<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/lib, branch linux-5.0.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>kobject: Don't trigger kobject_uevent(KOBJ_REMOVE) twice.</title>
<updated>2019-05-31T13:45:14+00:00</updated>
<author>
<name>Tetsuo Handa</name>
<email>penguin-kernel@I-love.SAKURA.ne.jp</email>
</author>
<published>2019-03-17T05:02:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=29af8f36ea8b83eed0608d86fae1ff51d0b2728b'/>
<id>29af8f36ea8b83eed0608d86fae1ff51d0b2728b</id>
<content type='text'>
[ Upstream commit c03a0fd0b609e2f5c669c2b7f27c8e1928e9196e ]

syzbot is hitting use-after-free bug in uinput module [1]. This is because
kobject_uevent(KOBJ_REMOVE) is called again due to commit 0f4dafc0563c6c49
("Kobject: auto-cleanup on final unref") after memory allocation fault
injection made kobject_uevent(KOBJ_REMOVE) from device_del() from
input_unregister_device() fail, while uinput_destroy_device() is expecting
that kobject_uevent(KOBJ_REMOVE) is not called after device_del() from
input_unregister_device() completed.

That commit intended to catch cases where nobody even attempted to send
"remove" uevents. But there is no guarantee that an event will ultimately
be sent. We are at the point of no return as far as the rest of the kernel
is concerned; there are no repeats or do-overs.

Also, it is not clear whether some subsystem depends on that commit.
If no subsystem depends on that commit, it will be better to remove
the state_{add,remove}_uevent_sent logic. But we don't want to risk
a regression (in a patch which will be backported) by trying to remove
that logic. Therefore, as a first step, let's avoid the use-after-free bug
by making sure that kobject_uevent(KOBJ_REMOVE) won't be triggered twice.

[1] https://syzkaller.appspot.com/bug?id=8b17c134fe938bbddd75a45afaa9e68af43a362d

Reported-by: syzbot &lt;syzbot+f648cfb7e0b52bf7ae32@syzkaller.appspotmail.com&gt;
Analyzed-by: Dmitry Torokhov &lt;dmitry.torokhov@gmail.com&gt;
Fixes: 0f4dafc0563c6c49 ("Kobject: auto-cleanup on final unref")
Cc: Kay Sievers &lt;kay@vrfy.org&gt;
Signed-off-by: Tetsuo Handa &lt;penguin-kernel@I-love.SAKURA.ne.jp&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit c03a0fd0b609e2f5c669c2b7f27c8e1928e9196e ]

syzbot is hitting use-after-free bug in uinput module [1]. This is because
kobject_uevent(KOBJ_REMOVE) is called again due to commit 0f4dafc0563c6c49
("Kobject: auto-cleanup on final unref") after memory allocation fault
injection made kobject_uevent(KOBJ_REMOVE) from device_del() from
input_unregister_device() fail, while uinput_destroy_device() is expecting
that kobject_uevent(KOBJ_REMOVE) is not called after device_del() from
input_unregister_device() completed.

That commit intended to catch cases where nobody even attempted to send
"remove" uevents. But there is no guarantee that an event will ultimately
be sent. We are at the point of no return as far as the rest of the kernel
is concerned; there are no repeats or do-overs.

Also, it is not clear whether some subsystem depends on that commit.
If no subsystem depends on that commit, it will be better to remove
the state_{add,remove}_uevent_sent logic. But we don't want to risk
a regression (in a patch which will be backported) by trying to remove
that logic. Therefore, as a first step, let's avoid the use-after-free bug
by making sure that kobject_uevent(KOBJ_REMOVE) won't be triggered twice.

[1] https://syzkaller.appspot.com/bug?id=8b17c134fe938bbddd75a45afaa9e68af43a362d

Reported-by: syzbot &lt;syzbot+f648cfb7e0b52bf7ae32@syzkaller.appspotmail.com&gt;
Analyzed-by: Dmitry Torokhov &lt;dmitry.torokhov@gmail.com&gt;
Fixes: 0f4dafc0563c6c49 ("Kobject: auto-cleanup on final unref")
Cc: Kay Sievers &lt;kay@vrfy.org&gt;
Signed-off-by: Tetsuo Handa &lt;penguin-kernel@I-love.SAKURA.ne.jp&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mm/uaccess: Use 'unsigned long' to placate UBSAN warnings on older GCC versions</title>
<updated>2019-05-31T13:45:01+00:00</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2019-04-24T07:19:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=200aa576a8cdf81a724dfb1d73dc8998ccab1d6a'/>
<id>200aa576a8cdf81a724dfb1d73dc8998ccab1d6a</id>
<content type='text'>
[ Upstream commit 29da93fea3ea39ab9b12270cc6be1b70ef201c9e ]

Randy reported objtool triggered on his (GCC-7.4) build:

  lib/strncpy_from_user.o: warning: objtool: strncpy_from_user()+0x315: call to __ubsan_handle_add_overflow() with UACCESS enabled
  lib/strnlen_user.o: warning: objtool: strnlen_user()+0x337: call to __ubsan_handle_sub_overflow() with UACCESS enabled

This is due to UBSAN generating signed-overflow-UB warnings where it
should not. Prior to GCC-8 UBSAN ignored -fwrapv (which the kernel
uses through -fno-strict-overflow).

Make the functions use 'unsigned long' throughout.

Reported-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Acked-by: Randy Dunlap &lt;rdunlap@infradead.org&gt; # build-tested
Acked-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: luto@kernel.org
Link: http://lkml.kernel.org/r/20190424072208.754094071@infradead.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 29da93fea3ea39ab9b12270cc6be1b70ef201c9e ]

Randy reported objtool triggered on his (GCC-7.4) build:

  lib/strncpy_from_user.o: warning: objtool: strncpy_from_user()+0x315: call to __ubsan_handle_add_overflow() with UACCESS enabled
  lib/strnlen_user.o: warning: objtool: strnlen_user()+0x337: call to __ubsan_handle_sub_overflow() with UACCESS enabled

This is due to UBSAN generating signed-overflow-UB warnings where it
should not. Prior to GCC-8 UBSAN ignored -fwrapv (which the kernel
uses through -fno-strict-overflow).

Make the functions use 'unsigned long' throughout.

Reported-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Acked-by: Randy Dunlap &lt;rdunlap@infradead.org&gt; # build-tested
Acked-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: luto@kernel.org
Link: http://lkml.kernel.org/r/20190424072208.754094071@infradead.org
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>sbitmap: fix improper use of smp_mb__before_atomic()</title>
<updated>2019-05-31T13:44:45+00:00</updated>
<author>
<name>Andrea Parri</name>
<email>andrea.parri@amarulasolutions.com</email>
</author>
<published>2019-05-20T17:23:57+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=01b861eff8e5e78c41b6a7311a81d47a3204e9c1'/>
<id>01b861eff8e5e78c41b6a7311a81d47a3204e9c1</id>
<content type='text'>
commit a0934fd2b1208458e55fc4b48f55889809fce666 upstream.

This barrier only applies to the read-modify-write operations; in
particular, it does not apply to the atomic_set() primitive.

Replace the barrier with an smp_mb().

Fixes: 6c0ca7ae292ad ("sbitmap: fix wakeup hang after sbq resize")
Cc: stable@vger.kernel.org
Reported-by: "Paul E. McKenney" &lt;paulmck@linux.ibm.com&gt;
Reported-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Signed-off-by: Andrea Parri &lt;andrea.parri@amarulasolutions.com&gt;
Reviewed-by: Ming Lei &lt;ming.lei@redhat.com&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Omar Sandoval &lt;osandov@fb.com&gt;
Cc: Ming Lei &lt;ming.lei@redhat.com&gt;
Cc: linux-block@vger.kernel.org
Cc: "Paul E. McKenney" &lt;paulmck@linux.ibm.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit a0934fd2b1208458e55fc4b48f55889809fce666 upstream.

This barrier only applies to the read-modify-write operations; in
particular, it does not apply to the atomic_set() primitive.

Replace the barrier with an smp_mb().

Fixes: 6c0ca7ae292ad ("sbitmap: fix wakeup hang after sbq resize")
Cc: stable@vger.kernel.org
Reported-by: "Paul E. McKenney" &lt;paulmck@linux.ibm.com&gt;
Reported-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Signed-off-by: Andrea Parri &lt;andrea.parri@amarulasolutions.com&gt;
Reviewed-by: Ming Lei &lt;ming.lei@redhat.com&gt;
Cc: Jens Axboe &lt;axboe@kernel.dk&gt;
Cc: Omar Sandoval &lt;osandov@fb.com&gt;
Cc: Ming Lei &lt;ming.lei@redhat.com&gt;
Cc: linux-block@vger.kernel.org
Cc: "Paul E. McKenney" &lt;paulmck@linux.ibm.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>x86/mm/mem_encrypt: Disable all instrumentation for early SME setup</title>
<updated>2019-05-25T16:22:29+00:00</updated>
<author>
<name>Gary Hook</name>
<email>Gary.Hook@amd.com</email>
</author>
<published>2019-04-29T22:22:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=497ce5c7f5387d7cc0a17c414b247b1e7ef7e288'/>
<id>497ce5c7f5387d7cc0a17c414b247b1e7ef7e288</id>
<content type='text'>
[ Upstream commit b51ce3744f115850166f3d6c292b9c8cb849ad4f ]

Enablement of AMD's Secure Memory Encryption feature is determined very
early after start_kernel() is entered. Part of this procedure involves
scanning the command line for the parameter 'mem_encrypt'.

To determine intended state, the function sme_enable() uses library
functions cmdline_find_option() and strncmp(). Their use occurs early
enough such that it cannot be assumed that any instrumentation subsystem
is initialized.

For example, making calls to a KASAN-instrumented function before KASAN
is set up will result in the use of uninitialized memory and a boot
failure.

When AMD's SME support is enabled, conditionally disable instrumentation
of these dependent functions in lib/string.c and arch/x86/lib/cmdline.c.

 [ bp: Get rid of intermediary nostackp var and cleanup whitespace. ]

Fixes: aca20d546214 ("x86/mm: Add support to make use of Secure Memory Encryption")
Reported-by: Li RongQing &lt;lirongqing@baidu.com&gt;
Signed-off-by: Gary R Hook &lt;gary.hook@amd.com&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Cc: Boris Brezillon &lt;bbrezillon@kernel.org&gt;
Cc: Coly Li &lt;colyli@suse.de&gt;
Cc: "dave.hansen@linux.intel.com" &lt;dave.hansen@linux.intel.com&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Kent Overstreet &lt;kent.overstreet@gmail.com&gt;
Cc: "luto@kernel.org" &lt;luto@kernel.org&gt;
Cc: Masahiro Yamada &lt;yamada.masahiro@socionext.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: "mingo@redhat.com" &lt;mingo@redhat.com&gt;
Cc: "peterz@infradead.org" &lt;peterz@infradead.org&gt;
Cc: Sebastian Andrzej Siewior &lt;bigeasy@linutronix.de&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: x86-ml &lt;x86@kernel.org&gt;
Link: https://lkml.kernel.org/r/155657657552.7116.18363762932464011367.stgit@sosrh3.amd.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit b51ce3744f115850166f3d6c292b9c8cb849ad4f ]

Enablement of AMD's Secure Memory Encryption feature is determined very
early after start_kernel() is entered. Part of this procedure involves
scanning the command line for the parameter 'mem_encrypt'.

To determine intended state, the function sme_enable() uses library
functions cmdline_find_option() and strncmp(). Their use occurs early
enough such that it cannot be assumed that any instrumentation subsystem
is initialized.

For example, making calls to a KASAN-instrumented function before KASAN
is set up will result in the use of uninitialized memory and a boot
failure.

When AMD's SME support is enabled, conditionally disable instrumentation
of these dependent functions in lib/string.c and arch/x86/lib/cmdline.c.

 [ bp: Get rid of intermediary nostackp var and cleanup whitespace. ]

Fixes: aca20d546214 ("x86/mm: Add support to make use of Secure Memory Encryption")
Reported-by: Li RongQing &lt;lirongqing@baidu.com&gt;
Signed-off-by: Gary R Hook &lt;gary.hook@amd.com&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Cc: Boris Brezillon &lt;bbrezillon@kernel.org&gt;
Cc: Coly Li &lt;colyli@suse.de&gt;
Cc: "dave.hansen@linux.intel.com" &lt;dave.hansen@linux.intel.com&gt;
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Kent Overstreet &lt;kent.overstreet@gmail.com&gt;
Cc: "luto@kernel.org" &lt;luto@kernel.org&gt;
Cc: Masahiro Yamada &lt;yamada.masahiro@socionext.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: "mingo@redhat.com" &lt;mingo@redhat.com&gt;
Cc: "peterz@infradead.org" &lt;peterz@infradead.org&gt;
Cc: Sebastian Andrzej Siewior &lt;bigeasy@linutronix.de&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: x86-ml &lt;x86@kernel.org&gt;
Link: https://lkml.kernel.org/r/155657657552.7116.18363762932464011367.stgit@sosrh3.amd.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>iov_iter: optimize page_copy_sane()</title>
<updated>2019-05-22T05:38:58+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2019-02-26T18:42:39+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4999174b1a7772c2172804c2840cead989681a21'/>
<id>4999174b1a7772c2172804c2840cead989681a21</id>
<content type='text'>
commit 6daef95b8c914866a46247232a048447fff97279 upstream.

Avoid cache line miss dereferencing struct page if we can.

page_copy_sane() mostly deals with order-0 pages.

Extra cache line miss is visible on TCP recvmsg() calls dealing
with GRO packets (typically 45 page frags are attached to one skb).

Bringing the 45 struct pages into cpu cache while copying the data
is not free, since the freeing of the skb (and associated
page frags put_page()) can happen after cache lines have been evicted.

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 6daef95b8c914866a46247232a048447fff97279 upstream.

Avoid cache line miss dereferencing struct page if we can.

page_copy_sane() mostly deals with order-0 pages.

Extra cache line miss is visible on TCP recvmsg() calls dealing
with GRO packets (typically 45 page frags are attached to one skb).

Bringing the 45 struct pages into cpu cache while copying the data
is not free, since the freeing of the skb (and associated
page frags put_page()) can happen after cache lines have been evicted.

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>iov_iter: Fix build error without CONFIG_CRYPTO</title>
<updated>2019-05-10T16:36:08+00:00</updated>
<author>
<name>YueHaibing</name>
<email>yuehaibing@huawei.com</email>
</author>
<published>2019-04-04T02:31:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9680a806201d763b9f662b21f28570df7df56d88'/>
<id>9680a806201d763b9f662b21f28570df7df56d88</id>
<content type='text'>
[ Upstream commit 27fad74a5a77fe2e1f876db7bf27efcf2ec304b2 ]

If CONFIG_CRYPTO is not set or set to m,
gcc building warn this:

lib/iov_iter.o: In function `hash_and_copy_to_iter':
iov_iter.c:(.text+0x9129): undefined reference to `crypto_stats_get'
iov_iter.c:(.text+0x9152): undefined reference to `crypto_stats_ahash_update'

Reported-by: Hulk Robot &lt;hulkci@huawei.com&gt;
Fixes: d05f443554b3 ("iov_iter: introduce hash_and_copy_to_iter helper")
Suggested-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: YueHaibing &lt;yuehaibing@huawei.com&gt;
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 27fad74a5a77fe2e1f876db7bf27efcf2ec304b2 ]

If CONFIG_CRYPTO is not set or set to m,
gcc building warn this:

lib/iov_iter.o: In function `hash_and_copy_to_iter':
iov_iter.c:(.text+0x9129): undefined reference to `crypto_stats_get'
iov_iter.c:(.text+0x9152): undefined reference to `crypto_stats_ahash_update'

Reported-by: Hulk Robot &lt;hulkci@huawei.com&gt;
Fixes: d05f443554b3 ("iov_iter: introduce hash_and_copy_to_iter helper")
Suggested-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: YueHaibing &lt;yuehaibing@huawei.com&gt;
Signed-off-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>ubsan: Fix nasty -Wbuiltin-declaration-mismatch GCC-9 warnings</title>
<updated>2019-05-10T16:36:03+00:00</updated>
<author>
<name>Andrey Ryabinin</name>
<email>aryabinin@virtuozzo.com</email>
</author>
<published>2019-05-06T10:45:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9fe5b8e9d4c25d30c84703c409f2c62b074c9b2e'/>
<id>9fe5b8e9d4c25d30c84703c409f2c62b074c9b2e</id>
<content type='text'>
commit f0996bc2978e02d2ea898101462b960f6119b18f upstream.

Building lib/ubsan.c with gcc-9 results in a ton of nasty warnings like
this one:

    lib/ubsan.c warning: conflicting types for built-in function
         ‘__ubsan_handle_negate_overflow’; expected ‘void(void *, void *)’ [-Wbuiltin-declaration-mismatch]

The kernel's declarations of __ubsan_handle_*() often uses 'unsigned
long' types in parameters while GCC these parameters as 'void *' types,
hence the mismatch.

Fix this by using 'void *' to match GCC's declarations.

Reported-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Andrey Ryabinin &lt;aryabinin@virtuozzo.com&gt;
Fixes: c6d308534aef ("UBSAN: run-time undefined behavior sanity checker")
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit f0996bc2978e02d2ea898101462b960f6119b18f upstream.

Building lib/ubsan.c with gcc-9 results in a ton of nasty warnings like
this one:

    lib/ubsan.c warning: conflicting types for built-in function
         ‘__ubsan_handle_negate_overflow’; expected ‘void(void *, void *)’ [-Wbuiltin-declaration-mismatch]

The kernel's declarations of __ubsan_handle_*() often uses 'unsigned
long' types in parameters while GCC these parameters as 'void *' types,
hence the mismatch.

Fix this by using 'void *' to match GCC's declarations.

Reported-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Andrey Ryabinin &lt;aryabinin@virtuozzo.com&gt;
Fixes: c6d308534aef ("UBSAN: run-time undefined behavior sanity checker")
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>sbitmap: order READ/WRITE freed instance and setting clear bit</title>
<updated>2019-05-04T07:21:18+00:00</updated>
<author>
<name>Ming Lei</name>
<email>ming.lei@redhat.com</email>
</author>
<published>2019-03-22T01:13:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b2814ce32d478878ddcc44bc98e5d6ca282b1554'/>
<id>b2814ce32d478878ddcc44bc98e5d6ca282b1554</id>
<content type='text'>
[ Upstream commit e6d1fa584e0dd9bfebaf345e9feea588cf75ead2 ]

Inside sbitmap_queue_clear(), once the clear bit is set, it will be
visiable to allocation path immediately. Meantime READ/WRITE on old
associated instance(such as request in case of blk-mq) may be
out-of-order with the setting clear bit, so race with re-allocation
may be triggered.

Adds one memory barrier for ordering READ/WRITE of the freed associated
instance with setting clear bit for avoiding race with re-allocation.

The following kernel oops triggerd by block/006 on aarch64 may be fixed:

[  142.330954] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000330
[  142.338794] Mem abort info:
[  142.341554]   ESR = 0x96000005
[  142.344632]   Exception class = DABT (current EL), IL = 32 bits
[  142.350500]   SET = 0, FnV = 0
[  142.353544]   EA = 0, S1PTW = 0
[  142.356678] Data abort info:
[  142.359528]   ISV = 0, ISS = 0x00000005
[  142.363343]   CM = 0, WnR = 0
[  142.366305] user pgtable: 64k pages, 48-bit VAs, pgdp = 000000002a3c51c0
[  142.372983] [0000000000000330] pgd=0000000000000000, pud=0000000000000000
[  142.379777] Internal error: Oops: 96000005 [#1] SMP
[  142.384613] Modules linked in: null_blk ib_isert iscsi_target_mod ib_srpt target_core_mod ib_srp scsi_transport_srp vfat fat rpcrdma sunrpc rdma_ucm ib_iser rdma_cm iw_cm libiscsi ib_umad scsi_transport_iscsi ib_ipoib ib_cm mlx5_ib ib_uverbs ib_core sbsa_gwdt crct10dif_ce ghash_ce ipmi_ssif sha2_ce ipmi_devintf sha256_arm64 sg sha1_ce ipmi_msghandler ip_tables xfs libcrc32c mlx5_core sdhci_acpi mlxfw ahci_platform at803x sdhci libahci_platform qcom_emac mmc_core hdma hdma_mgmt i2c_dev [last unloaded: null_blk]
[  142.429753] CPU: 7 PID: 1983 Comm: fio Not tainted 5.0.0.cki #2
[  142.449458] pstate: 00400005 (nzcv daif +PAN -UAO)
[  142.454239] pc : __blk_mq_free_request+0x4c/0xa8
[  142.458830] lr : blk_mq_free_request+0xec/0x118
[  142.463344] sp : ffff00003360f6a0
[  142.466646] x29: ffff00003360f6a0 x28: ffff000010e70000
[  142.471941] x27: ffff801729a50048 x26: 0000000000010000
[  142.477232] x25: ffff00003360f954 x24: ffff7bdfff021440
[  142.482529] x23: 0000000000000000 x22: 00000000ffffffff
[  142.487830] x21: ffff801729810000 x20: 0000000000000000
[  142.493123] x19: ffff801729a50000 x18: 0000000000000000
[  142.498413] x17: 0000000000000000 x16: 0000000000000001
[  142.503709] x15: 00000000000000ff x14: ffff7fe000000000
[  142.509003] x13: ffff8017dcde09a0 x12: 0000000000000000
[  142.514308] x11: 0000000000000001 x10: 0000000000000008
[  142.519597] x9 : ffff8017dcde09a0 x8 : 0000000000002000
[  142.524889] x7 : ffff8017dcde0a00 x6 : 000000015388f9be
[  142.530187] x5 : 0000000000000001 x4 : 0000000000000000
[  142.535478] x3 : 0000000000000000 x2 : 0000000000000000
[  142.540777] x1 : 0000000000000001 x0 : ffff00001041b194
[  142.546071] Process fio (pid: 1983, stack limit = 0x000000006460a0ea)
[  142.552500] Call trace:
[  142.554926]  __blk_mq_free_request+0x4c/0xa8
[  142.559181]  blk_mq_free_request+0xec/0x118
[  142.563352]  blk_mq_end_request+0xfc/0x120
[  142.567444]  end_cmd+0x3c/0xa8 [null_blk]
[  142.571434]  null_complete_rq+0x20/0x30 [null_blk]
[  142.576194]  blk_mq_complete_request+0x108/0x148
[  142.580797]  null_handle_cmd+0x1d4/0x718 [null_blk]
[  142.585662]  null_queue_rq+0x60/0xa8 [null_blk]
[  142.590171]  blk_mq_try_issue_directly+0x148/0x280
[  142.594949]  blk_mq_try_issue_list_directly+0x9c/0x108
[  142.600064]  blk_mq_sched_insert_requests+0xb0/0xd0
[  142.604926]  blk_mq_flush_plug_list+0x16c/0x2a0
[  142.609441]  blk_flush_plug_list+0xec/0x118
[  142.613608]  blk_finish_plug+0x3c/0x4c
[  142.617348]  blkdev_direct_IO+0x3b4/0x428
[  142.621336]  generic_file_read_iter+0x84/0x180
[  142.625761]  blkdev_read_iter+0x50/0x78
[  142.629579]  aio_read.isra.6+0xf8/0x190
[  142.633409]  __io_submit_one.isra.8+0x148/0x738
[  142.637912]  io_submit_one.isra.9+0x88/0xb8
[  142.642078]  __arm64_sys_io_submit+0xe0/0x238
[  142.646428]  el0_svc_handler+0xa0/0x128
[  142.650238]  el0_svc+0x8/0xc
[  142.653104] Code: b9402a63 f9000a7f 3100047f 540000a0 (f9419a81)
[  142.659202] ---[ end trace 467586bc175eb09d ]---

Fixes: ea86ea2cdced20057da ("sbitmap: ammortize cost of clearing bits")
Reported-and-bisected_and_tested-by: Yi Zhang &lt;yi.zhang@redhat.com&gt;
Cc: Yi Zhang &lt;yi.zhang@redhat.com&gt;
Cc: "jianchao.wang" &lt;jianchao.w.wang@oracle.com&gt;
Reviewed-by: Omar Sandoval &lt;osandov@fb.com&gt;
Signed-off-by: Ming Lei &lt;ming.lei@redhat.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Sasha Levin (Microsoft) &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit e6d1fa584e0dd9bfebaf345e9feea588cf75ead2 ]

Inside sbitmap_queue_clear(), once the clear bit is set, it will be
visiable to allocation path immediately. Meantime READ/WRITE on old
associated instance(such as request in case of blk-mq) may be
out-of-order with the setting clear bit, so race with re-allocation
may be triggered.

Adds one memory barrier for ordering READ/WRITE of the freed associated
instance with setting clear bit for avoiding race with re-allocation.

The following kernel oops triggerd by block/006 on aarch64 may be fixed:

[  142.330954] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000330
[  142.338794] Mem abort info:
[  142.341554]   ESR = 0x96000005
[  142.344632]   Exception class = DABT (current EL), IL = 32 bits
[  142.350500]   SET = 0, FnV = 0
[  142.353544]   EA = 0, S1PTW = 0
[  142.356678] Data abort info:
[  142.359528]   ISV = 0, ISS = 0x00000005
[  142.363343]   CM = 0, WnR = 0
[  142.366305] user pgtable: 64k pages, 48-bit VAs, pgdp = 000000002a3c51c0
[  142.372983] [0000000000000330] pgd=0000000000000000, pud=0000000000000000
[  142.379777] Internal error: Oops: 96000005 [#1] SMP
[  142.384613] Modules linked in: null_blk ib_isert iscsi_target_mod ib_srpt target_core_mod ib_srp scsi_transport_srp vfat fat rpcrdma sunrpc rdma_ucm ib_iser rdma_cm iw_cm libiscsi ib_umad scsi_transport_iscsi ib_ipoib ib_cm mlx5_ib ib_uverbs ib_core sbsa_gwdt crct10dif_ce ghash_ce ipmi_ssif sha2_ce ipmi_devintf sha256_arm64 sg sha1_ce ipmi_msghandler ip_tables xfs libcrc32c mlx5_core sdhci_acpi mlxfw ahci_platform at803x sdhci libahci_platform qcom_emac mmc_core hdma hdma_mgmt i2c_dev [last unloaded: null_blk]
[  142.429753] CPU: 7 PID: 1983 Comm: fio Not tainted 5.0.0.cki #2
[  142.449458] pstate: 00400005 (nzcv daif +PAN -UAO)
[  142.454239] pc : __blk_mq_free_request+0x4c/0xa8
[  142.458830] lr : blk_mq_free_request+0xec/0x118
[  142.463344] sp : ffff00003360f6a0
[  142.466646] x29: ffff00003360f6a0 x28: ffff000010e70000
[  142.471941] x27: ffff801729a50048 x26: 0000000000010000
[  142.477232] x25: ffff00003360f954 x24: ffff7bdfff021440
[  142.482529] x23: 0000000000000000 x22: 00000000ffffffff
[  142.487830] x21: ffff801729810000 x20: 0000000000000000
[  142.493123] x19: ffff801729a50000 x18: 0000000000000000
[  142.498413] x17: 0000000000000000 x16: 0000000000000001
[  142.503709] x15: 00000000000000ff x14: ffff7fe000000000
[  142.509003] x13: ffff8017dcde09a0 x12: 0000000000000000
[  142.514308] x11: 0000000000000001 x10: 0000000000000008
[  142.519597] x9 : ffff8017dcde09a0 x8 : 0000000000002000
[  142.524889] x7 : ffff8017dcde0a00 x6 : 000000015388f9be
[  142.530187] x5 : 0000000000000001 x4 : 0000000000000000
[  142.535478] x3 : 0000000000000000 x2 : 0000000000000000
[  142.540777] x1 : 0000000000000001 x0 : ffff00001041b194
[  142.546071] Process fio (pid: 1983, stack limit = 0x000000006460a0ea)
[  142.552500] Call trace:
[  142.554926]  __blk_mq_free_request+0x4c/0xa8
[  142.559181]  blk_mq_free_request+0xec/0x118
[  142.563352]  blk_mq_end_request+0xfc/0x120
[  142.567444]  end_cmd+0x3c/0xa8 [null_blk]
[  142.571434]  null_complete_rq+0x20/0x30 [null_blk]
[  142.576194]  blk_mq_complete_request+0x108/0x148
[  142.580797]  null_handle_cmd+0x1d4/0x718 [null_blk]
[  142.585662]  null_queue_rq+0x60/0xa8 [null_blk]
[  142.590171]  blk_mq_try_issue_directly+0x148/0x280
[  142.594949]  blk_mq_try_issue_list_directly+0x9c/0x108
[  142.600064]  blk_mq_sched_insert_requests+0xb0/0xd0
[  142.604926]  blk_mq_flush_plug_list+0x16c/0x2a0
[  142.609441]  blk_flush_plug_list+0xec/0x118
[  142.613608]  blk_finish_plug+0x3c/0x4c
[  142.617348]  blkdev_direct_IO+0x3b4/0x428
[  142.621336]  generic_file_read_iter+0x84/0x180
[  142.625761]  blkdev_read_iter+0x50/0x78
[  142.629579]  aio_read.isra.6+0xf8/0x190
[  142.633409]  __io_submit_one.isra.8+0x148/0x738
[  142.637912]  io_submit_one.isra.9+0x88/0xb8
[  142.642078]  __arm64_sys_io_submit+0xe0/0x238
[  142.646428]  el0_svc_handler+0xa0/0x128
[  142.650238]  el0_svc+0x8/0xc
[  142.653104] Code: b9402a63 f9000a7f 3100047f 540000a0 (f9419a81)
[  142.659202] ---[ end trace 467586bc175eb09d ]---

Fixes: ea86ea2cdced20057da ("sbitmap: ammortize cost of clearing bits")
Reported-and-bisected_and_tested-by: Yi Zhang &lt;yi.zhang@redhat.com&gt;
Cc: Yi Zhang &lt;yi.zhang@redhat.com&gt;
Cc: "jianchao.wang" &lt;jianchao.w.wang@oracle.com&gt;
Reviewed-by: Omar Sandoval &lt;osandov@fb.com&gt;
Signed-off-by: Ming Lei &lt;ming.lei@redhat.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Sasha Levin (Microsoft) &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>lib/Kconfig.debug: fix build error without CONFIG_BLOCK</title>
<updated>2019-05-02T08:02:44+00:00</updated>
<author>
<name>YueHaibing</name>
<email>yuehaibing@huawei.com</email>
</author>
<published>2019-04-26T05:23:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=928962e99694c00808834ea608c2db17ec66aab4'/>
<id>928962e99694c00808834ea608c2db17ec66aab4</id>
<content type='text'>
commit ae3d6a323347940f0548bbb4b17f0bb2e9164169 upstream.

If CONFIG_TEST_KMOD is set to M, while CONFIG_BLOCK is not set, XFS and
BTRFS can not be compiled successly.

Link: http://lkml.kernel.org/r/20190410075434.35220-1-yuehaibing@huawei.com
Fixes: d9c6a72d6fa2 ("kmod: add test driver to stress test the module loader")
Signed-off-by: YueHaibing &lt;yuehaibing@huawei.com&gt;
Reported-by: Hulk Robot &lt;hulkci@huawei.com&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Masahiro Yamada &lt;yamada.masahiro@socionext.com&gt;
Cc: Petr Mladek &lt;pmladek@suse.com&gt;
Cc: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Joe Lawrence &lt;joe.lawrence@redhat.com&gt;
Cc: Robin Murphy &lt;robin.murphy@arm.com&gt;
Cc: Luis Chamberlain &lt;mcgrof@kernel.org&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit ae3d6a323347940f0548bbb4b17f0bb2e9164169 upstream.

If CONFIG_TEST_KMOD is set to M, while CONFIG_BLOCK is not set, XFS and
BTRFS can not be compiled successly.

Link: http://lkml.kernel.org/r/20190410075434.35220-1-yuehaibing@huawei.com
Fixes: d9c6a72d6fa2 ("kmod: add test driver to stress test the module loader")
Signed-off-by: YueHaibing &lt;yuehaibing@huawei.com&gt;
Reported-by: Hulk Robot &lt;hulkci@huawei.com&gt;
Reviewed-by: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Masahiro Yamada &lt;yamada.masahiro@socionext.com&gt;
Cc: Petr Mladek &lt;pmladek@suse.com&gt;
Cc: Andy Shevchenko &lt;andriy.shevchenko@linux.intel.com&gt;
Cc: Matthew Wilcox &lt;willy@infradead.org&gt;
Cc: Joe Lawrence &lt;joe.lawrence@redhat.com&gt;
Cc: Robin Murphy &lt;robin.murphy@arm.com&gt;
Cc: Luis Chamberlain &lt;mcgrof@kernel.org&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>lib/div64.c: off by one in shift</title>
<updated>2019-04-20T07:17:04+00:00</updated>
<author>
<name>Stanislaw Gruszka</name>
<email>sgruszka@redhat.com</email>
</author>
<published>2019-03-08T00:28:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=78154e3198885b037aa30bbf9539747c2692656a'/>
<id>78154e3198885b037aa30bbf9539747c2692656a</id>
<content type='text'>
[ Upstream commit cdc94a37493135e355dfc0b0e086d84e3eadb50d ]

fls counts bits starting from 1 to 32 (returns 0 for zero argument).  If
we add 1 we shift right one bit more and loose precision from divisor,
what cause function incorect results with some numbers.

Corrected code was tested in user-space, see bugzilla:
   https://bugzilla.kernel.org/show_bug.cgi?id=202391

Link: http://lkml.kernel.org/r/1548686944-11891-1-git-send-email-sgruszka@redhat.com
Fixes: 658716d19f8f ("div64_u64(): improve precision on 32bit platforms")
Signed-off-by: Stanislaw Gruszka &lt;sgruszka@redhat.com&gt;
Reported-by: Siarhei Volkau &lt;lis8215@gmail.com&gt;
Tested-by: Siarhei Volkau &lt;lis8215@gmail.com&gt;
Acked-by: Oleg Nesterov &lt;oleg@redhat.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit cdc94a37493135e355dfc0b0e086d84e3eadb50d ]

fls counts bits starting from 1 to 32 (returns 0 for zero argument).  If
we add 1 we shift right one bit more and loose precision from divisor,
what cause function incorect results with some numbers.

Corrected code was tested in user-space, see bugzilla:
   https://bugzilla.kernel.org/show_bug.cgi?id=202391

Link: http://lkml.kernel.org/r/1548686944-11891-1-git-send-email-sgruszka@redhat.com
Fixes: 658716d19f8f ("div64_u64(): improve precision on 32bit platforms")
Signed-off-by: Stanislaw Gruszka &lt;sgruszka@redhat.com&gt;
Reported-by: Siarhei Volkau &lt;lis8215@gmail.com&gt;
Tested-by: Siarhei Volkau &lt;lis8215@gmail.com&gt;
Acked-by: Oleg Nesterov &lt;oleg@redhat.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
