<feed xmlns='http://www.w3.org/2005/Atom'>
<title>user/sven/linux.git/kernel, branch v5.15.37</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.15.37</id>
<link rel='self' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v5.15.37'/>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/'/>
<updated>2022-05-01T15:22:26Z</updated>
<entry>
<title>bpf: Fix crash due to out of bounds access into reg2btf_ids.</title>
<updated>2022-05-01T15:22:26Z</updated>
<author>
<name>Kumar Kartikeya Dwivedi</name>
<email>memxor@gmail.com</email>
</author>
<published>2022-04-28T23:57:51Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=8c39925e98d498b9531343066ef82ae39e41adae'/>
<id>urn:sha1:8c39925e98d498b9531343066ef82ae39e41adae</id>
<content type='text'>
commit 45ce4b4f9009102cd9f581196d480a59208690c1 upstream

When commit e6ac2450d6de ("bpf: Support bpf program calling kernel function") added
kfunc support, it defined reg2btf_ids as a cheap way to translate the verifier
reg type to the appropriate btf_vmlinux BTF ID, however
commit c25b2ae13603 ("bpf: Replace PTR_TO_XXX_OR_NULL with PTR_TO_XXX | PTR_MAYBE_NULL")
moved the __BPF_REG_TYPE_MAX from the last member of bpf_reg_type enum to after
the base register types, and defined other variants using type flag
composition. However, now, the direct usage of reg-&gt;type to index into
reg2btf_ids may no longer fall into __BPF_REG_TYPE_MAX range, and hence lead to
out of bounds access and kernel crash on dereference of bad pointer.

[backport note: commit 3363bd0cfbb80 ("bpf: Extend kfunc with PTR_TO_CTX, PTR_TO_MEM
 argument support") was introduced after 5.15 and contains an out of bound
 reg2btf_ids access. Since that commit hasn't been backported, this patch
 doesn't include fix to that access. If we backport that commit in future,
 we need to fix its faulting access as well.]

Fixes: c25b2ae13603 ("bpf: Replace PTR_TO_XXX_OR_NULL with PTR_TO_XXX | PTR_MAYBE_NULL")
Signed-off-by: Kumar Kartikeya Dwivedi &lt;memxor@gmail.com&gt;
Signed-off-by: Hao Luo &lt;haoluo@google.com&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Link: https://lore.kernel.org/bpf/20220216201943.624869-1-memxor@gmail.com
Cc: stable@vger.kernel.org # v5.15+
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>bpf: Add MEM_RDONLY for helper args that are pointers to rdonly mem.</title>
<updated>2022-05-01T15:22:26Z</updated>
<author>
<name>Hao Luo</name>
<email>haoluo@google.com</email>
</author>
<published>2022-04-28T23:57:49Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=2a77c58726aba893129a369ed3d2be004dda41cd'/>
<id>urn:sha1:2a77c58726aba893129a369ed3d2be004dda41cd</id>
<content type='text'>
commit 216e3cd2f28dbbf1fe86848e0e29e6693b9f0a20 upstream.

Some helper functions may modify its arguments, for example,
bpf_d_path, bpf_get_stack etc. Previously, their argument types
were marked as ARG_PTR_TO_MEM, which is compatible with read-only
mem types, such as PTR_TO_RDONLY_BUF. Therefore it's legitimate,
but technically incorrect, to modify a read-only memory by passing
it into one of such helper functions.

This patch tags the bpf_args compatible with immutable memory with
MEM_RDONLY flag. The arguments that don't have this flag will be
only compatible with mutable memory types, preventing the helper
from modifying a read-only memory. The bpf_args that have
MEM_RDONLY are compatible with both mutable memory and immutable
memory.

Signed-off-by: Hao Luo &lt;haoluo@google.com&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Link: https://lore.kernel.org/bpf/20211217003152.48334-9-haoluo@google.com
Cc: stable@vger.kernel.org # 5.15.x
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>bpf: Make per_cpu_ptr return rdonly PTR_TO_MEM.</title>
<updated>2022-05-01T15:22:25Z</updated>
<author>
<name>Hao Luo</name>
<email>haoluo@google.com</email>
</author>
<published>2022-04-28T23:57:48Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=15166bb3000fc8b5faa8fa606eb25d300e6892ef'/>
<id>urn:sha1:15166bb3000fc8b5faa8fa606eb25d300e6892ef</id>
<content type='text'>
commit 34d3a78c681e8e7844b43d1a2f4671a04249c821 upstream.

Tag the return type of {per, this}_cpu_ptr with RDONLY_MEM. The
returned value of this pair of helpers is kernel object, which
can not be updated by bpf programs. Previously these two helpers
return PTR_OT_MEM for kernel objects of scalar type, which allows
one to directly modify the memory. Now with RDONLY_MEM tagging,
the verifier will reject programs that write into RDONLY_MEM.

Fixes: 63d9b80dcf2c ("bpf: Introducte bpf_this_cpu_ptr()")
Fixes: eaa6bcb71ef6 ("bpf: Introduce bpf_per_cpu_ptr()")
Fixes: 4976b718c355 ("bpf: Introduce pseudo_btf_id")
Signed-off-by: Hao Luo &lt;haoluo@google.com&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Link: https://lore.kernel.org/bpf/20211217003152.48334-8-haoluo@google.com
Cc: stable@vger.kernel.org # 5.15.x
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>bpf: Convert PTR_TO_MEM_OR_NULL to composable types.</title>
<updated>2022-05-01T15:22:25Z</updated>
<author>
<name>Hao Luo</name>
<email>haoluo@google.com</email>
</author>
<published>2022-04-28T23:57:47Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=b710f73704d61069b2f05358309290551e5a8732'/>
<id>urn:sha1:b710f73704d61069b2f05358309290551e5a8732</id>
<content type='text'>
commit cf9f2f8d62eca810afbd1ee6cc0800202b000e57 upstream.

Remove PTR_TO_MEM_OR_NULL and replace it with PTR_TO_MEM combined with
flag PTR_MAYBE_NULL.

Signed-off-by: Hao Luo &lt;haoluo@google.com&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Link: https://lore.kernel.org/bpf/20211217003152.48334-7-haoluo@google.com
Cc: stable@vger.kernel.org # 5.15.x
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>bpf: Introduce MEM_RDONLY flag</title>
<updated>2022-05-01T15:22:24Z</updated>
<author>
<name>Hao Luo</name>
<email>haoluo@google.com</email>
</author>
<published>2022-04-28T23:57:46Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=b453361384c2db1c703dacb806d5fd36aec4ceca'/>
<id>urn:sha1:b453361384c2db1c703dacb806d5fd36aec4ceca</id>
<content type='text'>
commit 20b2aff4bc15bda809f994761d5719827d66c0b4 upstream.

This patch introduce a flag MEM_RDONLY to tag a reg value
pointing to read-only memory. It makes the following changes:

1. PTR_TO_RDWR_BUF -&gt; PTR_TO_BUF
2. PTR_TO_RDONLY_BUF -&gt; PTR_TO_BUF | MEM_RDONLY

Signed-off-by: Hao Luo &lt;haoluo@google.com&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Link: https://lore.kernel.org/bpf/20211217003152.48334-6-haoluo@google.com
Cc: stable@vger.kernel.org # 5.15.x
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>bpf: Replace PTR_TO_XXX_OR_NULL with PTR_TO_XXX | PTR_MAYBE_NULL</title>
<updated>2022-05-01T15:22:24Z</updated>
<author>
<name>Hao Luo</name>
<email>haoluo@google.com</email>
</author>
<published>2022-04-28T23:57:45Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=8d38cde47a7e17b646401fa92d916503caa5375e'/>
<id>urn:sha1:8d38cde47a7e17b646401fa92d916503caa5375e</id>
<content type='text'>
commit c25b2ae136039ffa820c26138ed4a5e5f3ab3841 upstream.

We have introduced a new type to make bpf_reg composable, by
allocating bits in the type to represent flags.

One of the flags is PTR_MAYBE_NULL which indicates a pointer
may be NULL. This patch switches the qualified reg_types to
use this flag. The reg_types changed in this patch include:

1. PTR_TO_MAP_VALUE_OR_NULL
2. PTR_TO_SOCKET_OR_NULL
3. PTR_TO_SOCK_COMMON_OR_NULL
4. PTR_TO_TCP_SOCK_OR_NULL
5. PTR_TO_BTF_ID_OR_NULL
6. PTR_TO_MEM_OR_NULL
7. PTR_TO_RDONLY_BUF_OR_NULL
8. PTR_TO_RDWR_BUF_OR_NULL

[haoluo: backport notes
 There was a reg_type_may_be_null() in adjust_ptr_min_max_vals() in
 5.15.x, but didn't exist in the upstream commit. This backport
 converted that reg_type_may_be_null() to type_may_be_null() as well.]

Signed-off-by: Hao Luo &lt;haoluo@google.com&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Link: https://lore.kernel.org/r/20211217003152.48334-5-haoluo@google.com
Cc: stable@vger.kernel.org # 5.15.x
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>bpf: Replace RET_XXX_OR_NULL with RET_XXX | PTR_MAYBE_NULL</title>
<updated>2022-05-01T15:22:23Z</updated>
<author>
<name>Hao Luo</name>
<email>haoluo@google.com</email>
</author>
<published>2022-04-28T23:57:44Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=3c141c82b95807473d77079936769e04a84e4ca3'/>
<id>urn:sha1:3c141c82b95807473d77079936769e04a84e4ca3</id>
<content type='text'>
commit 3c4807322660d4290ac9062c034aed6b87243861 upstream.

We have introduced a new type to make bpf_ret composable, by
reserving high bits to represent flags.

One of the flag is PTR_MAYBE_NULL, which indicates a pointer
may be NULL. When applying this flag to ret_types, it means
the returned value could be a NULL pointer. This patch
switches the qualified arg_types to use this flag.
The ret_types changed in this patch include:

1. RET_PTR_TO_MAP_VALUE_OR_NULL
2. RET_PTR_TO_SOCKET_OR_NULL
3. RET_PTR_TO_TCP_SOCK_OR_NULL
4. RET_PTR_TO_SOCK_COMMON_OR_NULL
5. RET_PTR_TO_ALLOC_MEM_OR_NULL
6. RET_PTR_TO_MEM_OR_BTF_ID_OR_NULL
7. RET_PTR_TO_BTF_ID_OR_NULL

This patch doesn't eliminate the use of these names, instead
it makes them aliases to 'RET_PTR_TO_XXX | PTR_MAYBE_NULL'.

Signed-off-by: Hao Luo &lt;haoluo@google.com&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Link: https://lore.kernel.org/bpf/20211217003152.48334-4-haoluo@google.com
Cc: stable@vger.kernel.org # 5.15.x
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>bpf: Replace ARG_XXX_OR_NULL with ARG_XXX | PTR_MAYBE_NULL</title>
<updated>2022-05-01T15:22:23Z</updated>
<author>
<name>Hao Luo</name>
<email>haoluo@google.com</email>
</author>
<published>2022-04-28T23:57:43Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=d58a396fa6c98bde64772c1db715dfca32610597'/>
<id>urn:sha1:d58a396fa6c98bde64772c1db715dfca32610597</id>
<content type='text'>
commit 48946bd6a5d695c50b34546864b79c1f910a33c1 upstream.

We have introduced a new type to make bpf_arg composable, by
reserving high bits of bpf_arg to represent flags of a type.

One of the flags is PTR_MAYBE_NULL which indicates a pointer
may be NULL. When applying this flag to an arg_type, it means
the arg can take NULL pointer. This patch switches the
qualified arg_types to use this flag. The arg_types changed
in this patch include:

1. ARG_PTR_TO_MAP_VALUE_OR_NULL
2. ARG_PTR_TO_MEM_OR_NULL
3. ARG_PTR_TO_CTX_OR_NULL
4. ARG_PTR_TO_SOCKET_OR_NULL
5. ARG_PTR_TO_ALLOC_MEM_OR_NULL
6. ARG_PTR_TO_STACK_OR_NULL

This patch does not eliminate the use of these arg_types, instead
it makes them an alias to the 'ARG_XXX | PTR_MAYBE_NULL'.

Signed-off-by: Hao Luo &lt;haoluo@google.com&gt;
Signed-off-by: Alexei Starovoitov &lt;ast@kernel.org&gt;
Link: https://lore.kernel.org/bpf/20211217003152.48334-3-haoluo@google.com
Cc: stable@vger.kernel.org # 5.15.x
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>perf/core: Fix perf_mmap fail when CONFIG_PERF_USE_VMALLOC enabled</title>
<updated>2022-04-27T12:38:58Z</updated>
<author>
<name>Zhipeng Xie</name>
<email>xiezhipeng1@huawei.com</email>
</author>
<published>2022-02-09T14:54:17Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=56637084e8a551e7896d846f1e96415681973cbd'/>
<id>urn:sha1:56637084e8a551e7896d846f1e96415681973cbd</id>
<content type='text'>
[ Upstream commit 60490e7966659b26d74bf1fa4aa8693d9a94ca88 ]

This problem can be reproduced with CONFIG_PERF_USE_VMALLOC enabled on
both x86_64 and aarch64 arch when using sysdig -B(using ebpf)[1].
sysdig -B works fine after rebuilding the kernel with
CONFIG_PERF_USE_VMALLOC disabled.

I tracked it down to the if condition event-&gt;rb-&gt;nr_pages != nr_pages
in perf_mmap is true when CONFIG_PERF_USE_VMALLOC is enabled where
event-&gt;rb-&gt;nr_pages = 1 and nr_pages = 2048 resulting perf_mmap to
return -EINVAL. This is because when CONFIG_PERF_USE_VMALLOC is
enabled, rb-&gt;nr_pages is always equal to 1.

Arch with CONFIG_PERF_USE_VMALLOC enabled by default:
	arc/arm/csky/mips/sh/sparc/xtensa

Arch with CONFIG_PERF_USE_VMALLOC disabled by default:
	x86_64/aarch64/...

Fix this problem by using data_page_nr()

[1] https://github.com/draios/sysdig

Fixes: 906010b2134e ("perf_event: Provide vmalloc() based mmap() backing")
Signed-off-by: Zhipeng Xie &lt;xiezhipeng1@huawei.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Link: https://lkml.kernel.org/r/20220209145417.6495-1-xiezhipeng1@huawei.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>sched/pelt: Fix attach_entity_load_avg() corner case</title>
<updated>2022-04-27T12:38:58Z</updated>
<author>
<name>kuyo chang</name>
<email>kuyo.chang@mediatek.com</email>
</author>
<published>2022-04-14T09:02:20Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=b1b929468229d286b6cd7b09673ef2556d5332bb'/>
<id>urn:sha1:b1b929468229d286b6cd7b09673ef2556d5332bb</id>
<content type='text'>
[ Upstream commit 40f5aa4c5eaebfeaca4566217cb9c468e28ed682 ]

The warning in cfs_rq_is_decayed() triggered:

    SCHED_WARN_ON(cfs_rq-&gt;avg.load_avg ||
		  cfs_rq-&gt;avg.util_avg ||
		  cfs_rq-&gt;avg.runnable_avg)

There exists a corner case in attach_entity_load_avg() which will
cause load_sum to be zero while load_avg will not be.

Consider se_weight is 88761 as per the sched_prio_to_weight[] table.
Further assume the get_pelt_divider() is 47742, this gives:
se-&gt;avg.load_avg is 1.

However, calculating load_sum:

  se-&gt;avg.load_sum = div_u64(se-&gt;avg.load_avg * se-&gt;avg.load_sum, se_weight(se));
  se-&gt;avg.load_sum = 1*47742/88761 = 0.

Then enqueue_load_avg() adds this to the cfs_rq totals:

  cfs_rq-&gt;avg.load_avg += se-&gt;avg.load_avg;
  cfs_rq-&gt;avg.load_sum += se_weight(se) * se-&gt;avg.load_sum;

Resulting in load_avg being 1 with load_sum is 0, which will trigger
the WARN.

Fixes: f207934fb79d ("sched/fair: Align PELT windows between cfs_rq and its se")
Signed-off-by: kuyo chang &lt;kuyo.chang@mediatek.com&gt;
[peterz: massage changelog]
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Reviewed-by: Vincent Guittot &lt;vincent.guittot@linaro.org&gt;
Tested-by: Dietmar Eggemann &lt;dietmar.eggemann@arm.com&gt;
Link: https://lkml.kernel.org/r/20220414090229.342-1-kuyo.chang@mediatek.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
</feed>
