<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/tools/testing, branch v5.4.211</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>selftests/kprobe: Do not test for GRP/ without event failures</title>
<updated>2022-08-25T09:18:34+00:00</updated>
<author>
<name>Steven Rostedt (Google)</name>
<email>rostedt@goodmis.org</email>
</author>
<published>2022-07-12T20:17:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d13b990d4fbecb7497bc42315eaa881522fe11f7'/>
<id>d13b990d4fbecb7497bc42315eaa881522fe11f7</id>
<content type='text'>
[ Upstream commit f5eab65ff2b76449286d18efc7fee3e0b72f7d9b ]

A new feature is added where kprobes (and other probes) do not need to
explicitly state the event name when creating a probe. The event name will
come from what is being attached.

That is:

  # echo 'p:foo/ vfs_read' &gt; kprobe_events

Will no longer error, but instead create an event:

  # cat kprobe_events
 p:foo/p_vfs_read_0 vfs_read

This should not be tested as an error case anymore. Remove it from the
selftest as now this feature "breaks" the selftest as it no longer fails
as expected.

Link: https://lore.kernel.org/all/1656296348-16111-1-git-send-email-quic_linyyuan@quicinc.com/
Link: https://lkml.kernel.org/r/20220712161707.6dc08a14@gandalf.local.home

Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.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 f5eab65ff2b76449286d18efc7fee3e0b72f7d9b ]

A new feature is added where kprobes (and other probes) do not need to
explicitly state the event name when creating a probe. The event name will
come from what is being attached.

That is:

  # echo 'p:foo/ vfs_read' &gt; kprobe_events

Will no longer error, but instead create an event:

  # cat kprobe_events
 p:foo/p_vfs_read_0 vfs_read

This should not be tested as an error case anymore. Remove it from the
selftest as now this feature "breaks" the selftest as it no longer fails
as expected.

Link: https://lore.kernel.org/all/1656296348-16111-1-git-send-email-quic_linyyuan@quicinc.com/
Link: https://lkml.kernel.org/r/20220712161707.6dc08a14@gandalf.local.home

Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>selftests/bpf: fix a test for snprintf() overflow</title>
<updated>2022-08-25T09:17:45+00:00</updated>
<author>
<name>Dan Carpenter</name>
<email>dan.carpenter@oracle.com</email>
</author>
<published>2022-07-19T09:50:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ecbdb2985e086b59faef68329688bc41f89c3398'/>
<id>ecbdb2985e086b59faef68329688bc41f89c3398</id>
<content type='text'>
[ Upstream commit c5d22f4cfe8dfb93f1db0a1e7e2e7ebc41395d98 ]

The snprintf() function returns the number of bytes which *would*
have been copied if there were space.  In other words, it can be
&gt; sizeof(pin_path).

Fixes: c0fa1b6c3efc ("bpf: btf: Add BTF tests")
Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Acked-by: Martin KaFai Lau &lt;kafai@fb.com&gt;
Link: https://lore.kernel.org/r/YtZ+aD/tZMkgOUw+@kili
Signed-off-by: Alexei Starovoitov &lt;ast@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 c5d22f4cfe8dfb93f1db0a1e7e2e7ebc41395d98 ]

The snprintf() function returns the number of bytes which *would*
have been copied if there were space.  In other words, it can be
&gt; sizeof(pin_path).

Fixes: c0fa1b6c3efc ("bpf: btf: Add BTF tests")
Signed-off-by: Dan Carpenter &lt;dan.carpenter@oracle.com&gt;
Acked-by: Martin KaFai Lau &lt;kafai@fb.com&gt;
Link: https://lore.kernel.org/r/YtZ+aD/tZMkgOUw+@kili
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>selftests: timers: clocksource-switch: fix passing errors from child</title>
<updated>2022-08-25T09:17:43+00:00</updated>
<author>
<name>Wolfram Sang</name>
<email>wsa+renesas@sang-engineering.com</email>
</author>
<published>2022-07-13T20:46:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8cf6e837dcfc73a068225b95c6470b98045c6be2'/>
<id>8cf6e837dcfc73a068225b95c6470b98045c6be2</id>
<content type='text'>
[ Upstream commit 4d8f52ac5fa9eede7b7aa2f2d67c841d9eeb655f ]

The return value from system() is a waitpid-style integer. Do not return
it directly because with the implicit masking in exit() it will always
return 0. Access it with appropriate macros to really pass on errors.

Fixes: 7290ce1423c3 ("selftests/timers: Add clocksource-switch test from timetest suite")
Signed-off-by: Wolfram Sang &lt;wsa+renesas@sang-engineering.com&gt;
Acked-by: John Stultz &lt;jstultz@google.com&gt;
Signed-off-by: Shuah Khan &lt;skhan@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 4d8f52ac5fa9eede7b7aa2f2d67c841d9eeb655f ]

The return value from system() is a waitpid-style integer. Do not return
it directly because with the implicit masking in exit() it will always
return 0. Access it with appropriate macros to really pass on errors.

Fixes: 7290ce1423c3 ("selftests/timers: Add clocksource-switch test from timetest suite")
Signed-off-by: Wolfram Sang &lt;wsa+renesas@sang-engineering.com&gt;
Acked-by: John Stultz &lt;jstultz@google.com&gt;
Signed-off-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>selftests: timers: valid-adjtimex: build fix for newer toolchains</title>
<updated>2022-08-25T09:17:43+00:00</updated>
<author>
<name>Wolfram Sang</name>
<email>wsa+renesas@sang-engineering.com</email>
</author>
<published>2022-07-13T20:46:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2f243fe8db214d9c3f682ab60d05fe5792f7e922'/>
<id>2f243fe8db214d9c3f682ab60d05fe5792f7e922</id>
<content type='text'>
[ Upstream commit 9a162977d20436be5678a8e21a8e58eb4616d86a ]

Toolchains with an include file 'sys/timex.h' based on 3.18 will have a
'clock_adjtime' definition added, so it can't be static in the code:

valid-adjtimex.c:43:12: error: static declaration of ‘clock_adjtime’ follows non-static declaration

Fixes: e03a58c320e1 ("kselftests: timers: Add adjtimex SETOFFSET validity tests")
Signed-off-by: Wolfram Sang &lt;wsa+renesas@sang-engineering.com&gt;
Acked-by: John Stultz &lt;jstultz@google.com&gt;
Signed-off-by: Shuah Khan &lt;skhan@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 9a162977d20436be5678a8e21a8e58eb4616d86a ]

Toolchains with an include file 'sys/timex.h' based on 3.18 will have a
'clock_adjtime' definition added, so it can't be static in the code:

valid-adjtimex.c:43:12: error: static declaration of ‘clock_adjtime’ follows non-static declaration

Fixes: e03a58c320e1 ("kselftests: timers: Add adjtimex SETOFFSET validity tests")
Signed-off-by: Wolfram Sang &lt;wsa+renesas@sang-engineering.com&gt;
Acked-by: John Stultz &lt;jstultz@google.com&gt;
Signed-off-by: Shuah Khan &lt;skhan@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>selftests: KVM: Handle compiler optimizations in ucall</title>
<updated>2022-08-11T10:57:52+00:00</updated>
<author>
<name>Raghavendra Rao Ananta</name>
<email>rananta@google.com</email>
</author>
<published>2022-06-15T18:57:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=17c2356e467f1382addc5522dc02073d2326bc3b'/>
<id>17c2356e467f1382addc5522dc02073d2326bc3b</id>
<content type='text'>
[ Upstream commit 9e2f6498efbbc880d7caa7935839e682b64fe5a6 ]

The selftests, when built with newer versions of clang, is found
to have over optimized guests' ucall() function, and eliminating
the stores for uc.cmd (perhaps due to no immediate readers). This
resulted in the userspace side always reading a value of '0', and
causing multiple test failures.

As a result, prevent the compiler from optimizing the stores in
ucall() with WRITE_ONCE().

Suggested-by: Ricardo Koller &lt;ricarkol@google.com&gt;
Suggested-by: Reiji Watanabe &lt;reijiw@google.com&gt;
Signed-off-by: Raghavendra Rao Ananta &lt;rananta@google.com&gt;
Message-Id: &lt;20220615185706.1099208-1-rananta@google.com&gt;
Reviewed-by: Andrew Jones &lt;drjones@redhat.com&gt;
Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.com&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 9e2f6498efbbc880d7caa7935839e682b64fe5a6 ]

The selftests, when built with newer versions of clang, is found
to have over optimized guests' ucall() function, and eliminating
the stores for uc.cmd (perhaps due to no immediate readers). This
resulted in the userspace side always reading a value of '0', and
causing multiple test failures.

As a result, prevent the compiler from optimizing the stores in
ucall() with WRITE_ONCE().

Suggested-by: Ricardo Koller &lt;ricarkol@google.com&gt;
Suggested-by: Reiji Watanabe &lt;reijiw@google.com&gt;
Signed-off-by: Raghavendra Rao Ananta &lt;rananta@google.com&gt;
Message-Id: &lt;20220615185706.1099208-1-rananta@google.com&gt;
Reviewed-by: Andrew Jones &lt;drjones@redhat.com&gt;
Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>selftests/bpf: Fix "dubious pointer arithmetic" test</title>
<updated>2022-08-11T10:57:52+00:00</updated>
<author>
<name>Jean-Philippe Brucker</name>
<email>jean-philippe@linaro.org</email>
</author>
<published>2022-08-03T14:50:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6098562ed9df1babcc0ba5b89c4fb47715ba3f72'/>
<id>6098562ed9df1babcc0ba5b89c4fb47715ba3f72</id>
<content type='text'>
commit 3615bdf6d9b19db12b1589861609b4f1c6a8d303 upstream.

The verifier trace changed following a bugfix. After checking the 64-bit
sign, only the upper bit mask is known, not bit 31. Update the test
accordingly.

Signed-off-by: Jean-Philippe Brucker &lt;jean-philippe@linaro.org&gt;
Acked-by: John Fastabend &lt;john.fastabend@gmail.com&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Signed-off-by: Ovidiu Panait &lt;ovidiu.panait@windriver.com&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 3615bdf6d9b19db12b1589861609b4f1c6a8d303 upstream.

The verifier trace changed following a bugfix. After checking the 64-bit
sign, only the upper bit mask is known, not bit 31. Update the test
accordingly.

Signed-off-by: Jean-Philippe Brucker &lt;jean-philippe@linaro.org&gt;
Acked-by: John Fastabend &lt;john.fastabend@gmail.com&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Signed-off-by: Ovidiu Panait &lt;ovidiu.panait@windriver.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>selftests/bpf: Fix test_align verifier log patterns</title>
<updated>2022-08-11T10:57:52+00:00</updated>
<author>
<name>Stanislav Fomichev</name>
<email>sdf@google.com</email>
</author>
<published>2022-08-03T14:50:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6a9b3f0f3bad4ca6421f8c20e1dde9839699db0f'/>
<id>6a9b3f0f3bad4ca6421f8c20e1dde9839699db0f</id>
<content type='text'>
commit 5366d2269139ba8eb6a906d73a0819947e3e4e0a upstream.

Commit 294f2fc6da27 ("bpf: Verifer, adjust_scalar_min_max_vals to always
call update_reg_bounds()") changed the way verifier logs some of its state,
adjust the test_align accordingly. Where possible, I tried to not copy-paste
the entire log line and resorted to dropping the last closing brace instead.

Fixes: 294f2fc6da27 ("bpf: Verifer, adjust_scalar_min_max_vals to always call update_reg_bounds()")
Signed-off-by: Stanislav Fomichev &lt;sdf@google.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Link: https://lore.kernel.org/bpf/20200515194904.229296-1-sdf@google.com
Signed-off-by: Ovidiu Panait &lt;ovidiu.panait@windriver.com&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 5366d2269139ba8eb6a906d73a0819947e3e4e0a upstream.

Commit 294f2fc6da27 ("bpf: Verifer, adjust_scalar_min_max_vals to always
call update_reg_bounds()") changed the way verifier logs some of its state,
adjust the test_align accordingly. Where possible, I tried to not copy-paste
the entire log line and resorted to dropping the last closing brace instead.

Fixes: 294f2fc6da27 ("bpf: Verifer, adjust_scalar_min_max_vals to always call update_reg_bounds()")
Signed-off-by: Stanislav Fomichev &lt;sdf@google.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Link: https://lore.kernel.org/bpf/20200515194904.229296-1-sdf@google.com
Signed-off-by: Ovidiu Panait &lt;ovidiu.panait@windriver.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bpf: Test_verifier, #70 error message updates for 32-bit right shift</title>
<updated>2022-08-11T10:57:51+00:00</updated>
<author>
<name>John Fastabend</name>
<email>john.fastabend@gmail.com</email>
</author>
<published>2022-08-03T14:50:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=9d6f67365d9cdb389fbdac2bb5b00e59e345930e'/>
<id>9d6f67365d9cdb389fbdac2bb5b00e59e345930e</id>
<content type='text'>
commit aa131ed44ae1d76637f0dbec33cfcf9115af9bc3 upstream.

After changes to add update_reg_bounds after ALU ops and adding ALU32
bounds tracking the error message is changed in the 32-bit right shift
tests.

Test "#70/u bounds check after 32-bit right shift with 64-bit input FAIL"
now fails with,

Unexpected error message!
	EXP: R0 invalid mem access
	RES: func#0 @0

7: (b7) r1 = 2
8: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=invP2 R10=fp0 fp-8_w=mmmmmmmm
8: (67) r1 &lt;&lt;= 31
9: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=invP4294967296 R10=fp0 fp-8_w=mmmmmmmm
9: (74) w1 &gt;&gt;= 31
10: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=invP0 R10=fp0 fp-8_w=mmmmmmmm
10: (14) w1 -= 2
11: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=invP4294967294 R10=fp0 fp-8_w=mmmmmmmm
11: (0f) r0 += r1
math between map_value pointer and 4294967294 is not allowed

And test "#70/p bounds check after 32-bit right shift with 64-bit input
FAIL" now fails with,

Unexpected error message!
	EXP: R0 invalid mem access
	RES: func#0 @0

7: (b7) r1 = 2
8: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=inv2 R10=fp0 fp-8_w=mmmmmmmm
8: (67) r1 &lt;&lt;= 31
9: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=inv4294967296 R10=fp0 fp-8_w=mmmmmmmm
9: (74) w1 &gt;&gt;= 31
10: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=inv0 R10=fp0 fp-8_w=mmmmmmmm
10: (14) w1 -= 2
11: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=inv4294967294 R10=fp0 fp-8_w=mmmmmmmm
11: (0f) r0 += r1
last_idx 11 first_idx 0
regs=2 stack=0 before 10: (14) w1 -= 2
regs=2 stack=0 before 9: (74) w1 &gt;&gt;= 31
regs=2 stack=0 before 8: (67) r1 &lt;&lt;= 31
regs=2 stack=0 before 7: (b7) r1 = 2
math between map_value pointer and 4294967294 is not allowed

Before this series we did not trip the "math between map_value pointer..."
error because check_reg_sane_offset is never called in
adjust_ptr_min_max_vals(). Instead we have a register state that looks
like this at line 11*,

11: R0_w=map_value(id=0,off=0,ks=8,vs=8,
                   smin_value=0,smax_value=0,
                   umin_value=0,umax_value=0,
                   var_off=(0x0; 0x0))
    R1_w=invP(id=0,
              smin_value=0,smax_value=4294967295,
              umin_value=0,umax_value=4294967295,
              var_off=(0xfffffffe; 0x0))
    R10=fp(id=0,off=0,
           smin_value=0,smax_value=0,
           umin_value=0,umax_value=0,
           var_off=(0x0; 0x0)) fp-8_w=mmmmmmmm
11: (0f) r0 += r1

In R1 'smin_val != smax_val' yet we have a tnum_const as seen
by 'var_off(0xfffffffe; 0x0))' with a 0x0 mask. So we hit this check
in adjust_ptr_min_max_vals()

 if ((known &amp;&amp; (smin_val != smax_val || umin_val != umax_val)) ||
      smin_val &gt; smax_val || umin_val &gt; umax_val) {
       /* Taint dst register if offset had invalid bounds derived from
        * e.g. dead branches.
        */
       __mark_reg_unknown(env, dst_reg);
       return 0;
 }

So we don't throw an error here and instead only throw an error
later in the verification when the memory access is made.

The root cause in verifier without alu32 bounds tracking is having
'umin_value = 0' and 'umax_value = U64_MAX' from BPF_SUB which we set
when 'umin_value &lt; umax_val' here,

 if (dst_reg-&gt;umin_value &lt; umax_val) {
    /* Overflow possible, we know nothing */
    dst_reg-&gt;umin_value = 0;
    dst_reg-&gt;umax_value = U64_MAX;
 } else { ...}

Later in adjust_calar_min_max_vals we previously did a
coerce_reg_to_size() which will clamp the U64_MAX to U32_MAX by
truncating to 32bits. But either way without a call to update_reg_bounds
the less precise bounds tracking will fall out of the alu op
verification.

After latest changes we now exit adjust_scalar_min_max_vals with the
more precise umin value, due to zero extension propogating bounds from
alu32 bounds into alu64 bounds and then calling update_reg_bounds.
This then causes the verifier to trigger an earlier error and we get
the error in the output above.

This patch updates tests to reflect new error message.

* I have a local patch to print entire verifier state regardless if we
 believe it is a constant so we can get a full picture of the state.
 Usually if tnum_is_const() then bounds are also smin=smax, etc. but
 this is not always true and is a bit subtle. Being able to see these
 states helps understand dataflow imo. Let me know if we want something
 similar upstream.

Signed-off-by: John Fastabend &lt;john.fastabend@gmail.com&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Link: https://lore.kernel.org/bpf/158507161475.15666.3061518385241144063.stgit@john-Precision-5820-Tower
Signed-off-by: Ovidiu Panait &lt;ovidiu.panait@windriver.com&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 aa131ed44ae1d76637f0dbec33cfcf9115af9bc3 upstream.

After changes to add update_reg_bounds after ALU ops and adding ALU32
bounds tracking the error message is changed in the 32-bit right shift
tests.

Test "#70/u bounds check after 32-bit right shift with 64-bit input FAIL"
now fails with,

Unexpected error message!
	EXP: R0 invalid mem access
	RES: func#0 @0

7: (b7) r1 = 2
8: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=invP2 R10=fp0 fp-8_w=mmmmmmmm
8: (67) r1 &lt;&lt;= 31
9: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=invP4294967296 R10=fp0 fp-8_w=mmmmmmmm
9: (74) w1 &gt;&gt;= 31
10: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=invP0 R10=fp0 fp-8_w=mmmmmmmm
10: (14) w1 -= 2
11: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=invP4294967294 R10=fp0 fp-8_w=mmmmmmmm
11: (0f) r0 += r1
math between map_value pointer and 4294967294 is not allowed

And test "#70/p bounds check after 32-bit right shift with 64-bit input
FAIL" now fails with,

Unexpected error message!
	EXP: R0 invalid mem access
	RES: func#0 @0

7: (b7) r1 = 2
8: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=inv2 R10=fp0 fp-8_w=mmmmmmmm
8: (67) r1 &lt;&lt;= 31
9: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=inv4294967296 R10=fp0 fp-8_w=mmmmmmmm
9: (74) w1 &gt;&gt;= 31
10: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=inv0 R10=fp0 fp-8_w=mmmmmmmm
10: (14) w1 -= 2
11: R0_w=map_value(id=0,off=0,ks=8,vs=8,imm=0) R1_w=inv4294967294 R10=fp0 fp-8_w=mmmmmmmm
11: (0f) r0 += r1
last_idx 11 first_idx 0
regs=2 stack=0 before 10: (14) w1 -= 2
regs=2 stack=0 before 9: (74) w1 &gt;&gt;= 31
regs=2 stack=0 before 8: (67) r1 &lt;&lt;= 31
regs=2 stack=0 before 7: (b7) r1 = 2
math between map_value pointer and 4294967294 is not allowed

Before this series we did not trip the "math between map_value pointer..."
error because check_reg_sane_offset is never called in
adjust_ptr_min_max_vals(). Instead we have a register state that looks
like this at line 11*,

11: R0_w=map_value(id=0,off=0,ks=8,vs=8,
                   smin_value=0,smax_value=0,
                   umin_value=0,umax_value=0,
                   var_off=(0x0; 0x0))
    R1_w=invP(id=0,
              smin_value=0,smax_value=4294967295,
              umin_value=0,umax_value=4294967295,
              var_off=(0xfffffffe; 0x0))
    R10=fp(id=0,off=0,
           smin_value=0,smax_value=0,
           umin_value=0,umax_value=0,
           var_off=(0x0; 0x0)) fp-8_w=mmmmmmmm
11: (0f) r0 += r1

In R1 'smin_val != smax_val' yet we have a tnum_const as seen
by 'var_off(0xfffffffe; 0x0))' with a 0x0 mask. So we hit this check
in adjust_ptr_min_max_vals()

 if ((known &amp;&amp; (smin_val != smax_val || umin_val != umax_val)) ||
      smin_val &gt; smax_val || umin_val &gt; umax_val) {
       /* Taint dst register if offset had invalid bounds derived from
        * e.g. dead branches.
        */
       __mark_reg_unknown(env, dst_reg);
       return 0;
 }

So we don't throw an error here and instead only throw an error
later in the verification when the memory access is made.

The root cause in verifier without alu32 bounds tracking is having
'umin_value = 0' and 'umax_value = U64_MAX' from BPF_SUB which we set
when 'umin_value &lt; umax_val' here,

 if (dst_reg-&gt;umin_value &lt; umax_val) {
    /* Overflow possible, we know nothing */
    dst_reg-&gt;umin_value = 0;
    dst_reg-&gt;umax_value = U64_MAX;
 } else { ...}

Later in adjust_calar_min_max_vals we previously did a
coerce_reg_to_size() which will clamp the U64_MAX to U32_MAX by
truncating to 32bits. But either way without a call to update_reg_bounds
the less precise bounds tracking will fall out of the alu op
verification.

After latest changes we now exit adjust_scalar_min_max_vals with the
more precise umin value, due to zero extension propogating bounds from
alu32 bounds into alu64 bounds and then calling update_reg_bounds.
This then causes the verifier to trigger an earlier error and we get
the error in the output above.

This patch updates tests to reflect new error message.

* I have a local patch to print entire verifier state regardless if we
 believe it is a constant so we can get a full picture of the state.
 Usually if tnum_is_const() then bounds are also smin=smax, etc. but
 this is not always true and is a bit subtle. Being able to see these
 states helps understand dataflow imo. Let me know if we want something
 similar upstream.

Signed-off-by: John Fastabend &lt;john.fastabend@gmail.com&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Link: https://lore.kernel.org/bpf/158507161475.15666.3061518385241144063.stgit@john-Precision-5820-Tower
Signed-off-by: Ovidiu Panait &lt;ovidiu.panait@windriver.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>selftests/bpf: Extend verifier and bpf_sock tests for dst_port loads</title>
<updated>2022-08-11T10:57:51+00:00</updated>
<author>
<name>Jakub Sitnicki</name>
<email>jakub@cloudflare.com</email>
</author>
<published>2022-08-03T14:50:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=751f05bc6f955ae3f9aa0385cf2a9a01d21117e6'/>
<id>751f05bc6f955ae3f9aa0385cf2a9a01d21117e6</id>
<content type='text'>
commit 8f50f16ff39dd4e2d43d1548ca66925652f8aff7 upstream.

Add coverage to the verifier tests and tests for reading bpf_sock fields to
ensure that 32-bit, 16-bit, and 8-bit loads from dst_port field are allowed
only at intended offsets and produce expected values.

While 16-bit and 8-bit access to dst_port field is straight-forward, 32-bit
wide loads need be allowed and produce a zero-padded 16-bit value for
backward compatibility.

Signed-off-by: Jakub Sitnicki &lt;jakub@cloudflare.com&gt;
Link: https://lore.kernel.org/r/20220130115518.213259-3-jakub@cloudflare.com
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
[OP: backport to 5.4: cherry-pick verifier changes only]
Signed-off-by: Ovidiu Panait &lt;ovidiu.panait@windriver.com&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 8f50f16ff39dd4e2d43d1548ca66925652f8aff7 upstream.

Add coverage to the verifier tests and tests for reading bpf_sock fields to
ensure that 32-bit, 16-bit, and 8-bit loads from dst_port field are allowed
only at intended offsets and produce expected values.

While 16-bit and 8-bit access to dst_port field is straight-forward, 32-bit
wide loads need be allowed and produce a zero-padded 16-bit value for
backward compatibility.

Signed-off-by: Jakub Sitnicki &lt;jakub@cloudflare.com&gt;
Link: https://lore.kernel.org/r/20220130115518.213259-3-jakub@cloudflare.com
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
[OP: backport to 5.4: cherry-pick verifier changes only]
Signed-off-by: Ovidiu Panait &lt;ovidiu.panait@windriver.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>selftests: forwarding: fix error message in learning_test</title>
<updated>2022-07-12T14:30:49+00:00</updated>
<author>
<name>Vladimir Oltean</name>
<email>vladimir.oltean@nxp.com</email>
</author>
<published>2022-07-03T07:36:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=acb72388aed5ba6b5b1ecbcdd879d3af2069c9f1'/>
<id>acb72388aed5ba6b5b1ecbcdd879d3af2069c9f1</id>
<content type='text'>
[ Upstream commit 83844aacab2015da1dba1df0cc61fc4b4c4e8076 ]

When packets are not received, they aren't received on $host1_if, so the
message talking about the second host not receiving them is incorrect.
Fix it.

Fixes: d4deb01467ec ("selftests: forwarding: Add a test for FDB learning")
Signed-off-by: Vladimir Oltean &lt;vladimir.oltean@nxp.com&gt;
Reviewed-by: Ido Schimmel &lt;idosch@nvidia.com&gt;
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&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 83844aacab2015da1dba1df0cc61fc4b4c4e8076 ]

When packets are not received, they aren't received on $host1_if, so the
message talking about the second host not receiving them is incorrect.
Fix it.

Fixes: d4deb01467ec ("selftests: forwarding: Add a test for FDB learning")
Signed-off-by: Vladimir Oltean &lt;vladimir.oltean@nxp.com&gt;
Reviewed-by: Ido Schimmel &lt;idosch@nvidia.com&gt;
Signed-off-by: Paolo Abeni &lt;pabeni@redhat.com&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
