linux-stable.git/lib, branch v4.19.86 Linux kernel stable tree idr: Fix idr_get_next race with idr_remove 2019-11-24T07:19:11+00:00 Matthew Wilcox (Oracle) willy@infradead.org 2019-05-14T20:05:45+00:00 a16a3669273b4331fe5a0e4c7058c6e8df9d30b7 commit 5c089fd0c73411f2170ab795c9ffc16718c7d007 upstream. If the entry is deleted from the IDR between the call to radix_tree_iter_find() and rcu_dereference_raw(), idr_get_next() will return NULL, which will end the iteration prematurely. We should instead continue to the next entry in the IDR. This only happens if the iteration is protected by the RCU lock. Most IDR users use a spinlock or semaphore to exclude simultaneous modifications. It was noticed once the PID allocator was converted to use the IDR, as it uses the RCU lock, but there may be other users elsewhere in the kernel. We can't use the normal pattern of calling radix_tree_deref_retry() (which catches both a retry entry in a leaf node and a node entry in the root) as the IDR supports storing entries which are unaligned, which will trigger an infinite loop if they are encountered. Instead, we have to explicitly check whether the entry is a retry entry. Fixes: 0a835c4f090a ("Reimplement IDR and IDA using the radix tree") Reported-by: Brendan Gregg <bgregg@netflix.com> Tested-by: Brendan Gregg <bgregg@netflix.com> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 5c089fd0c73411f2170ab795c9ffc16718c7d007 upstream.

If the entry is deleted from the IDR between the call to
radix_tree_iter_find() and rcu_dereference_raw(), idr_get_next()
will return NULL, which will end the iteration prematurely.  We should
instead continue to the next entry in the IDR.  This only happens if the
iteration is protected by the RCU lock.  Most IDR users use a spinlock
or semaphore to exclude simultaneous modifications.  It was noticed once
the PID allocator was converted to use the IDR, as it uses the RCU lock,
but there may be other users elsewhere in the kernel.

We can't use the normal pattern of calling radix_tree_deref_retry()
(which catches both a retry entry in a leaf node and a node entry in
the root) as the IDR supports storing entries which are unaligned,
which will trigger an infinite loop if they are encountered.  Instead,
we have to explicitly check whether the entry is a retry entry.

Fixes: 0a835c4f090a ("Reimplement IDR and IDA using the radix tree")
Reported-by: Brendan Gregg <bgregg@netflix.com>
Tested-by: Brendan Gregg <bgregg@netflix.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
crypto: chacha20 - Fix chacha20_block() keystream alignment (again) 2019-11-20T17:47:11+00:00 Eric Biggers ebiggers@google.com 2018-09-12T03:05:10+00:00 ad28c2ba4318e9c882647c57edd5a435edf57907 [ Upstream commit a5e9f557098e54af44ade5d501379be18435bfbf ] In commit 9f480faec58c ("crypto: chacha20 - Fix keystream alignment for chacha20_block()"), I had missed that chacha20_block() can be called directly on the buffer passed to get_random_bytes(), which can have any alignment. So, while my commit didn't break anything, it didn't fully solve the alignment problems. Revert my solution and just update chacha20_block() to use put_unaligned_le32(), so the output buffer need not be aligned. This is simpler, and on many CPUs it's the same speed. But, I kept the 'tmp' buffers in extract_crng_user() and _get_random_bytes() 4-byte aligned, since that alignment is actually needed for _crng_backtrack_protect() too. Reported-by: Stephan Müller <smueller@chronox.de> Cc: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit a5e9f557098e54af44ade5d501379be18435bfbf ]

In commit 9f480faec58c ("crypto: chacha20 - Fix keystream alignment for
chacha20_block()"), I had missed that chacha20_block() can be called
directly on the buffer passed to get_random_bytes(), which can have any
alignment.  So, while my commit didn't break anything, it didn't fully
solve the alignment problems.

Revert my solution and just update chacha20_block() to use
put_unaligned_le32(), so the output buffer need not be aligned.
This is simpler, and on many CPUs it's the same speed.

But, I kept the 'tmp' buffers in extract_crng_user() and
_get_random_bytes() 4-byte aligned, since that alignment is actually
needed for _crng_backtrack_protect() too.

Reported-by: Stephan Müller <smueller@chronox.de>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
dump_stack: avoid the livelock of the dump_lock 2019-11-12T18:20:37+00:00 Kevin Hao haokexin@gmail.com 2019-11-06T05:16:57+00:00 8e358a02761106abcfaac5eb8c59e44ba923e8ca commit 5cbf2fff3bba8d3c6a4d47c1754de1cf57e2b01f upstream. In the current code, we use the atomic_cmpxchg() to serialize the output of the dump_stack(), but this implementation suffers the thundering herd problem. We have observed such kind of livelock on a Marvell cn96xx board(24 cpus) when heavily using the dump_stack() in a kprobe handler. Actually we can let the competitors to wait for the releasing of the lock before jumping to atomic_cmpxchg(). This will definitely mitigate the thundering herd problem. Thanks Linus for the suggestion. [akpm@linux-foundation.org: fix comment] Link: http://lkml.kernel.org/r/20191030031637.6025-1-haokexin@gmail.com Fixes: b58d977432c8 ("dump_stack: serialize the output from dump_stack()") Signed-off-by: Kevin Hao <haokexin@gmail.com> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 5cbf2fff3bba8d3c6a4d47c1754de1cf57e2b01f upstream.

In the current code, we use the atomic_cmpxchg() to serialize the output
of the dump_stack(), but this implementation suffers the thundering herd
problem.  We have observed such kind of livelock on a Marvell cn96xx
board(24 cpus) when heavily using the dump_stack() in a kprobe handler.
Actually we can let the competitors to wait for the releasing of the
lock before jumping to atomic_cmpxchg().  This will definitely mitigate
the thundering herd problem.  Thanks Linus for the suggestion.

[akpm@linux-foundation.org: fix comment]
Link: http://lkml.kernel.org/r/20191030031637.6025-1-haokexin@gmail.com
Fixes: b58d977432c8 ("dump_stack: serialize the output from dump_stack()")
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
lib: textsearch: fix escapes in example code 2019-10-29T08:19:35+00:00 Randy Dunlap rdunlap@infradead.org 2019-10-03T00:08:18+00:00 0cb5c7b06a0a5e3f3699673e49410a71cdbdf189 [ Upstream commit 2105b52e30debe7f19f3218598d8ae777dcc6776 ] This textsearch code example does not need the '\' escapes and they can be misleading to someone reading the example. Also, gcc and sparse warn that the "\%d" is an unknown escape sequence. Fixes: 5968a70d7af5 ("textsearch: fix kernel-doc warnings and add kernel-api section") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: netdev@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 2105b52e30debe7f19f3218598d8ae777dcc6776 ]

This textsearch code example does not need the '\' escapes and they can
be misleading to someone reading the example. Also, gcc and sparse warn
that the "\%d" is an unknown escape sequence.

Fixes: 5968a70d7af5 ("textsearch: fix kernel-doc warnings and add kernel-api section")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
kmemleak: increase DEBUG_KMEMLEAK_EARLY_LOG_SIZE default to 16K 2019-10-07T16:57:17+00:00 Nicolas Boichat drinkcat@chromium.org 2019-09-23T22:33:55+00:00 30ab799e758e9c00bb575e51d831c314f661abfb [ Upstream commit b751c52bb587ae66f773b15204ef7a147467f4c7 ] The current default value (400) is too low on many systems (e.g. some ARM64 platform takes up 1000+ entries). syzbot uses 16000 as default value, and has proved to be enough on beefy configurations, so let's pick that value. This consumes more RAM on boot (each entry is 160 bytes, so in total ~2.5MB of RAM), but the memory would later be freed (early_log is __initdata). Link: http://lkml.kernel.org/r/20190730154027.101525-1-drinkcat@chromium.org Signed-off-by: Nicolas Boichat <drinkcat@chromium.org> Suggested-by: Dmitry Vyukov <dvyukov@google.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Dmitry Vyukov <dvyukov@google.com> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Kees Cook <keescook@chromium.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Joe Lawrence <joe.lawrence@redhat.com> Cc: Uladzislau Rezki <urezki@gmail.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit b751c52bb587ae66f773b15204ef7a147467f4c7 ]

The current default value (400) is too low on many systems (e.g.  some
ARM64 platform takes up 1000+ entries).

syzbot uses 16000 as default value, and has proved to be enough on beefy
configurations, so let's pick that value.

This consumes more RAM on boot (each entry is 160 bytes, so in total
~2.5MB of RAM), but the memory would later be freed (early_log is
__initdata).

Link: http://lkml.kernel.org/r/20190730154027.101525-1-drinkcat@chromium.org
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Suggested-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Uladzislau Rezki <urezki@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
lib: logic_pio: Add logic_pio_unregister_range() 2019-09-06T08:22:19+00:00 John Garry john.garry@huawei.com 2019-07-30T13:29:54+00:00 c4616a9b3d3f8763532dfeded6a7e9e1f592bba7 commit b884e2de2afc68ce30f7093747378ef972dde253 upstream. Add a function to unregister a logical PIO range. Logical PIO space can still be leaked when unregistering certain LOGIC_PIO_CPU_MMIO regions, but this acceptable for now since there are no callers to unregister LOGIC_PIO_CPU_MMIO regions, and the logical PIO region allocation scheme would need significant work to improve this. Cc: stable@vger.kernel.org Signed-off-by: John Garry <john.garry@huawei.com> Signed-off-by: Wei Xu <xuwei5@hisilicon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit b884e2de2afc68ce30f7093747378ef972dde253 upstream.

Add a function to unregister a logical PIO range.

Logical PIO space can still be leaked when unregistering certain
LOGIC_PIO_CPU_MMIO regions, but this acceptable for now since there are no
callers to unregister LOGIC_PIO_CPU_MMIO regions, and the logical PIO
region allocation scheme would need significant work to improve this.

Cc: stable@vger.kernel.org
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
lib: logic_pio: Avoid possible overlap for unregistering regions 2019-09-06T08:22:19+00:00 John Garry john.garry@huawei.com 2019-07-30T13:29:53+00:00 7faef13e6f68d50aa50846cfc79ae499f82becf6 commit 0a27142bd1ee259e24a0be2b0133e5ca5df8da91 upstream. The code was originally written to not support unregistering logical PIO regions. To accommodate supporting unregistering logical PIO regions, subtly modify LOGIC_PIO_CPU_MMIO region registration code, such that the "end" of the registered regions is the "end" of the last region, and not the sum of the sizes of all the registered regions. Cc: stable@vger.kernel.org Signed-off-by: John Garry <john.garry@huawei.com> Signed-off-by: Wei Xu <xuwei5@hisilicon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 0a27142bd1ee259e24a0be2b0133e5ca5df8da91 upstream.

The code was originally written to not support unregistering logical PIO
regions.

To accommodate supporting unregistering logical PIO regions, subtly modify
LOGIC_PIO_CPU_MMIO region registration code, such that the "end" of the
registered regions is the "end" of the last region, and not the sum of
the sizes of all the registered regions.

Cc: stable@vger.kernel.org
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
lib: logic_pio: Fix RCU usage 2019-09-06T08:22:19+00:00 John Garry john.garry@huawei.com 2019-07-30T13:29:52+00:00 b865c2c6e3f2ab13196c736318f2112d22b7c9de commit 06709e81c668f5f56c65b806895b278517bd44e0 upstream. The traversing of io_range_list with list_for_each_entry_rcu() is not properly protected by rcu_read_lock() and rcu_read_unlock(), so add them. These functions mark the critical section scope where the list is protected for the reader, it cannot be "reclaimed". Any updater - in this case, the logical PIO registration functions - cannot update the list until the reader exits this critical section. In addition, the list traversing used in logic_pio_register_range() does not need to use the rcu variant. This is because we are already using io_range_mutex to guarantee mutual exclusion from mutating the list. Cc: stable@vger.kernel.org Fixes: 031e3601869c ("lib: Add generic PIO mapping method") Signed-off-by: John Garry <john.garry@huawei.com> Signed-off-by: Wei Xu <xuwei5@hisilicon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 06709e81c668f5f56c65b806895b278517bd44e0 upstream.

The traversing of io_range_list with list_for_each_entry_rcu()
is not properly protected by rcu_read_lock() and rcu_read_unlock(),
so add them.

These functions mark the critical section scope where the list is
protected for the reader, it cannot be  "reclaimed". Any updater - in
this case, the logical PIO registration functions - cannot update the
list until the reader exits this critical section.

In addition, the list traversing used in logic_pio_register_range()
does not need to use the rcu variant.

This is because we are already using io_range_mutex to guarantee mutual
exclusion from mutating the list.

Cc: stable@vger.kernel.org
Fixes: 031e3601869c ("lib: Add generic PIO mapping method")
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
test_firmware: fix a memory leak bug 2019-08-16T08:12:49+00:00 Wenwen Wang wenwen@cs.uga.edu 2019-07-14T06:11:35+00:00 0ba69e96cc625786bca775f4e9e8f9d06d512d1a [ Upstream commit d4fddac5a51c378c5d3e68658816c37132611e1f ] In test_firmware_init(), the buffer pointed to by the global pointer 'test_fw_config' is allocated through kzalloc(). Then, the buffer is initialized in __test_firmware_config_init(). In the case that the initialization fails, the following execution in test_firmware_init() needs to be terminated with an error code returned to indicate this failure. However, the allocated buffer is not freed on this execution path, leading to a memory leak bug. To fix the above issue, free the allocated buffer before returning from test_firmware_init(). Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu> Link: https://lore.kernel.org/r/1563084696-6865-1-git-send-email-wang6495@umn.edu Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit d4fddac5a51c378c5d3e68658816c37132611e1f ]

In test_firmware_init(), the buffer pointed to by the global pointer
'test_fw_config' is allocated through kzalloc(). Then, the buffer is
initialized in __test_firmware_config_init(). In the case that the
initialization fails, the following execution in test_firmware_init() needs
to be terminated with an error code returned to indicate this failure.
However, the allocated buffer is not freed on this execution path, leading
to a memory leak bug.

To fix the above issue, free the allocated buffer before returning from
test_firmware_init().

Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu>
Link: https://lore.kernel.org/r/1563084696-6865-1-git-send-email-wang6495@umn.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
lib/test_string.c: avoid masking memset16/32/64 failures 2019-08-06T17:06:51+00:00 Peter Rosin peda@axentia.se 2019-07-16T23:27:18+00:00 93b83005ea872555e7f1547d99b695654c75a020 [ Upstream commit 33d6e0ff68af74be0c846c8e042e84a9a1a0561e ] If a memsetXX implementation is completely broken and fails in the first iteration, when i, j, and k are all zero, the failure is masked as zero is returned. Failing in the first iteration is perhaps the most likely failure, so this makes the tests pretty much useless. Avoid the situation by always setting a random unused bit in the result on failure. Link: http://lkml.kernel.org/r/20190506124634.6807-3-peda@axentia.se Fixes: 03270c13c5ff ("lib/string.c: add testcases for memset16/32/64") Signed-off-by: Peter Rosin <peda@axentia.se> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 33d6e0ff68af74be0c846c8e042e84a9a1a0561e ]

If a memsetXX implementation is completely broken and fails in the first
iteration, when i, j, and k are all zero, the failure is masked as zero
is returned.  Failing in the first iteration is perhaps the most likely
failure, so this makes the tests pretty much useless.  Avoid the
situation by always setting a random unused bit in the result on
failure.

Link: http://lkml.kernel.org/r/20190506124634.6807-3-peda@axentia.se
Fixes: 03270c13c5ff ("lib/string.c: add testcases for memset16/32/64")
Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>