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<title>user/sven/linux.git/kernel, branch v5.15.86</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.15.86</id>
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<updated>2022-12-31T12:14:47Z</updated>
<entry>
<title>gcov: add support for checksum field</title>
<updated>2022-12-31T12:14:47Z</updated>
<author>
<name>Rickard x Andersson</name>
<email>rickaran@axis.com</email>
</author>
<published>2022-12-20T10:23:18Z</published>
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<id>urn:sha1:ca8bcb348aa826bb5a3cb694636a6ac78a7aaee3</id>
<content type='text'>
commit e96b95c2b7a63a454b6498e2df67aac14d046d13 upstream.

In GCC version 12.1 a checksum field was added.

This patch fixes a kernel crash occurring during boot when using
gcov-kernel with GCC version 12.2.  The crash occurred on a system running
on i.MX6SX.

Link: https://lkml.kernel.org/r/20221220102318.3418501-1-rickaran@axis.com
Fixes: 977ef30a7d88 ("gcov: support GCC 12.1 and newer compilers")
Signed-off-by: Rickard x Andersson &lt;rickaran@axis.com&gt;
Reviewed-by: Peter Oberparleiter &lt;oberpar@linux.ibm.com&gt;
Tested-by: Peter Oberparleiter &lt;oberpar@linux.ibm.com&gt;
Reviewed-by: Martin Liska &lt;mliska@suse.cz&gt;
Cc: &lt;stable@vger.kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>bpf: Prevent decl_tag from being referenced in func_proto arg</title>
<updated>2022-12-31T12:14:42Z</updated>
<author>
<name>Stanislav Fomichev</name>
<email>sdf@google.com</email>
</author>
<published>2022-11-23T03:54:22Z</published>
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<id>urn:sha1:b327c68ace71ba9cb3105ae6a5955a229e9bdca3</id>
<content type='text'>
[ Upstream commit f17472d4599697d701aa239b4c475a506bccfd19 ]

Syzkaller managed to hit another decl_tag issue:

  btf_func_proto_check kernel/bpf/btf.c:4506 [inline]
  btf_check_all_types kernel/bpf/btf.c:4734 [inline]
  btf_parse_type_sec+0x1175/0x1980 kernel/bpf/btf.c:4763
  btf_parse kernel/bpf/btf.c:5042 [inline]
  btf_new_fd+0x65a/0xb00 kernel/bpf/btf.c:6709
  bpf_btf_load+0x6f/0x90 kernel/bpf/syscall.c:4342
  __sys_bpf+0x50a/0x6c0 kernel/bpf/syscall.c:5034
  __do_sys_bpf kernel/bpf/syscall.c:5093 [inline]
  __se_sys_bpf kernel/bpf/syscall.c:5091 [inline]
  __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5091
  do_syscall_64+0x54/0x70 arch/x86/entry/common.c:48

This seems similar to commit ea68376c8bed ("bpf: prevent decl_tag from being
referenced in func_proto") but for the argument.

Reported-by: syzbot+8dd0551dda6020944c5d@syzkaller.appspotmail.com
Signed-off-by: Stanislav Fomichev &lt;sdf@google.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Acked-by: Yonghong Song &lt;yhs@fb.com&gt;
Link: https://lore.kernel.org/bpf/20221123035422.872531-2-sdf@google.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>acct: fix potential integer overflow in encode_comp_t()</title>
<updated>2022-12-31T12:14:40Z</updated>
<author>
<name>Zheng Yejian</name>
<email>zhengyejian1@huawei.com</email>
</author>
<published>2021-05-15T14:06:31Z</published>
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<id>urn:sha1:ebe16676e1dcaa4556ec4d36ca40c82e99e88cfa</id>
<content type='text'>
[ Upstream commit c5f31c655bcc01b6da53b836ac951c1556245305 ]

The integer overflow is descripted with following codes:
  &gt; 317 static comp_t encode_comp_t(u64 value)
  &gt; 318 {
  &gt; 319         int exp, rnd;
    ......
  &gt; 341         exp &lt;&lt;= MANTSIZE;
  &gt; 342         exp += value;
  &gt; 343         return exp;
  &gt; 344 }

Currently comp_t is defined as type of '__u16', but the variable 'exp' is
type of 'int', so overflow would happen when variable 'exp' in line 343 is
greater than 65535.

Link: https://lkml.kernel.org/r/20210515140631.369106-3-zhengyejian1@huawei.com
Signed-off-by: Zheng Yejian &lt;zhengyejian1@huawei.com&gt;
Cc: Hanjun Guo &lt;guohanjun@huawei.com&gt;
Cc: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Cc: Vlastimil Babka &lt;vbabka@suse.cz&gt;
Cc: Zhang Jinhao &lt;zhangjinhao2@huawei.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>rcu: Fix __this_cpu_read() lockdep warning in rcu_force_quiescent_state()</title>
<updated>2022-12-31T12:14:39Z</updated>
<author>
<name>Zqiang</name>
<email>qiang1.zhang@intel.com</email>
</author>
<published>2022-10-13T04:41:48Z</published>
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<id>urn:sha1:98a5b1265a36e9d843a51ddd6c9fa02da50d2c57</id>
<content type='text'>
[ Upstream commit ceb1c8c9b8aa9199da46a0f29d2d5f08d9b44c15 ]

Running rcutorture with non-zero fqs_duration module parameter in a
kernel built with CONFIG_PREEMPTION=y results in the following splat:

BUG: using __this_cpu_read() in preemptible [00000000]
code: rcu_torture_fqs/398
caller is __this_cpu_preempt_check+0x13/0x20
CPU: 3 PID: 398 Comm: rcu_torture_fqs Not tainted 6.0.0-rc1-yoctodev-standard+
Call Trace:
&lt;TASK&gt;
dump_stack_lvl+0x5b/0x86
dump_stack+0x10/0x16
check_preemption_disabled+0xe5/0xf0
__this_cpu_preempt_check+0x13/0x20
rcu_force_quiescent_state.part.0+0x1c/0x170
rcu_force_quiescent_state+0x1e/0x30
rcu_torture_fqs+0xca/0x160
? rcu_torture_boost+0x430/0x430
kthread+0x192/0x1d0
? kthread_complete_and_exit+0x30/0x30
ret_from_fork+0x22/0x30
&lt;/TASK&gt;

The problem is that rcu_force_quiescent_state() uses __this_cpu_read()
in preemptible code instead of the proper raw_cpu_read().  This commit
therefore changes __this_cpu_read() to raw_cpu_read().

Signed-off-by: Zqiang &lt;qiang1.zhang@intel.com&gt;
Reviewed-by: Joel Fernandes (Google) &lt;joel@joelfernandes.org&gt;
Signed-off-by: Paul E. McKenney &lt;paulmck@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>tracing/hist: Fix issue of losting command info in error_log</title>
<updated>2022-12-31T12:14:31Z</updated>
<author>
<name>Zheng Yejian</name>
<email>zhengyejian1@huawei.com</email>
</author>
<published>2022-12-07T13:53:26Z</published>
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<id>urn:sha1:a44102d36a7a23c909e2d2c7dc1574c059ff78e1</id>
<content type='text'>
[ Upstream commit 608c6ed3337850c767ab0dd6c583477922233e29 ]

When input some constructed invalid 'trigger' command, command info
in 'error_log' are lost [1].

The root cause is that there is a path that event_hist_trigger_parse()
is recursely called once and 'last_cmd' which save origin command is
cleared, then later calling of hist_err() will no longer record origin
command info:

  event_hist_trigger_parse() {
    last_cmd_set()  // &lt;1&gt; 'last_cmd' save origin command here at first
    create_actions() {
      onmatch_create() {
        action_create() {
          trace_action_create() {
            trace_action_create_field_var() {
              create_field_var_hist() {
                event_hist_trigger_parse() {  // &lt;2&gt; recursely called once
                  hist_err_clear()  // &lt;3&gt; 'last_cmd' is cleared here
                }
                hist_err()  // &lt;4&gt; No longer find origin command!!!

Since 'glob' is empty string while running into the recurse call, we
can trickly check it and bypass the call of hist_err_clear() to solve it.

[1]
 # cd /sys/kernel/tracing
 # echo "my_synth_event int v1; int v2; int v3;" &gt;&gt; synthetic_events
 # echo 'hist:keys=pid' &gt;&gt; events/sched/sched_waking/trigger
 # echo "hist:keys=next_pid:onmatch(sched.sched_waking).my_synth_event(\
pid,pid1)" &gt;&gt; events/sched/sched_switch/trigger
 # cat error_log
[  8.405018] hist:sched:sched_switch: error: Couldn't find synthetic event
  Command:
hist:keys=next_pid:onmatch(sched.sched_waking).my_synth_event(pid,pid1)
                                                          ^
[  8.816902] hist:sched:sched_switch: error: Couldn't find field
  Command:
hist:keys=next_pid:onmatch(sched.sched_waking).my_synth_event(pid,pid1)
                          ^
[  8.816902] hist:sched:sched_switch: error: Couldn't parse field variable
  Command:
hist:keys=next_pid:onmatch(sched.sched_waking).my_synth_event(pid,pid1)
                          ^
[  8.999880] : error: Couldn't find field
  Command:
           ^
[  8.999880] : error: Couldn't parse field variable
  Command:
           ^
[  8.999880] : error: Couldn't find field
  Command:
           ^
[  8.999880] : error: Couldn't create histogram for field
  Command:
           ^

Link: https://lore.kernel.org/linux-trace-kernel/20221207135326.3483216-1-zhengyejian1@huawei.com

Cc: &lt;mhiramat@kernel.org&gt;
Cc: &lt;zanussi@kernel.org&gt;
Fixes: f404da6e1d46 ("tracing: Add 'last error' error facility for hist triggers")
Signed-off-by: Zheng Yejian &lt;zhengyejian1@huawei.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>padata: Fix list iterator in padata_do_serial()</title>
<updated>2022-12-31T12:14:24Z</updated>
<author>
<name>Daniel Jordan</name>
<email>daniel.m.jordan@oracle.com</email>
</author>
<published>2022-11-17T01:28:04Z</published>
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<id>urn:sha1:26c0f7e1ac9249b4876affd6db020c745bc877b0</id>
<content type='text'>
[ Upstream commit 57ddfecc72a6c9941d159543e1c0c0a74fe9afdd ]

list_for_each_entry_reverse() assumes that the iterated list is nonempty
and that every list_head is embedded in the same type, but its use in
padata_do_serial() breaks both rules.

This doesn't cause any issues now because padata_priv and padata_list
happen to have their list fields at the same offset, but we really
shouldn't be relying on that.

Fixes: bfde23ce200e ("padata: unbind parallel jobs from specific CPUs")
Signed-off-by: Daniel Jordan &lt;daniel.m.jordan@oracle.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>padata: Always leave BHs disabled when running -&gt;parallel()</title>
<updated>2022-12-31T12:14:24Z</updated>
<author>
<name>Daniel Jordan</name>
<email>daniel.m.jordan@oracle.com</email>
</author>
<published>2022-11-17T01:28:02Z</published>
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<id>urn:sha1:17afa98bccec4f52203508b3f49b5f948c6fd6ac</id>
<content type='text'>
[ Upstream commit 34c3a47d20ae55b3600fed733bf96eafe9c500d5 ]

A deadlock can happen when an overloaded system runs -&gt;parallel() in the
context of the current task:

    padata_do_parallel
      -&gt;parallel()
        pcrypt_aead_enc/dec
          padata_do_serial
            spin_lock(&amp;reorder-&gt;lock) // BHs still enabled
              &lt;interrupt&gt;
                ...
                  __do_softirq
                    ...
                      padata_do_serial
                        spin_lock(&amp;reorder-&gt;lock)

It's a bug for BHs to be on in _do_serial as Steffen points out, so
ensure they're off in the "current task" case like they are in
padata_parallel_worker to avoid this situation.

Reported-by: syzbot+bc05445bc14148d51915@syzkaller.appspotmail.com
Fixes: 4611ce224688 ("padata: allocate work structures for parallel jobs from a pool")
Signed-off-by: Daniel Jordan &lt;daniel.m.jordan@oracle.com&gt;
Acked-by: Steffen Klassert &lt;steffen.klassert@secunet.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>bpf: Do not zero-extend kfunc return values</title>
<updated>2022-12-31T12:14:18Z</updated>
<author>
<name>Björn Töpel</name>
<email>bjorn@rivosinc.com</email>
</author>
<published>2022-12-07T10:35:40Z</published>
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<id>urn:sha1:e515881adeb111db8bdbc3a0d19f6bfa2b3bffb9</id>
<content type='text'>
[ Upstream commit d35af0a7feb077c43ff0233bba5a8c6e75b73e35 ]

In BPF all global functions, and BPF helpers return a 64-bit
value. For kfunc calls, this is not the case, and they can return
e.g. 32-bit values.

The return register R0 for kfuncs calls can therefore be marked as
subreg_def != DEF_NOT_SUBREG. In general, if a register is marked with
subreg_def != DEF_NOT_SUBREG, some archs (where bpf_jit_needs_zext()
returns true) require the verifier to insert explicit zero-extension
instructions.

For kfuncs calls, however, the caller should do sign/zero extension
for return values. In other words, the compiler is responsible to
insert proper instructions, not the verifier.

An example, provided by Yonghong Song:

$ cat t.c
extern unsigned foo(void);
unsigned bar1(void) {
     return foo();
}
unsigned bar2(void) {
     if (foo()) return 10; else return 20;
}

$ clang -target bpf -mcpu=v3 -O2 -c t.c &amp;&amp; llvm-objdump -d t.o
t.o:    file format elf64-bpf

Disassembly of section .text:

0000000000000000 &lt;bar1&gt;:
	0:       85 10 00 00 ff ff ff ff call -0x1
	1:       95 00 00 00 00 00 00 00 exit

0000000000000010 &lt;bar2&gt;:
	2:       85 10 00 00 ff ff ff ff call -0x1
	3:       bc 01 00 00 00 00 00 00 w1 = w0
	4:       b4 00 00 00 14 00 00 00 w0 = 0x14
	5:       16 01 01 00 00 00 00 00 if w1 == 0x0 goto +0x1 &lt;LBB1_2&gt;
	6:       b4 00 00 00 0a 00 00 00 w0 = 0xa

0000000000000038 &lt;LBB1_2&gt;:
	7:       95 00 00 00 00 00 00 00 exit

If the return value of 'foo()' is used in the BPF program, the proper
zero-extension will be done.

Currently, the verifier correctly marks, say, a 32-bit return value as
subreg_def != DEF_NOT_SUBREG, but will fail performing the actual
zero-extension, due to a verifier bug in
opt_subreg_zext_lo32_rnd_hi32(). load_reg is not properly set to R0,
and the following path will be taken:

		if (WARN_ON(load_reg == -1)) {
			verbose(env, "verifier bug. zext_dst is set, but no reg is defined\n");
			return -EFAULT;
		}

A longer discussion from v1 can be found in the link below.

Correct the verifier by avoiding doing explicit zero-extension of R0
for kfunc calls. Note that R0 will still be marked as a sub-register
for return values smaller than 64-bit.

Fixes: 83a2881903f3 ("bpf: Account for BPF_FETCH in insn_has_def32()")
Link: https://lore.kernel.org/bpf/20221202103620.1915679-1-bjorn@kernel.org/
Suggested-by: Yonghong Song &lt;yhs@meta.com&gt;
Signed-off-by: Björn Töpel &lt;bjorn@rivosinc.com&gt;
Acked-by: Yonghong Song &lt;yhs@fb.com&gt;
Link: https://lore.kernel.org/r/20221207103540.396496-1-bjorn@kernel.org
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>blktrace: Fix output non-blktrace event when blk_classic option enabled</title>
<updated>2022-12-31T12:14:18Z</updated>
<author>
<name>Yang Jihong</name>
<email>yangjihong1@huawei.com</email>
</author>
<published>2022-11-22T04:04:10Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=ce61a877c79f698b4bf1878b124f5d14cc99b650'/>
<id>urn:sha1:ce61a877c79f698b4bf1878b124f5d14cc99b650</id>
<content type='text'>
[ Upstream commit f596da3efaf4130ff61cd029558845808df9bf99 ]

When the blk_classic option is enabled, non-blktrace events must be
filtered out. Otherwise, events of other types are output in the blktrace
classic format, which is unexpected.

The problem can be triggered in the following ways:

  # echo 1 &gt; /sys/kernel/debug/tracing/options/blk_classic
  # echo 1 &gt; /sys/kernel/debug/tracing/events/enable
  # echo blk &gt; /sys/kernel/debug/tracing/current_tracer
  # cat /sys/kernel/debug/tracing/trace_pipe

Fixes: c71a89615411 ("blktrace: add ftrace plugin")
Signed-off-by: Yang Jihong &lt;yangjihong1@huawei.com&gt;
Link: https://lore.kernel.org/r/20221122040410.85113-1-yangjihong1@huawei.com
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>bpf: propagate precision across all frames, not just the last one</title>
<updated>2022-12-31T12:14:09Z</updated>
<author>
<name>Andrii Nakryiko</name>
<email>andrii@kernel.org</email>
</author>
<published>2022-11-04T16:36:45Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=322c7415e77e3e05f91beb8765fb01935dcc88ff'/>
<id>urn:sha1:322c7415e77e3e05f91beb8765fb01935dcc88ff</id>
<content type='text'>
[ Upstream commit 529409ea92d590659be487ba0839710329bd8074 ]

When equivalent completed state is found and it has additional precision
restrictions, BPF verifier propagates precision to
currently-being-verified state chain (i.e., including parent states) so
that if some of the states in the chain are not yet completed, necessary
precision restrictions are enforced.

Unfortunately, right now this happens only for the last frame (deepest
active subprogram's frame), not all the frames. This can lead to
incorrect matching of states due to missing precision marker. Currently
this doesn't seem possible as BPF verifier forces everything to precise
when validated BPF program has any subprograms. But with the next patch
lifting this restriction, this becomes problematic.

In fact, without this fix, we'll start getting failure in one of the
existing test_verifier test cases:

  #906/p precise: cross frame pruning FAIL
  Unexpected success to load!
  verification time 48 usec
  stack depth 0+0
  processed 26 insns (limit 1000000) max_states_per_insn 3 total_states 17 peak_states 17 mark_read 8

This patch adds precision propagation across all frames.

Fixes: a3ce685dd01a ("bpf: fix precision tracking")
Signed-off-by: Andrii Nakryiko &lt;andrii@kernel.org&gt;
Link: https://lore.kernel.org/r/20221104163649.121784-3-andrii@kernel.org
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
</feed>
