<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/tools/testing/selftests/bpf, branch v4.18</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>bpf, sockmap: fix cork timeout for select due to epipe</title>
<updated>2018-08-08T19:06:17+00:00</updated>
<author>
<name>Daniel Borkmann</name>
<email>daniel@iogearbox.net</email>
</author>
<published>2018-08-08T17:23:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=3c6ed988fd8b66eec8e5ab2b624818865d2712ca'/>
<id>3c6ed988fd8b66eec8e5ab2b624818865d2712ca</id>
<content type='text'>
I ran into the same issue as a009f1f396d0 ("selftests/bpf:
test_sockmap, timing improvements") where I had a broken
pipe error on the socket due to remote end timing out on
select and then shutting down it's sockets while the other
side was still sending. We may need to do a bigger rework
in general on the test_sockmap.c, but for now increase it
to a more suitable timeout.

Fixes: a18fda1a62c3 ("bpf: reduce runtime of test_sockmap tests")
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Acked-by: John Fastabend &lt;john.fastabend@gmail.com&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
I ran into the same issue as a009f1f396d0 ("selftests/bpf:
test_sockmap, timing improvements") where I had a broken
pipe error on the socket due to remote end timing out on
select and then shutting down it's sockets while the other
side was still sending. We may need to do a bigger rework
in general on the test_sockmap.c, but for now increase it
to a more suitable timeout.

Fixes: a18fda1a62c3 ("bpf: reduce runtime of test_sockmap tests")
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Acked-by: John Fastabend &lt;john.fastabend@gmail.com&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>selftests/bpf: update test_lwt_seg6local.sh according to iproute2</title>
<updated>2018-08-03T08:19:33+00:00</updated>
<author>
<name>Mathieu Xhonneux</name>
<email>m.xhonneux@gmail.com</email>
</author>
<published>2018-08-01T15:34:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8c85cbdf371f9ddf256ecc5d9548b26ee8fcfe2f'/>
<id>8c85cbdf371f9ddf256ecc5d9548b26ee8fcfe2f</id>
<content type='text'>
The shell file for test_lwt_seg6local contains an early iproute2 syntax
for installing a seg6local End.BPF route. iproute2 support for this
feature has recently been upstreamed, but with an additional keyword
required. This patch updates test_lwt_seg6local.sh to the definitive
iproute2 syntax

Signed-off-by: Mathieu Xhonneux &lt;m.xhonneux@gmail.com&gt;
Acked-by: Yonghong Song &lt;yhs@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The shell file for test_lwt_seg6local contains an early iproute2 syntax
for installing a seg6local End.BPF route. iproute2 support for this
feature has recently been upstreamed, but with an additional keyword
required. This patch updates test_lwt_seg6local.sh to the definitive
iproute2 syntax

Signed-off-by: Mathieu Xhonneux &lt;m.xhonneux@gmail.com&gt;
Acked-by: Yonghong Song &lt;yhs@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bpf: btf: Use exact btf value_size match in map_check_btf()</title>
<updated>2018-07-27T01:45:49+00:00</updated>
<author>
<name>Martin KaFai Lau</name>
<email>kafai@fb.com</email>
</author>
<published>2018-07-26T16:57:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5f300e8004cb80182a24c0fa488218a4a43e6aac'/>
<id>5f300e8004cb80182a24c0fa488218a4a43e6aac</id>
<content type='text'>
The current map_check_btf() in BPF_MAP_TYPE_ARRAY rejects
'&gt; map-&gt;value_size' to ensure map_seq_show_elem() will not
access things beyond an array element.

Yonghong suggested that using '!=' is a more correct
check.  The 8 bytes round_up on value_size is stored
in array-&gt;elem_size.  Hence, using '!=' on map-&gt;value_size
is a proper check.

This patch also adds new tests to check the btf array
key type and value type.  Two of these new tests verify
the btf's value_size (the change in this patch).

It also fixes two existing tests that wrongly encoded
a btf's type size (pprint_test) and the value_type_id (in one
of the raw_tests[]).  However, that do not affect these two
BTF verification tests before or after this test changes.
These two tests mainly failed at array creation time after
this patch.

Fixes: a26ca7c982cb ("bpf: btf: Add pretty print support to the basic arraymap")
Suggested-by: Yonghong Song &lt;yhs@fb.com&gt;
Acked-by: Yonghong Song &lt;yhs@fb.com&gt;
Signed-off-by: Martin KaFai Lau &lt;kafai@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The current map_check_btf() in BPF_MAP_TYPE_ARRAY rejects
'&gt; map-&gt;value_size' to ensure map_seq_show_elem() will not
access things beyond an array element.

Yonghong suggested that using '!=' is a more correct
check.  The 8 bytes round_up on value_size is stored
in array-&gt;elem_size.  Hence, using '!=' on map-&gt;value_size
is a proper check.

This patch also adds new tests to check the btf array
key type and value type.  Two of these new tests verify
the btf's value_size (the change in this patch).

It also fixes two existing tests that wrongly encoded
a btf's type size (pprint_test) and the value_type_id (in one
of the raw_tests[]).  However, that do not affect these two
BTF verification tests before or after this test changes.
These two tests mainly failed at array creation time after
this patch.

Fixes: a26ca7c982cb ("bpf: btf: Add pretty print support to the basic arraymap")
Suggested-by: Yonghong Song &lt;yhs@fb.com&gt;
Acked-by: Yonghong Song &lt;yhs@fb.com&gt;
Signed-off-by: Martin KaFai Lau &lt;kafai@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bpf: Introduce BPF_ANNOTATE_KV_PAIR</title>
<updated>2018-07-25T04:57:55+00:00</updated>
<author>
<name>Martin KaFai Lau</name>
<email>kafai@fb.com</email>
</author>
<published>2018-07-24T15:40:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=38d5d3b3d5dbc0e0bb51fa6f7559d0d5a27916f6'/>
<id>38d5d3b3d5dbc0e0bb51fa6f7559d0d5a27916f6</id>
<content type='text'>
This patch introduces BPF_ANNOTATE_KV_PAIR to signal the
bpf loader about the btf key_type and value_type of a bpf map.
Please refer to the changes in test_btf_haskv.c for its usage.
Both iproute2 and libbpf loader will then have the same
convention to find out the map's btf_key_type_id and
btf_value_type_id from a map's name.

Fixes: 8a138aed4a80 ("bpf: btf: Add BTF support to libbpf")
Suggested-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Signed-off-by: Martin KaFai Lau &lt;kafai@fb.com&gt;
Acked-by: Yonghong Song &lt;yhs@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This patch introduces BPF_ANNOTATE_KV_PAIR to signal the
bpf loader about the btf key_type and value_type of a bpf map.
Please refer to the changes in test_btf_haskv.c for its usage.
Both iproute2 and libbpf loader will then have the same
convention to find out the map's btf_key_type_id and
btf_value_type_id from a map's name.

Fixes: 8a138aed4a80 ("bpf: btf: Add BTF support to libbpf")
Suggested-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Signed-off-by: Martin KaFai Lau &lt;kafai@fb.com&gt;
Acked-by: Yonghong Song &lt;yhs@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bpf: btf: Ensure the member-&gt;offset is in the right order</title>
<updated>2018-07-23T23:20:44+00:00</updated>
<author>
<name>Martin KaFai Lau</name>
<email>kafai@fb.com</email>
</author>
<published>2018-07-21T00:38:37+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6283fa38dc8744dc7c2bd2a03bb0478fe42f79fa'/>
<id>6283fa38dc8744dc7c2bd2a03bb0478fe42f79fa</id>
<content type='text'>
This patch ensures the member-&gt;offset of a struct
is in the correct order (i.e the later member's offset cannot
go backward).

The current "pahole -J" BTF encoder does not generate something
like this.  However, checking this can ensure future encoder
will not violate this.

Fixes: 69b693f0aefa ("bpf: btf: Introduce BPF Type Format (BTF)")
Signed-off-by: Martin KaFai Lau &lt;kafai@fb.com&gt;
Acked-by: Yonghong Song &lt;yhs@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This patch ensures the member-&gt;offset of a struct
is in the correct order (i.e the later member's offset cannot
go backward).

The current "pahole -J" BTF encoder does not generate something
like this.  However, checking this can ensure future encoder
will not violate this.

Fixes: 69b693f0aefa ("bpf: btf: Introduce BPF Type Format (BTF)")
Signed-off-by: Martin KaFai Lau &lt;kafai@fb.com&gt;
Acked-by: Yonghong Song &lt;yhs@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bpf: Use option "help" in the llvm-objcopy test</title>
<updated>2018-07-20T08:27:47+00:00</updated>
<author>
<name>Martin KaFai Lau</name>
<email>kafai@fb.com</email>
</author>
<published>2018-07-20T05:34:10+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7c3e8b642bad6669e0023d3d6dedd87b2527a2c8'/>
<id>7c3e8b642bad6669e0023d3d6dedd87b2527a2c8</id>
<content type='text'>
I noticed the "--version" option of the llvm-objcopy command has recently
disappeared from the master llvm branch.  It is currently used as a BTF
support test in tools/testing/selftests/bpf/Makefile.

This patch replaces it with "--help" which should be
less error prone in the future.

Fixes: c0fa1b6c3efc ("bpf: btf: Add BTF tests")
Signed-off-by: Martin KaFai Lau &lt;kafai@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
I noticed the "--version" option of the llvm-objcopy command has recently
disappeared from the master llvm branch.  It is currently used as a BTF
support test in tools/testing/selftests/bpf/Makefile.

This patch replaces it with "--help" which should be
less error prone in the future.

Fixes: c0fa1b6c3efc ("bpf: btf: Add BTF tests")
Signed-off-by: Martin KaFai Lau &lt;kafai@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bpf: test case to check whether src/dst regs got mangled by xadd</title>
<updated>2018-07-19T23:08:06+00:00</updated>
<author>
<name>Daniel Borkmann</name>
<email>daniel@iogearbox.net</email>
</author>
<published>2018-07-19T16:18:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fa47a16b04ad896ea9c10d4fa0caf47dcf47cd00'/>
<id>fa47a16b04ad896ea9c10d4fa0caf47dcf47cd00</id>
<content type='text'>
We currently do not have such a test case in test_verifier selftests
but it's important to test under bpf_jit_enable=1 to make sure JIT
implementations do not mistakenly mess with src/dst reg for xadd/{w,dw}.

Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
We currently do not have such a test case in test_verifier selftests
but it's important to test under bpf_jit_enable=1 to make sure JIT
implementations do not mistakenly mess with src/dst reg for xadd/{w,dw}.

Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>bpf: fix panic due to oob in bpf_prog_test_run_skb</title>
<updated>2018-07-11T23:10:57+00:00</updated>
<author>
<name>Daniel Borkmann</name>
<email>daniel@iogearbox.net</email>
</author>
<published>2018-07-11T13:30:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6e6fddc78323533be570873abb728b7e0ba7e024'/>
<id>6e6fddc78323533be570873abb728b7e0ba7e024</id>
<content type='text'>
sykzaller triggered several panics similar to the below:

  [...]
  [  248.851531] BUG: KASAN: use-after-free in _copy_to_user+0x5c/0x90
  [  248.857656] Read of size 985 at addr ffff8808017ffff2 by task a.out/1425
  [...]
  [  248.865902] CPU: 1 PID: 1425 Comm: a.out Not tainted 4.18.0-rc4+ #13
  [  248.865903] Hardware name: Supermicro SYS-5039MS-H12TRF/X11SSE-F, BIOS 2.1a 03/08/2018
  [  248.865905] Call Trace:
  [  248.865910]  dump_stack+0xd6/0x185
  [  248.865911]  ? show_regs_print_info+0xb/0xb
  [  248.865913]  ? printk+0x9c/0xc3
  [  248.865915]  ? kmsg_dump_rewind_nolock+0xe4/0xe4
  [  248.865919]  print_address_description+0x6f/0x270
  [  248.865920]  kasan_report+0x25b/0x380
  [  248.865922]  ? _copy_to_user+0x5c/0x90
  [  248.865924]  check_memory_region+0x137/0x190
  [  248.865925]  kasan_check_read+0x11/0x20
  [  248.865927]  _copy_to_user+0x5c/0x90
  [  248.865930]  bpf_test_finish.isra.8+0x4f/0xc0
  [  248.865932]  bpf_prog_test_run_skb+0x6a0/0xba0
  [...]

After scrubbing the BPF prog a bit from the noise, turns out it called
bpf_skb_change_head() for the lwt_xmit prog with headroom of 2. Nothing
wrong in that, however, this was run with repeat &gt;&gt; 0 in bpf_prog_test_run_skb()
and the same skb thus keeps changing until the pskb_expand_head() called
from skb_cow() keeps bailing out in atomic alloc context with -ENOMEM.
So upon return we'll basically have 0 headroom left yet blindly do the
__skb_push() of 14 bytes and keep copying data from there in bpf_test_finish()
out of bounds. Fix to check if we have enough headroom and if pskb_expand_head()
fails, bail out with error.

Another bug independent of this fix (but related in triggering above) is
that BPF_PROG_TEST_RUN should be reworked to reset the skb/xdp buffer to
it's original state from input as otherwise repeating the same test in a
loop won't work for benchmarking when underlying input buffer is getting
changed by the prog each time and reused for the next run leading to
unexpected results.

Fixes: 1cf1cae963c2 ("bpf: introduce BPF_PROG_TEST_RUN command")
Reported-by: syzbot+709412e651e55ed96498@syzkaller.appspotmail.com
Reported-by: syzbot+54f39d6ab58f39720a55@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
sykzaller triggered several panics similar to the below:

  [...]
  [  248.851531] BUG: KASAN: use-after-free in _copy_to_user+0x5c/0x90
  [  248.857656] Read of size 985 at addr ffff8808017ffff2 by task a.out/1425
  [...]
  [  248.865902] CPU: 1 PID: 1425 Comm: a.out Not tainted 4.18.0-rc4+ #13
  [  248.865903] Hardware name: Supermicro SYS-5039MS-H12TRF/X11SSE-F, BIOS 2.1a 03/08/2018
  [  248.865905] Call Trace:
  [  248.865910]  dump_stack+0xd6/0x185
  [  248.865911]  ? show_regs_print_info+0xb/0xb
  [  248.865913]  ? printk+0x9c/0xc3
  [  248.865915]  ? kmsg_dump_rewind_nolock+0xe4/0xe4
  [  248.865919]  print_address_description+0x6f/0x270
  [  248.865920]  kasan_report+0x25b/0x380
  [  248.865922]  ? _copy_to_user+0x5c/0x90
  [  248.865924]  check_memory_region+0x137/0x190
  [  248.865925]  kasan_check_read+0x11/0x20
  [  248.865927]  _copy_to_user+0x5c/0x90
  [  248.865930]  bpf_test_finish.isra.8+0x4f/0xc0
  [  248.865932]  bpf_prog_test_run_skb+0x6a0/0xba0
  [...]

After scrubbing the BPF prog a bit from the noise, turns out it called
bpf_skb_change_head() for the lwt_xmit prog with headroom of 2. Nothing
wrong in that, however, this was run with repeat &gt;&gt; 0 in bpf_prog_test_run_skb()
and the same skb thus keeps changing until the pskb_expand_head() called
from skb_cow() keeps bailing out in atomic alloc context with -ENOMEM.
So upon return we'll basically have 0 headroom left yet blindly do the
__skb_push() of 14 bytes and keep copying data from there in bpf_test_finish()
out of bounds. Fix to check if we have enough headroom and if pskb_expand_head()
fails, bail out with error.

Another bug independent of this fix (but related in triggering above) is
that BPF_PROG_TEST_RUN should be reworked to reset the skb/xdp buffer to
it's original state from input as otherwise repeating the same test in a
loop won't work for benchmarking when underlying input buffer is getting
changed by the prog each time and reused for the next run leading to
unexpected results.

Fixes: 1cf1cae963c2 ("bpf: introduce BPF_PROG_TEST_RUN command")
Reported-by: syzbot+709412e651e55ed96498@syzkaller.appspotmail.com
Reported-by: syzbot+54f39d6ab58f39720a55@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>selftests: bpf: notification about privilege required to run test_lwt_seg6local.sh testing script</title>
<updated>2018-06-26T10:16:36+00:00</updated>
<author>
<name>Jeffrin Jose T</name>
<email>ahiliation@gmail.com</email>
</author>
<published>2018-06-22T21:40:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=dd349c3ffd93d15d01f4f5ace73870ca45ea249d'/>
<id>dd349c3ffd93d15d01f4f5ace73870ca45ea249d</id>
<content type='text'>
This test needs root privilege for it's successful execution.

This patch is atleast used to notify the user about the privilege
the script demands for the  smooth execution of the test.

Signed-off-by: Jeffrin Jose T (Rajagiri SET) &lt;ahiliation@gmail.com&gt;
Acked-by: Song Liu &lt;songliubraving@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This test needs root privilege for it's successful execution.

This patch is atleast used to notify the user about the privilege
the script demands for the  smooth execution of the test.

Signed-off-by: Jeffrin Jose T (Rajagiri SET) &lt;ahiliation@gmail.com&gt;
Acked-by: Song Liu &lt;songliubraving@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>selftests: bpf: notification about privilege required to run test_lirc_mode2.sh testing script</title>
<updated>2018-06-26T10:15:28+00:00</updated>
<author>
<name>Jeffrin Jose T</name>
<email>ahiliation@gmail.com</email>
</author>
<published>2018-06-22T18:54:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b0e4b8bcd48bde31690f066044767475b2e4852b'/>
<id>b0e4b8bcd48bde31690f066044767475b2e4852b</id>
<content type='text'>
The test_lirc_mode2.sh script require root privilege for the successful
execution of the test.

This patch is to notify the user about the privilege the script
demands for the successful execution of the test.

Signed-off-by: Jeffrin Jose T (Rajagiri SET) &lt;ahiliation@gmail.com&gt;
Acked-by: Song Liu &lt;songliubraving@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The test_lirc_mode2.sh script require root privilege for the successful
execution of the test.

This patch is to notify the user about the privilege the script
demands for the successful execution of the test.

Signed-off-by: Jeffrin Jose T (Rajagiri SET) &lt;ahiliation@gmail.com&gt;
Acked-by: Song Liu &lt;songliubraving@fb.com&gt;
Signed-off-by: Daniel Borkmann &lt;daniel@iogearbox.net&gt;
</pre>
</div>
</content>
</entry>
</feed>
