<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/kernel, branch v5.4.198</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.4.198</id>
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<updated>2022-06-14T16:11:56Z</updated>
<entry>
<title>tracing: Avoid adding tracer option before update_tracer_options</title>
<updated>2022-06-14T16:11:56Z</updated>
<author>
<name>Mark-PK Tsai</name>
<email>mark-pk.tsai@mediatek.com</email>
</author>
<published>2022-04-26T12:24:06Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=23b2163b887f1a997ea7378c8cb01d81ea8e94fb'/>
<id>urn:sha1:23b2163b887f1a997ea7378c8cb01d81ea8e94fb</id>
<content type='text'>
[ Upstream commit ef9188bcc6ca1d8a2ad83e826b548e6820721061 ]

To prepare for support asynchronous tracer_init_tracefs initcall,
avoid calling create_trace_option_files before __update_tracer_options.
Otherwise, create_trace_option_files will show warning because
some tracers in trace_types list are already in tr-&gt;topts.

For example, hwlat_tracer call register_tracer in late_initcall,
and global_trace.dir is already created in tracing_init_dentry,
hwlat_tracer will be put into tr-&gt;topts.
Then if the __update_tracer_options is executed after hwlat_tracer
registered, create_trace_option_files find that hwlat_tracer is
already in tr-&gt;topts.

Link: https://lkml.kernel.org/r/20220426122407.17042-2-mark-pk.tsai@mediatek.com

Link: https://lore.kernel.org/lkml/20220322133339.GA32582@xsang-OptiPlex-9020/
Reported-by: kernel test robot &lt;oliver.sang@intel.com&gt;
Signed-off-by: Mark-PK Tsai &lt;mark-pk.tsai@mediatek.com&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>tracing: Fix sleeping function called from invalid context on RT kernel</title>
<updated>2022-06-14T16:11:56Z</updated>
<author>
<name>Jun Miao</name>
<email>jun.miao@intel.com</email>
</author>
<published>2022-04-19T01:39:10Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=48c6ee7d6c614f09b2c8553a95eefef6ecf196e0'/>
<id>urn:sha1:48c6ee7d6c614f09b2c8553a95eefef6ecf196e0</id>
<content type='text'>
[ Upstream commit 12025abdc8539ed9d5014e2d647a3fd1bd3de5cd ]

When setting bootparams="trace_event=initcall:initcall_start tp_printk=1" in the
cmdline, the output_printk() was called, and the spin_lock_irqsave() was called in the
atomic and irq disable interrupt context suitation. On the PREEMPT_RT kernel,
these locks are replaced with sleepable rt-spinlock, so the stack calltrace will
be triggered.
Fix it by raw_spin_lock_irqsave when PREEMPT_RT and "trace_event=initcall:initcall_start
tp_printk=1" enabled.

 BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:46
 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1, name: swapper/0
 preempt_count: 2, expected: 0
 RCU nest depth: 0, expected: 0
 Preemption disabled at:
 [&lt;ffffffff8992303e&gt;] try_to_wake_up+0x7e/0xba0
 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.17.1-rt17+ #19 34c5812404187a875f32bee7977f7367f9679ea7
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
 Call Trace:
  &lt;TASK&gt;
  dump_stack_lvl+0x60/0x8c
  dump_stack+0x10/0x12
  __might_resched.cold+0x11d/0x155
  rt_spin_lock+0x40/0x70
  trace_event_buffer_commit+0x2fa/0x4c0
  ? map_vsyscall+0x93/0x93
  trace_event_raw_event_initcall_start+0xbe/0x110
  ? perf_trace_initcall_finish+0x210/0x210
  ? probe_sched_wakeup+0x34/0x40
  ? ttwu_do_wakeup+0xda/0x310
  ? trace_hardirqs_on+0x35/0x170
  ? map_vsyscall+0x93/0x93
  do_one_initcall+0x217/0x3c0
  ? trace_event_raw_event_initcall_level+0x170/0x170
  ? push_cpu_stop+0x400/0x400
  ? cblist_init_generic+0x241/0x290
  kernel_init_freeable+0x1ac/0x347
  ? _raw_spin_unlock_irq+0x65/0x80
  ? rest_init+0xf0/0xf0
  kernel_init+0x1e/0x150
  ret_from_fork+0x22/0x30
  &lt;/TASK&gt;

Link: https://lkml.kernel.org/r/20220419013910.894370-1-jun.miao@intel.com

Signed-off-by: Jun Miao &lt;jun.miao@intel.com&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>tracing: Fix potential double free in create_var_ref()</title>
<updated>2022-06-14T16:11:46Z</updated>
<author>
<name>Keita Suzuki</name>
<email>keitasuzuki.park@sslab.ics.keio.ac.jp</email>
</author>
<published>2022-04-25T06:37:38Z</published>
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<id>urn:sha1:c27f744ceefadc7bbeb14233b6abc150ced617d2</id>
<content type='text'>
commit 99696a2592bca641eb88cc9a80c90e591afebd0f upstream.

In create_var_ref(), init_var_ref() is called to initialize the fields
of variable ref_field, which is allocated in the previous function call
to create_hist_field(). Function init_var_ref() allocates the
corresponding fields such as ref_field-&gt;system, but frees these fields
when the function encounters an error. The caller later calls
destroy_hist_field() to conduct error handling, which frees the fields
and the variable itself. This results in double free of the fields which
are already freed in the previous function.

Fix this by storing NULL to the corresponding fields when they are freed
in init_var_ref().

Link: https://lkml.kernel.org/r/20220425063739.3859998-1-keitasuzuki.park@sslab.ics.keio.ac.jp

Fixes: 067fe038e70f ("tracing: Add variable reference handling to hist triggers")
CC: stable@vger.kernel.org
Reviewed-by: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Reviewed-by: Tom Zanussi &lt;zanussi@kernel.org&gt;
Signed-off-by: Keita Suzuki &lt;keitasuzuki.park@sslab.ics.keio.ac.jp&gt;
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>sched/fair: Fix cfs_rq_clock_pelt() for throttled cfs_rq</title>
<updated>2022-06-14T16:11:33Z</updated>
<author>
<name>Chengming Zhou</name>
<email>zhouchengming@bytedance.com</email>
</author>
<published>2022-04-08T11:53:08Z</published>
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<id>urn:sha1:735b57a960880dca055fcf739d7f434e380f1425</id>
<content type='text'>
[ Upstream commit 64eaf50731ac0a8c76ce2fedd50ef6652aabc5ff ]

Since commit 23127296889f ("sched/fair: Update scale invariance of PELT")
change to use rq_clock_pelt() instead of rq_clock_task(), we should also
use rq_clock_pelt() for throttled_clock_task_time and throttled_clock_task
accounting to get correct cfs_rq_clock_pelt() of throttled cfs_rq. And
rename throttled_clock_task(_time) to be clock_pelt rather than clock_task.

Fixes: 23127296889f ("sched/fair: Update scale invariance of PELT")
Signed-off-by: Chengming Zhou &lt;zhouchengming@bytedance.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Reviewed-by: Ben Segall &lt;bsegall@google.com&gt;
Reviewed-by: Vincent Guittot &lt;vincent.guittot@linaro.org&gt;
Link: https://lore.kernel.org/r/20220408115309.81603-1-zhouchengming@bytedance.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>bpf: Fix excessive memory allocation in stack_map_alloc()</title>
<updated>2022-06-14T16:11:32Z</updated>
<author>
<name>Yuntao Wang</name>
<email>ytcoode@gmail.com</email>
</author>
<published>2022-04-07T13:04:23Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=93c0f9d78dddd3e60062b83715e5fabd2692d6a0'/>
<id>urn:sha1:93c0f9d78dddd3e60062b83715e5fabd2692d6a0</id>
<content type='text'>
[ Upstream commit b45043192b3e481304062938a6561da2ceea46a6 ]

The 'n_buckets * (value_size + sizeof(struct stack_map_bucket))' part of the
allocated memory for 'smap' is never used after the memlock accounting was
removed, thus get rid of it.

[ Note, Daniel:

Commit b936ca643ade ("bpf: rework memlock-based memory accounting for maps")
moved `cost += n_buckets * (value_size + sizeof(struct stack_map_bucket))`
up and therefore before the bpf_map_area_alloc() allocation, sigh. In a later
step commit c85d69135a91 ("bpf: move memory size checks to bpf_map_charge_init()"),
and the overflow checks of `cost &gt;= U32_MAX - PAGE_SIZE` moved into
bpf_map_charge_init(). And then 370868107bf6 ("bpf: Eliminate rlimit-based
memory accounting for stackmap maps") finally removed the bpf_map_charge_init().
Anyway, the original code did the allocation same way as /after/ this fix. ]

Fixes: b936ca643ade ("bpf: rework memlock-based memory accounting for maps")
Signed-off-by: Yuntao Wang &lt;ytcoode@gmail.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Link: https://lore.kernel.org/bpf/20220407130423.798386-1-ytcoode@gmail.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>dma-debug: change allocation mode from GFP_NOWAIT to GFP_ATIOMIC</title>
<updated>2022-06-14T16:11:28Z</updated>
<author>
<name>Mikulas Patocka</name>
<email>mpatocka@redhat.com</email>
</author>
<published>2022-05-10T17:17:32Z</published>
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<id>urn:sha1:5a71f14a9b2e9054228dd105eceb58ca79beb025</id>
<content type='text'>
[ Upstream commit 84bc4f1dbbbb5f8aa68706a96711dccb28b518e5 ]

We observed the error "cacheline tracking ENOMEM, dma-debug disabled"
during a light system load (copying some files). The reason for this error
is that the dma_active_cacheline radix tree uses GFP_NOWAIT allocation -
so it can't access the emergency memory reserves and it fails as soon as
anybody reaches the watermark.

This patch changes GFP_NOWAIT to GFP_ATOMIC, so that it can access the
emergency memory reserves.

Signed-off-by: Mikulas Patocka &lt;mpatocka@redhat.com&gt;
Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>ptrace: Reimplement PTRACE_KILL by always sending SIGKILL</title>
<updated>2022-06-14T16:11:24Z</updated>
<author>
<name>Eric W. Biederman</name>
<email>ebiederm@xmission.com</email>
</author>
<published>2022-04-29T14:23:55Z</published>
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<id>urn:sha1:0ca5112047402e5395674ed1892fc87102090d73</id>
<content type='text'>
commit 6a2d90ba027adba528509ffa27097cffd3879257 upstream.

The current implementation of PTRACE_KILL is buggy and has been for
many years as it assumes it's target has stopped in ptrace_stop.  At a
quick skim it looks like this assumption has existed since ptrace
support was added in linux v1.0.

While PTRACE_KILL has been deprecated we can not remove it as
a quick search with google code search reveals many existing
programs calling it.

When the ptracee is not stopped at ptrace_stop some fields would be
set that are ignored except in ptrace_stop.  Making the userspace
visible behavior of PTRACE_KILL a noop in those case.

As the usual rules are not obeyed it is not clear what the
consequences are of calling PTRACE_KILL on a running process.
Presumably userspace does not do this as it achieves nothing.

Replace the implementation of PTRACE_KILL with a simple
send_sig_info(SIGKILL) followed by a return 0.  This changes the
observable user space behavior only in that PTRACE_KILL on a process
not stopped in ptrace_stop will also kill it.  As that has always
been the intent of the code this seems like a reasonable change.

Cc: stable@vger.kernel.org
Reported-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Suggested-by: Al Viro &lt;viro@zeniv.linux.org.uk&gt;
Tested-by: Kees Cook &lt;keescook@chromium.org&gt;
Reviewed-by: Oleg Nesterov &lt;oleg@redhat.com&gt;
Link: https://lkml.kernel.org/r/20220505182645.497868-7-ebiederm@xmission.com
Signed-off-by: "Eric W. Biederman" &lt;ebiederm@xmission.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>lockdown: also lock down previous kgdb use</title>
<updated>2022-06-06T06:33:48Z</updated>
<author>
<name>Daniel Thompson</name>
<email>daniel.thompson@linaro.org</email>
</author>
<published>2022-05-23T18:11:02Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=8bb828229da903bb5710d21065e0a29f9afd30e0'/>
<id>urn:sha1:8bb828229da903bb5710d21065e0a29f9afd30e0</id>
<content type='text'>
commit eadb2f47a3ced5c64b23b90fd2a3463f63726066 upstream.

KGDB and KDB allow read and write access to kernel memory, and thus
should be restricted during lockdown.  An attacker with access to a
serial port (for example, via a hypervisor console, which some cloud
vendors provide over the network) could trigger the debugger so it is
important that the debugger respect the lockdown mode when/if it is
triggered.

Fix this by integrating lockdown into kdb's existing permissions
mechanism.  Unfortunately kgdb does not have any permissions mechanism
(although it certainly could be added later) so, for now, kgdb is simply
and brutally disabled by immediately exiting the gdb stub without taking
any action.

For lockdowns established early in the boot (e.g. the normal case) then
this should be fine but on systems where kgdb has set breakpoints before
the lockdown is enacted than "bad things" will happen.

CVE: CVE-2022-21499
Co-developed-by: Stephen Brennan &lt;stephen.s.brennan@oracle.com&gt;
Signed-off-by: Stephen Brennan &lt;stephen.s.brennan@oracle.com&gt;
Reviewed-by: Douglas Anderson &lt;dianders@chromium.org&gt;
Signed-off-by: Daniel Thompson &lt;daniel.thompson@linaro.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>
</entry>
<entry>
<title>Reinstate some of "swiotlb: rework "fix info leak with DMA_FROM_DEVICE""</title>
<updated>2022-05-25T07:14:38Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-03-28T18:37:05Z</published>
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<id>urn:sha1:b2f140a9f980806f572d672e1780acea66b9a25c</id>
<content type='text'>
commit 901c7280ca0d5e2b4a8929fbe0bfb007ac2a6544 upstream.

Halil Pasic points out [1] that the full revert of that commit (revert
in bddac7c1e02b), and that a partial revert that only reverts the
problematic case, but still keeps some of the cleanups is probably
better.  ￼

And that partial revert [2] had already been verified by Oleksandr
Natalenko to also fix the issue, I had just missed that in the long
discussion.

So let's reinstate the cleanups from commit aa6f8dcbab47 ("swiotlb:
rework "fix info leak with DMA_FROM_DEVICE""), and effectively only
revert the part that caused problems.

Link: https://lore.kernel.org/all/20220328013731.017ae3e3.pasic@linux.ibm.com/ [1]
Link: https://lore.kernel.org/all/20220324055732.GB12078@lst.de/ [2]
Link: https://lore.kernel.org/all/4386660.LvFx2qVVIh@natalenko.name/ [3]
Suggested-by: Halil Pasic &lt;pasic@linux.ibm.com&gt;
Tested-by: Oleksandr Natalenko &lt;oleksandr@natalenko.name&gt;
Cc: Christoph Hellwig" &lt;hch@lst.de&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
[OP: backport to 5.4: adjusted context]
Signed-off-by: Ovidiu Panait &lt;ovidiu.panait@windriver.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>perf: Fix sys_perf_event_open() race against self</title>
<updated>2022-05-25T07:14:34Z</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2022-05-20T18:38:06Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=dd0ea88b0a0f913f82500e988ef38158a9ad9885'/>
<id>urn:sha1:dd0ea88b0a0f913f82500e988ef38158a9ad9885</id>
<content type='text'>
commit 3ac6487e584a1eb54071dbe1212e05b884136704 upstream.

Norbert reported that it's possible to race sys_perf_event_open() such
that the looser ends up in another context from the group leader,
triggering many WARNs.

The move_group case checks for races against itself, but the
!move_group case doesn't, seemingly relying on the previous
group_leader-&gt;ctx == ctx check. However, that check is racy due to not
holding any locks at that time.

Therefore, re-check the result after acquiring locks and bailing
if they no longer match.

Additionally, clarify the not_move_group case from the
move_group-vs-move_group race.

Fixes: f63a8daa5812 ("perf: Fix event-&gt;ctx locking")
Reported-by: Norbert Slusarek &lt;nslusarek@gmx.net&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.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>
</entry>
</feed>
