<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/kernel, branch v4.16.4</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>trace_uprobe: Use %lx to display offset</title>
<updated>2018-04-24T07:43:04+00:00</updated>
<author>
<name>Ravi Bangoria</name>
<email>ravi.bangoria@linux.vnet.ibm.com</email>
</author>
<published>2018-03-15T08:27:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0edc19e0c3850e1bc9facb13f2fd37a7e04fea02'/>
<id>0edc19e0c3850e1bc9facb13f2fd37a7e04fea02</id>
<content type='text'>
commit 18d45b11d96e6f9b3814960a1394083a3d6b7f74 upstream.

tu-&gt;offset is unsigned long, not a pointer, thus %lx should
be used to print it, not the %px.

Link: http://lkml.kernel.org/r/20180315082756.9050-1-ravi.bangoria@linux.vnet.ibm.com

Cc: stable@vger.kernel.org
Acked-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Fixes: 0e4d819d0893 ("trace_uprobe: Display correct offset in uprobe_events")
Suggested-by: Kees Cook &lt;keescook@chromium.org&gt;
Signed-off-by: Ravi Bangoria &lt;ravi.bangoria@linux.vnet.ibm.com&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.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 18d45b11d96e6f9b3814960a1394083a3d6b7f74 upstream.

tu-&gt;offset is unsigned long, not a pointer, thus %lx should
be used to print it, not the %px.

Link: http://lkml.kernel.org/r/20180315082756.9050-1-ravi.bangoria@linux.vnet.ibm.com

Cc: stable@vger.kernel.org
Acked-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Fixes: 0e4d819d0893 ("trace_uprobe: Display correct offset in uprobe_events")
Suggested-by: Kees Cook &lt;keescook@chromium.org&gt;
Signed-off-by: Ravi Bangoria &lt;ravi.bangoria@linux.vnet.ibm.com&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ring-buffer: Check if memory is available before allocation</title>
<updated>2018-04-24T07:43:02+00:00</updated>
<author>
<name>Steven Rostedt (VMware)</name>
<email>rostedt@goodmis.org</email>
</author>
<published>2018-04-02T14:33:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=15ecf44787134f7948c23ad5ad31b449c9e51fd7'/>
<id>15ecf44787134f7948c23ad5ad31b449c9e51fd7</id>
<content type='text'>
commit 2a872fa4e9c8adc79c830e4009e1cc0c013a9d8a upstream.

The ring buffer is made up of a link list of pages. When making the ring
buffer bigger, it will allocate all the pages it needs before adding to the
ring buffer, and if it fails, it frees them and returns an error. This makes
increasing the ring buffer size an all or nothing action. When this was
first created, the pages were allocated with "NORETRY". This was to not
cause any Out-Of-Memory (OOM) actions from allocating the ring buffer. But
NORETRY was too strict, as the ring buffer would fail to expand even when
there's memory available, but was taken up in the page cache.

Commit 848618857d253 ("tracing/ring_buffer: Try harder to allocate") changed
the allocating from NORETRY to RETRY_MAYFAIL. The RETRY_MAYFAIL would
allocate from the page cache, but if there was no memory available, it would
simple fail the allocation and not trigger an OOM.

This worked fine, but had one problem. As the ring buffer would allocate one
page at a time, it could take up all memory in the system before it failed
to allocate and free that memory. If the allocation is happening and the
ring buffer allocates all memory and then tries to take more than available,
its allocation will not trigger an OOM, but if there's any allocation that
happens someplace else, that could trigger an OOM, even though once the ring
buffer's allocation fails, it would free up all the previous memory it tried
to allocate, and allow other memory allocations to succeed.

Commit d02bd27bd33dd ("mm/page_alloc.c: calculate 'available' memory in a
separate function") separated out si_mem_availble() as a separate function
that could be used to see how much memory is available in the system. Using
this function to make sure that the ring buffer could be allocated before it
tries to allocate pages we can avoid allocating all memory in the system and
making it vulnerable to OOMs if other allocations are taking place.

Link: http://lkml.kernel.org/r/1522320104-6573-1-git-send-email-zhaoyang.huang@spreadtrum.com

CC: stable@vger.kernel.org
Cc: linux-mm@kvack.org
Fixes: 848618857d253 ("tracing/ring_buffer: Try harder to allocate")
Requires: d02bd27bd33dd ("mm/page_alloc.c: calculate 'available' memory in a separate function")
Reported-by: Zhaoyang Huang &lt;huangzhaoyang@gmail.com&gt;
Tested-by: Joel Fernandes &lt;joelaf@google.com&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.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 2a872fa4e9c8adc79c830e4009e1cc0c013a9d8a upstream.

The ring buffer is made up of a link list of pages. When making the ring
buffer bigger, it will allocate all the pages it needs before adding to the
ring buffer, and if it fails, it frees them and returns an error. This makes
increasing the ring buffer size an all or nothing action. When this was
first created, the pages were allocated with "NORETRY". This was to not
cause any Out-Of-Memory (OOM) actions from allocating the ring buffer. But
NORETRY was too strict, as the ring buffer would fail to expand even when
there's memory available, but was taken up in the page cache.

Commit 848618857d253 ("tracing/ring_buffer: Try harder to allocate") changed
the allocating from NORETRY to RETRY_MAYFAIL. The RETRY_MAYFAIL would
allocate from the page cache, but if there was no memory available, it would
simple fail the allocation and not trigger an OOM.

This worked fine, but had one problem. As the ring buffer would allocate one
page at a time, it could take up all memory in the system before it failed
to allocate and free that memory. If the allocation is happening and the
ring buffer allocates all memory and then tries to take more than available,
its allocation will not trigger an OOM, but if there's any allocation that
happens someplace else, that could trigger an OOM, even though once the ring
buffer's allocation fails, it would free up all the previous memory it tried
to allocate, and allow other memory allocations to succeed.

Commit d02bd27bd33dd ("mm/page_alloc.c: calculate 'available' memory in a
separate function") separated out si_mem_availble() as a separate function
that could be used to see how much memory is available in the system. Using
this function to make sure that the ring buffer could be allocated before it
tries to allocate pages we can avoid allocating all memory in the system and
making it vulnerable to OOMs if other allocations are taking place.

Link: http://lkml.kernel.org/r/1522320104-6573-1-git-send-email-zhaoyang.huang@spreadtrum.com

CC: stable@vger.kernel.org
Cc: linux-mm@kvack.org
Fixes: 848618857d253 ("tracing/ring_buffer: Try harder to allocate")
Requires: d02bd27bd33dd ("mm/page_alloc.c: calculate 'available' memory in a separate function")
Reported-by: Zhaoyang Huang &lt;huangzhaoyang@gmail.com&gt;
Tested-by: Joel Fernandes &lt;joelaf@google.com&gt;
Signed-off-by: Steven Rostedt (VMware) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>resource: fix integer overflow at reallocation</title>
<updated>2018-04-24T07:42:49+00:00</updated>
<author>
<name>Takashi Iwai</name>
<email>tiwai@suse.de</email>
</author>
<published>2018-04-13T22:35:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a401cbb69959821dfd14b0ea3bda3f00f8fea0c9'/>
<id>a401cbb69959821dfd14b0ea3bda3f00f8fea0c9</id>
<content type='text'>
commit 60bb83b81169820c691fbfa33a6a4aef32aa4b0b upstream.

We've got a bug report indicating a kernel panic at booting on an x86-32
system, and it turned out to be the invalid PCI resource assigned after
reallocation.  __find_resource() first aligns the resource start address
and resets the end address with start+size-1 accordingly, then checks
whether it's contained.  Here the end address may overflow the integer,
although resource_contains() still returns true because the function
validates only start and end address.  So this ends up with returning an
invalid resource (start &gt; end).

There was already an attempt to cover such a problem in the commit
47ea91b4052d ("Resource: fix wrong resource window calculation"), but
this case is an overseen one.

This patch adds the validity check of the newly calculated resource for
avoiding the integer overflow problem.

Bugzilla: http://bugzilla.opensuse.org/show_bug.cgi?id=1086739
Link: http://lkml.kernel.org/r/s5hpo37d5l8.wl-tiwai@suse.de
Fixes: 23c570a67448 ("resource: ability to resize an allocated resource")
Signed-off-by: Takashi Iwai &lt;tiwai@suse.de&gt;
Reported-by: Michael Henders &lt;hendersm@shaw.ca&gt;
Tested-by: Michael Henders &lt;hendersm@shaw.ca&gt;
Reviewed-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Ram Pai &lt;linuxram@us.ibm.com&gt;
Cc: Bjorn Helgaas &lt;bhelgaas@google.com&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 60bb83b81169820c691fbfa33a6a4aef32aa4b0b upstream.

We've got a bug report indicating a kernel panic at booting on an x86-32
system, and it turned out to be the invalid PCI resource assigned after
reallocation.  __find_resource() first aligns the resource start address
and resets the end address with start+size-1 accordingly, then checks
whether it's contained.  Here the end address may overflow the integer,
although resource_contains() still returns true because the function
validates only start and end address.  So this ends up with returning an
invalid resource (start &gt; end).

There was already an attempt to cover such a problem in the commit
47ea91b4052d ("Resource: fix wrong resource window calculation"), but
this case is an overseen one.

This patch adds the validity check of the newly calculated resource for
avoiding the integer overflow problem.

Bugzilla: http://bugzilla.opensuse.org/show_bug.cgi?id=1086739
Link: http://lkml.kernel.org/r/s5hpo37d5l8.wl-tiwai@suse.de
Fixes: 23c570a67448 ("resource: ability to resize an allocated resource")
Signed-off-by: Takashi Iwai &lt;tiwai@suse.de&gt;
Reported-by: Michael Henders &lt;hendersm@shaw.ca&gt;
Tested-by: Michael Henders &lt;hendersm@shaw.ca&gt;
Reviewed-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Ram Pai &lt;linuxram@us.ibm.com&gt;
Cc: Bjorn Helgaas &lt;bhelgaas@google.com&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>perf/core: Fix use-after-free in uprobe_perf_close()</title>
<updated>2018-04-19T06:54:07+00:00</updated>
<author>
<name>Prashant Bhole</name>
<email>bhole_prashant_q7@lab.ntt.co.jp</email>
</author>
<published>2018-04-09T10:03:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=122a80f16ee6d8bb3cd4e3b81a9bf32cda2ba61d'/>
<id>122a80f16ee6d8bb3cd4e3b81a9bf32cda2ba61d</id>
<content type='text'>
commit 621b6d2ea297d0fb6030452c5bcd221f12165fcf upstream.

A use-after-free bug was caught by KASAN while running usdt related
code (BCC project. bcc/tests/python/test_usdt2.py):

	==================================================================
	BUG: KASAN: use-after-free in uprobe_perf_close+0x222/0x3b0
	Read of size 4 at addr ffff880384f9b4a4 by task test_usdt2.py/870

	CPU: 4 PID: 870 Comm: test_usdt2.py Tainted: G        W         4.16.0-next-20180409 #215
	Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
	Call Trace:
	 dump_stack+0xc7/0x15b
	 ? show_regs_print_info+0x5/0x5
	 ? printk+0x9c/0xc3
	 ? kmsg_dump_rewind_nolock+0x6e/0x6e
	 ? uprobe_perf_close+0x222/0x3b0
	 print_address_description+0x83/0x3a0
	 ? uprobe_perf_close+0x222/0x3b0
	 kasan_report+0x1dd/0x460
	 ? uprobe_perf_close+0x222/0x3b0
	 uprobe_perf_close+0x222/0x3b0
	 ? probes_open+0x180/0x180
	 ? free_filters_list+0x290/0x290
	 trace_uprobe_register+0x1bb/0x500
	 ? perf_event_attach_bpf_prog+0x310/0x310
	 ? probe_event_disable+0x4e0/0x4e0
	 perf_uprobe_destroy+0x63/0xd0
	 _free_event+0x2bc/0xbd0
	 ? lockdep_rcu_suspicious+0x100/0x100
	 ? ring_buffer_attach+0x550/0x550
	 ? kvm_sched_clock_read+0x1a/0x30
	 ? perf_event_release_kernel+0x3e4/0xc00
	 ? __mutex_unlock_slowpath+0x12e/0x540
	 ? wait_for_completion+0x430/0x430
	 ? lock_downgrade+0x3c0/0x3c0
	 ? lock_release+0x980/0x980
	 ? do_raw_spin_trylock+0x118/0x150
	 ? do_raw_spin_unlock+0x121/0x210
	 ? do_raw_spin_trylock+0x150/0x150
	 perf_event_release_kernel+0x5d4/0xc00
	 ? put_event+0x30/0x30
	 ? fsnotify+0xd2d/0xea0
	 ? sched_clock_cpu+0x18/0x1a0
	 ? __fsnotify_update_child_dentry_flags.part.0+0x1b0/0x1b0
	 ? pvclock_clocksource_read+0x152/0x2b0
	 ? pvclock_read_flags+0x80/0x80
	 ? kvm_sched_clock_read+0x1a/0x30
	 ? sched_clock_cpu+0x18/0x1a0
	 ? pvclock_clocksource_read+0x152/0x2b0
	 ? locks_remove_file+0xec/0x470
	 ? pvclock_read_flags+0x80/0x80
	 ? fcntl_setlk+0x880/0x880
	 ? ima_file_free+0x8d/0x390
	 ? lockdep_rcu_suspicious+0x100/0x100
	 ? ima_file_check+0x110/0x110
	 ? fsnotify+0xea0/0xea0
	 ? kvm_sched_clock_read+0x1a/0x30
	 ? rcu_note_context_switch+0x600/0x600
	 perf_release+0x21/0x40
	 __fput+0x264/0x620
	 ? fput+0xf0/0xf0
	 ? do_raw_spin_unlock+0x121/0x210
	 ? do_raw_spin_trylock+0x150/0x150
	 ? SyS_fchdir+0x100/0x100
	 ? fsnotify+0xea0/0xea0
	 task_work_run+0x14b/0x1e0
	 ? task_work_cancel+0x1c0/0x1c0
	 ? copy_fd_bitmaps+0x150/0x150
	 ? vfs_read+0xe5/0x260
	 exit_to_usermode_loop+0x17b/0x1b0
	 ? trace_event_raw_event_sys_exit+0x1a0/0x1a0
	 do_syscall_64+0x3f6/0x490
	 ? syscall_return_slowpath+0x2c0/0x2c0
	 ? lockdep_sys_exit+0x1f/0xaa
	 ? syscall_return_slowpath+0x1a3/0x2c0
	 ? lockdep_sys_exit+0x1f/0xaa
	 ? prepare_exit_to_usermode+0x11c/0x1e0
	 ? enter_from_user_mode+0x30/0x30
	random: crng init done
	 ? __put_user_4+0x1c/0x30
	 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
	RIP: 0033:0x7f41d95f9340
	RSP: 002b:00007fffe71e4268 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
	RAX: 0000000000000000 RBX: 000000000000000d RCX: 00007f41d95f9340
	RDX: 0000000000000000 RSI: 0000000000002401 RDI: 000000000000000d
	RBP: 0000000000000000 R08: 00007f41ca8ff700 R09: 00007f41d996dd1f
	R10: 00007fffe71e41e0 R11: 0000000000000246 R12: 00007fffe71e4330
	R13: 0000000000000000 R14: fffffffffffffffc R15: 00007fffe71e4290

	Allocated by task 870:
	 kasan_kmalloc+0xa0/0xd0
	 kmem_cache_alloc_node+0x11a/0x430
	 copy_process.part.19+0x11a0/0x41c0
	 _do_fork+0x1be/0xa20
	 do_syscall_64+0x198/0x490
	 entry_SYSCALL_64_after_hwframe+0x3d/0xa2

	Freed by task 0:
	 __kasan_slab_free+0x12e/0x180
	 kmem_cache_free+0x102/0x4d0
	 free_task+0xfe/0x160
	 __put_task_struct+0x189/0x290
	 delayed_put_task_struct+0x119/0x250
	 rcu_process_callbacks+0xa6c/0x1b60
	 __do_softirq+0x238/0x7ae

	The buggy address belongs to the object at ffff880384f9b480
	 which belongs to the cache task_struct of size 12928

It occurs because task_struct is freed before perf_event which refers
to the task and task flags are checked while teardown of the event.
perf_event_alloc() assigns task_struct to hw.target of perf_event,
but there is no reference counting for it.

As a fix we get_task_struct() in perf_event_alloc() at above mentioned
assignment and put_task_struct() in _free_event().

Signed-off-by: Prashant Bhole &lt;bhole_prashant_q7@lab.ntt.co.jp&gt;
Reviewed-by: Oleg Nesterov &lt;oleg@redhat.com&gt;
Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Cc: &lt;stable@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Arnaldo Carvalho de Melo &lt;acme@kernel.org&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Fixes: 63b6da39bb38e8f1a1ef3180d32a39d6 ("perf: Fix perf_event_exit_task() race")
Link: http://lkml.kernel.org/r/20180409100346.6416-1-bhole_prashant_q7@lab.ntt.co.jp
Signed-off-by: Ingo Molnar &lt;mingo@kernel.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 621b6d2ea297d0fb6030452c5bcd221f12165fcf upstream.

A use-after-free bug was caught by KASAN while running usdt related
code (BCC project. bcc/tests/python/test_usdt2.py):

	==================================================================
	BUG: KASAN: use-after-free in uprobe_perf_close+0x222/0x3b0
	Read of size 4 at addr ffff880384f9b4a4 by task test_usdt2.py/870

	CPU: 4 PID: 870 Comm: test_usdt2.py Tainted: G        W         4.16.0-next-20180409 #215
	Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Ubuntu-1.8.2-1ubuntu1 04/01/2014
	Call Trace:
	 dump_stack+0xc7/0x15b
	 ? show_regs_print_info+0x5/0x5
	 ? printk+0x9c/0xc3
	 ? kmsg_dump_rewind_nolock+0x6e/0x6e
	 ? uprobe_perf_close+0x222/0x3b0
	 print_address_description+0x83/0x3a0
	 ? uprobe_perf_close+0x222/0x3b0
	 kasan_report+0x1dd/0x460
	 ? uprobe_perf_close+0x222/0x3b0
	 uprobe_perf_close+0x222/0x3b0
	 ? probes_open+0x180/0x180
	 ? free_filters_list+0x290/0x290
	 trace_uprobe_register+0x1bb/0x500
	 ? perf_event_attach_bpf_prog+0x310/0x310
	 ? probe_event_disable+0x4e0/0x4e0
	 perf_uprobe_destroy+0x63/0xd0
	 _free_event+0x2bc/0xbd0
	 ? lockdep_rcu_suspicious+0x100/0x100
	 ? ring_buffer_attach+0x550/0x550
	 ? kvm_sched_clock_read+0x1a/0x30
	 ? perf_event_release_kernel+0x3e4/0xc00
	 ? __mutex_unlock_slowpath+0x12e/0x540
	 ? wait_for_completion+0x430/0x430
	 ? lock_downgrade+0x3c0/0x3c0
	 ? lock_release+0x980/0x980
	 ? do_raw_spin_trylock+0x118/0x150
	 ? do_raw_spin_unlock+0x121/0x210
	 ? do_raw_spin_trylock+0x150/0x150
	 perf_event_release_kernel+0x5d4/0xc00
	 ? put_event+0x30/0x30
	 ? fsnotify+0xd2d/0xea0
	 ? sched_clock_cpu+0x18/0x1a0
	 ? __fsnotify_update_child_dentry_flags.part.0+0x1b0/0x1b0
	 ? pvclock_clocksource_read+0x152/0x2b0
	 ? pvclock_read_flags+0x80/0x80
	 ? kvm_sched_clock_read+0x1a/0x30
	 ? sched_clock_cpu+0x18/0x1a0
	 ? pvclock_clocksource_read+0x152/0x2b0
	 ? locks_remove_file+0xec/0x470
	 ? pvclock_read_flags+0x80/0x80
	 ? fcntl_setlk+0x880/0x880
	 ? ima_file_free+0x8d/0x390
	 ? lockdep_rcu_suspicious+0x100/0x100
	 ? ima_file_check+0x110/0x110
	 ? fsnotify+0xea0/0xea0
	 ? kvm_sched_clock_read+0x1a/0x30
	 ? rcu_note_context_switch+0x600/0x600
	 perf_release+0x21/0x40
	 __fput+0x264/0x620
	 ? fput+0xf0/0xf0
	 ? do_raw_spin_unlock+0x121/0x210
	 ? do_raw_spin_trylock+0x150/0x150
	 ? SyS_fchdir+0x100/0x100
	 ? fsnotify+0xea0/0xea0
	 task_work_run+0x14b/0x1e0
	 ? task_work_cancel+0x1c0/0x1c0
	 ? copy_fd_bitmaps+0x150/0x150
	 ? vfs_read+0xe5/0x260
	 exit_to_usermode_loop+0x17b/0x1b0
	 ? trace_event_raw_event_sys_exit+0x1a0/0x1a0
	 do_syscall_64+0x3f6/0x490
	 ? syscall_return_slowpath+0x2c0/0x2c0
	 ? lockdep_sys_exit+0x1f/0xaa
	 ? syscall_return_slowpath+0x1a3/0x2c0
	 ? lockdep_sys_exit+0x1f/0xaa
	 ? prepare_exit_to_usermode+0x11c/0x1e0
	 ? enter_from_user_mode+0x30/0x30
	random: crng init done
	 ? __put_user_4+0x1c/0x30
	 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
	RIP: 0033:0x7f41d95f9340
	RSP: 002b:00007fffe71e4268 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
	RAX: 0000000000000000 RBX: 000000000000000d RCX: 00007f41d95f9340
	RDX: 0000000000000000 RSI: 0000000000002401 RDI: 000000000000000d
	RBP: 0000000000000000 R08: 00007f41ca8ff700 R09: 00007f41d996dd1f
	R10: 00007fffe71e41e0 R11: 0000000000000246 R12: 00007fffe71e4330
	R13: 0000000000000000 R14: fffffffffffffffc R15: 00007fffe71e4290

	Allocated by task 870:
	 kasan_kmalloc+0xa0/0xd0
	 kmem_cache_alloc_node+0x11a/0x430
	 copy_process.part.19+0x11a0/0x41c0
	 _do_fork+0x1be/0xa20
	 do_syscall_64+0x198/0x490
	 entry_SYSCALL_64_after_hwframe+0x3d/0xa2

	Freed by task 0:
	 __kasan_slab_free+0x12e/0x180
	 kmem_cache_free+0x102/0x4d0
	 free_task+0xfe/0x160
	 __put_task_struct+0x189/0x290
	 delayed_put_task_struct+0x119/0x250
	 rcu_process_callbacks+0xa6c/0x1b60
	 __do_softirq+0x238/0x7ae

	The buggy address belongs to the object at ffff880384f9b480
	 which belongs to the cache task_struct of size 12928

It occurs because task_struct is freed before perf_event which refers
to the task and task flags are checked while teardown of the event.
perf_event_alloc() assigns task_struct to hw.target of perf_event,
but there is no reference counting for it.

As a fix we get_task_struct() in perf_event_alloc() at above mentioned
assignment and put_task_struct() in _free_event().

Signed-off-by: Prashant Bhole &lt;bhole_prashant_q7@lab.ntt.co.jp&gt;
Reviewed-by: Oleg Nesterov &lt;oleg@redhat.com&gt;
Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Cc: &lt;stable@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Arnaldo Carvalho de Melo &lt;acme@kernel.org&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Fixes: 63b6da39bb38e8f1a1ef3180d32a39d6 ("perf: Fix perf_event_exit_task() race")
Link: http://lkml.kernel.org/r/20180409100346.6416-1-bhole_prashant_q7@lab.ntt.co.jp
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>perf/hwbp: Simplify the perf-hwbp code, fix documentation</title>
<updated>2018-03-28T15:41:50+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-03-27T01:39:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f67b15037a7a50c57f72e69a6d59941ad90a0f0f'/>
<id>f67b15037a7a50c57f72e69a6d59941ad90a0f0f</id>
<content type='text'>
Annoyingly, modify_user_hw_breakpoint() unnecessarily complicates the
modification of a breakpoint - simplify it and remove the pointless
local variables.

Also update the stale Docbook while at it.

Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Acked-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Cc: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Cc: Vince Weaver &lt;vincent.weaver@maine.edu&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Annoyingly, modify_user_hw_breakpoint() unnecessarily complicates the
modification of a breakpoint - simplify it and remove the pointless
local variables.

Also update the stale Docbook while at it.

Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Acked-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Cc: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
Cc: Jiri Olsa &lt;jolsa@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Cc: Vince Weaver &lt;vincent.weaver@maine.edu&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2018-03-25T17:34:50+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-03-25T17:34:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9fd64e8ac2632929fb7f5d1245a15ae45ba21da6'/>
<id>9fd64e8ac2632929fb7f5d1245a15ae45ba21da6</id>
<content type='text'>
Pull timer fix from Ingo Molnar:
 "Make posix clock ID usage Spectre-safe"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  posix-timers: Protect posix clock array access against speculation
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull timer fix from Ingo Molnar:
 "Make posix clock ID usage Spectre-safe"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  posix-timers: Protect posix clock array access against speculation
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2018-03-25T17:33:30+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-03-25T17:33:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=bf45bae961d503b4cbf6c78d3ed71fe35e8f168d'/>
<id>bf45bae961d503b4cbf6c78d3ed71fe35e8f168d</id>
<content type='text'>
Pull scheduler fixes from Ingo Molnar:
 "Two sched debug output related fixes: a console output fix and
  formatting fixes"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/debug: Adjust newlines for better alignment
  sched/debug: Fix per-task line continuation for console output
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull scheduler fixes from Ingo Molnar:
 "Two sched debug output related fixes: a console output fix and
  formatting fixes"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/debug: Adjust newlines for better alignment
  sched/debug: Fix per-task line continuation for console output
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2018-03-25T17:27:32+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-03-25T17:27:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=eaf67993f5077c3eb0951f00704abe8d8113c0cf'/>
<id>eaf67993f5077c3eb0951f00704abe8d8113c0cf</id>
<content type='text'>
Pull perf fixes from Ingo Molnar:
 "Misc kernel side fixes.

  Generic:
   - cgroup events counting fix

  x86:
   - Intel PMU truncated-parameter fix

   - RDPMC fix

   - API naming fix/rename

   - uncore driver big-hardware PCI enumeration fix

   - uncore driver filter constraint fix"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/cgroup: Fix child event counting bug
  perf/x86/intel/uncore: Fix multi-domain PCI CHA enumeration bug on Skylake servers
  perf/x86/intel: Rename confusing 'freerunning PEBS' API and implementation to 'large PEBS'
  perf/x86/intel/uncore: Add missing filter constraint for SKX CHA event
  perf/x86/intel: Don't accidentally clear high bits in bdw_limit_period()
  perf/x86/intel: Disable userspace RDPMC usage for large PEBS
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull perf fixes from Ingo Molnar:
 "Misc kernel side fixes.

  Generic:
   - cgroup events counting fix

  x86:
   - Intel PMU truncated-parameter fix

   - RDPMC fix

   - API naming fix/rename

   - uncore driver big-hardware PCI enumeration fix

   - uncore driver filter constraint fix"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/cgroup: Fix child event counting bug
  perf/x86/intel/uncore: Fix multi-domain PCI CHA enumeration bug on Skylake servers
  perf/x86/intel: Rename confusing 'freerunning PEBS' API and implementation to 'large PEBS'
  perf/x86/intel/uncore: Add missing filter constraint for SKX CHA event
  perf/x86/intel: Don't accidentally clear high bits in bdw_limit_period()
  perf/x86/intel: Disable userspace RDPMC usage for large PEBS
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2018-03-25T17:18:31+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-03-25T17:18:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6bacf660776396d43e349817574715bbf229b8ab'/>
<id>6bacf660776396d43e349817574715bbf229b8ab</id>
<content type='text'>
Pull locking fixes from Ingo Molnar:
 "Two fixes: tighten up a jump-labels warning to not trigger on certain
  modules and fix confusing (and non-existent) mutex API documentation"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  jump_label: Disable jump labels in __exit code
  locking/mutex: Improve documentation
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull locking fixes from Ingo Molnar:
 "Two fixes: tighten up a jump-labels warning to not trigger on certain
  modules and fix confusing (and non-existent) mutex API documentation"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  jump_label: Disable jump labels in __exit code
  locking/mutex: Improve documentation
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'trace-v4.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace</title>
<updated>2018-03-23T22:34:18+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-03-23T22:34:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=99fec39e7725d091c94d1bb0242e40c8092994f6'/>
<id>99fec39e7725d091c94d1bb0242e40c8092994f6</id>
<content type='text'>
Pull kprobe fixes from Steven Rostedt:
 "The documentation for kprobe events says that symbol offets can take
  both a + and - sign to get to befor and after the symbol address.

  But in actuality, the code does not support the minus. This fixes that
  issue, and adds a few more selftests to kprobe events"

* tag 'trace-v4.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  selftests: ftrace: Add a testcase for probepoint
  selftests: ftrace: Add a testcase for string type with kprobe_event
  selftests: ftrace: Add probe event argument syntax testcase
  tracing: probeevent: Fix to support minus offset from symbol
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull kprobe fixes from Steven Rostedt:
 "The documentation for kprobe events says that symbol offets can take
  both a + and - sign to get to befor and after the symbol address.

  But in actuality, the code does not support the minus. This fixes that
  issue, and adds a few more selftests to kprobe events"

* tag 'trace-v4.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  selftests: ftrace: Add a testcase for probepoint
  selftests: ftrace: Add a testcase for string type with kprobe_event
  selftests: ftrace: Add probe event argument syntax testcase
  tracing: probeevent: Fix to support minus offset from symbol
</pre>
</div>
</content>
</entry>
</feed>
