver-api/early-userspace/buffer-format.rst

BugLink: https://bugs.launchpad.net/bugs/1835660
Link: https://lore.kernel.org/lkml/20210114200256.196589-1-xnox@ubuntu.com/ # v0
Link: https://lkml.kernel.org/r/20210513104831.432975-1-dimitri.ledkov@canonical.com
Signed-off-by: Dimitri John Ledkov 
Cc: Kyungsik Lee 
Cc: Yinghai Lu 
Cc: Bongkyu Kim 
Cc: Kees Cook 
Cc: Sven Schmidt <4sschmid@informatik.uni-hamburg.de>
Cc: Rajat Asthana 
Cc: Nick Terrell 
Cc: Gao Xiang 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Sasha Levin

iov_iter_advance(): use consistent semantics for move past the end

2021-07-20T14:00:16+00:00

[ Upstream commit 3b3fc051cd2cba42bf736fa62780857d251a1236 ]

asking to advance by more than we have left in the iov_iter should
move to the very end; it should *not* leave negative i->count and
it should not spew into syslog, etc. - it's a legitimate operation.

Signed-off-by: Al Viro 
Signed-off-by: Sasha Levin

seq_buf: Fix overflow in seq_buf_putmem_hex()

2021-07-19T08:04:52+00:00

commit d3b16034a24a112bb83aeb669ac5b9b01f744bb7 upstream.

There's two variables being increased in that loop (i and j), and i
follows the raw data, and j follows what is being written into the buffer.
We should compare 'i' to MAX_MEMHEX_BYTES or compare 'j' to HEX_CHARS.
Otherwise, if 'j' goes bigger than HEX_CHARS, it will overflow the
destination buffer.

Link: https://lore.kernel.org/lkml/20210625122453.5e2fe304@oasis.local.home/
Link: https://lkml.kernel.org/r/20210626032156.47889-1-yun.zhou@windriver.com

Cc: stable@vger.kernel.org
Fixes: 5e3ca0ec76fce ("ftrace: introduce the "hex" output method")
Signed-off-by: Yun Zhou 
Signed-off-by: Steven Rostedt (VMware) 
Signed-off-by: Greg Kroah-Hartman

lib/math/rational.c: fix divide by zero

2021-07-14T15:07:48+00:00

[ Upstream commit 65a0d3c14685663ba111038a35db70f559e39336 ]

If the input is out of the range of the allowed values, either larger than
the largest value or closer to zero than the smallest non-zero allowed
value, then a division by zero would occur.

In the case of input too large, the division by zero will occur on the
first iteration.  The best result (largest allowed value) will be found by
always choosing the semi-convergent and excluding the denominator based
limit when finding it.

In the case of the input too small, the division by zero will occur on the
second iteration.  The numerator based semi-convergent should not be
calculated to avoid the division by zero.  But the semi-convergent vs
previous convergent test is still needed, which effectively chooses
between 0 (the previous convergent) vs the smallest allowed fraction (best
semi-convergent) as the result.

Link: https://lkml.kernel.org/r/20210525144250.214670-1-tpiepho@gmail.com
Fixes: 323dd2c3ed0 ("lib/math/rational.c: fix possible incorrect result from rational fractions helper")
Signed-off-by: Trent Piepho 
Reported-by: Yiyuan Guo 
Reviewed-by: Andy Shevchenko 
Cc: Oskar Schirmer 
Cc: Daniel Latypov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Sasha Levin