linux-stable.git/tools, branch v6.1.53

XArray: Do not return sibling entries from xa_load()

2023-09-13T07:43:00+00:00

commit cbc02854331edc6dc22d8b77b6e22e38ebc7dd51 upstream.

It is possible for xa_load() to observe a sibling entry pointing to
another sibling entry.  An example:

Thread A:		Thread B:
			xa_store_range(xa, entry, 188, 191, gfp);
xa_load(xa, 191);
entry = xa_entry(xa, node, 63);
[entry is a sibling of 188]
			xa_store_range(xa, entry, 184, 191, gfp);
if (xa_is_sibling(entry))
offset = xa_to_sibling(entry);
entry = xa_entry(xas->xa, node, offset);
[entry is now a sibling of 184]

It is sufficient to go around this loop until we hit a non-sibling entry.
Sibling entries always point earlier in the node, so we are guaranteed
to terminate this search.

Signed-off-by: Matthew Wilcox (Oracle) 
Fixes: 6b24ca4a1a8d ("mm: Use multi-index entries in the page cache")
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

selftests/bpf: Clean up fmod_ret in bench_rename test script

2023-09-13T07:42:33+00:00

[ Upstream commit 83a89c4b6ae93481d3f618aba6a29d89208d26ed ]

Running the bench_rename test script, the following error occurs:

  # ./benchs/run_bench_rename.sh
  base      :    0.819 ± 0.012M/s
  kprobe    :    0.538 ± 0.009M/s
  kretprobe :    0.503 ± 0.004M/s
  rawtp     :    0.779 ± 0.020M/s
  fentry    :    0.726 ± 0.007M/s
  fexit     :    0.691 ± 0.007M/s
  benchmark 'rename-fmodret' not found

The bench_rename_fmodret has been removed in commit b000def2e052
("selftests: Remove fmod_ret from test_overhead"), thus remove it
from the runners in the test script.

Fixes: b000def2e052 ("selftests: Remove fmod_ret from test_overhead")
Signed-off-by: Yipeng Zou 
Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/20230814030727.3010390-1-zouyipeng@huawei.com
Signed-off-by: Sasha Levin

selftests/bpf: Fix repeat option when kfunc_call verification fails

2023-09-13T07:42:33+00:00

[ Upstream commit 811915db674f8daf19bb4fcb67da9017235ce26d ]

There is no way where topts.repeat can be set to 1 when tc_test fails.
Fix the typo where the break statement slipped by one line.

Fixes: fb66223a244f ("selftests/bpf: add test for accessing ctx from syscall program type")
Signed-off-by: Yipeng Zou 
Signed-off-by: Daniel Borkmann 
Reviewed-by: Li Zetao 
Link: https://lore.kernel.org/bpf/20230814031434.3077944-1-zouyipeng@huawei.com
Signed-off-by: Sasha Levin

selftests/bpf: fix static assert compilation issue for test_cls_*.c

2023-09-13T07:42:32+00:00

[ Upstream commit 416c6d01244ecbf0abfdb898fd091b50ef951b48 ]

commit bdeeed3498c7 ("libbpf: fix offsetof() and container_of() to work with CO-RE")

...was backported to stable trees such as 5.15. The problem is that with older
LLVM/clang (14/15) - which is often used for older kernels - we see compilation
failures in BPF selftests now:

In file included from progs/test_cls_redirect_subprogs.c:2:
progs/test_cls_redirect.c:90:2: error: static assertion expression is not an integral constant expression
        sizeof(flow_ports_t) !=
        ^~~~~~~~~~~~~~~~~~~~~~~
progs/test_cls_redirect.c:91:3: note: cast that performs the conversions of a reinterpret_cast is not allowed in a constant expression
                offsetofend(struct bpf_sock_tuple, ipv4.dport) -
                ^
progs/test_cls_redirect.c:32:3: note: expanded from macro 'offsetofend'
        (offsetof(TYPE, MEMBER) + sizeof((((TYPE *)0)->MEMBER)))
         ^
tools/testing/selftests/bpf/tools/include/bpf/bpf_helpers.h:86:33: note: expanded from macro 'offsetof'
                                 ^
In file included from progs/test_cls_redirect_subprogs.c:2:
progs/test_cls_redirect.c:95:2: error: static assertion expression is not an integral constant expression
        sizeof(flow_ports_t) !=
        ^~~~~~~~~~~~~~~~~~~~~~~
progs/test_cls_redirect.c:96:3: note: cast that performs the conversions of a reinterpret_cast is not allowed in a constant expression
                offsetofend(struct bpf_sock_tuple, ipv6.dport) -
                ^
progs/test_cls_redirect.c:32:3: note: expanded from macro 'offsetofend'
        (offsetof(TYPE, MEMBER) + sizeof((((TYPE *)0)->MEMBER)))
         ^
tools/testing/selftests/bpf/tools/include/bpf/bpf_helpers.h:86:33: note: expanded from macro 'offsetof'
                                 ^
2 errors generated.
make: *** [Makefile:594: tools/testing/selftests/bpf/test_cls_redirect_subprogs.bpf.o] Error 1

The problem is the new offsetof() does not play nice with static asserts.
Given that the context is a static assert (and CO-RE relocation is not
needed at compile time), offsetof() usage can be replaced by restoring
the original offsetof() definition as __builtin_offsetof().

Fixes: bdeeed3498c7 ("libbpf: fix offsetof() and container_of() to work with CO-RE")
Reported-by: Colm Harrington 
Signed-off-by: Alan Maguire 
Tested-by: Yipeng Zou 
Acked-by: Yonghong Song 
Link: https://lore.kernel.org/r/20230802073906.3197480-1-alan.maguire@oracle.com
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Sasha Levin

libbpf: Fix realloc API handling in zero-sized edge cases

2023-09-13T07:42:30+00:00

[ Upstream commit 8a0260dbf6553c969248b6530cafadac46562f47 ]

realloc() and reallocarray() can either return NULL or a special
non-NULL pointer, if their size argument is zero. This requires a bit
more care to handle NULL-as-valid-result situation differently from
NULL-as-error case. This has caused real issues before ([0]), and just
recently bit again in production when performing bpf_program__attach_usdt().

This patch fixes 4 places that do or potentially could suffer from this
mishandling of NULL, including the reported USDT-related one.

There are many other places where realloc()/reallocarray() is used and
NULL is always treated as an error value, but all those have guarantees
that their size is always non-zero, so those spot don't need any extra
handling.

  [0] d08ab82f59d5 ("libbpf: Fix double-free when linker processes empty sections")

Fixes: 999783c8bbda ("libbpf: Wire up spec management and other arch-independent USDT logic")
Fixes: b63b3c490eee ("libbpf: Add bpf_program__set_insns function")
Fixes: 697f104db8a6 ("libbpf: Support custom SEC() handlers")
Fixes: b12688267280 ("libbpf: Change the order of data and text relocations.")
Signed-off-by: Andrii Nakryiko 
Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/20230711024150.1566433-1-andrii@kernel.org
Signed-off-by: Sasha Levin

bpftool: Use a local bpf_perf_event_value to fix accessing its fields

2023-09-13T07:42:30+00:00

[ Upstream commit 658ac06801315b739774a15796ff06913ef5cad5 ]

Fix the following error when building bpftool:

  CLANG   profiler.bpf.o
  CLANG   pid_iter.bpf.o
skeleton/profiler.bpf.c:18:21: error: invalid application of 'sizeof' to an incomplete type 'struct bpf_perf_event_value'
        __uint(value_size, sizeof(struct bpf_perf_event_value));
                           ^     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
tools/bpf/bpftool/bootstrap/libbpf/include/bpf/bpf_helpers.h:13:39: note: expanded from macro '__uint'
tools/bpf/bpftool/bootstrap/libbpf/include/bpf/bpf_helper_defs.h:7:8: note: forward declaration of 'struct bpf_perf_event_value'
struct bpf_perf_event_value;
       ^

struct bpf_perf_event_value is being used in the kernel only when
CONFIG_BPF_EVENTS is enabled, so it misses a BTF entry then.
Define struct bpf_perf_event_value___local with the
`preserve_access_index` attribute inside the pid_iter BPF prog to
allow compiling on any configs. It is a full mirror of a UAPI
structure, so is compatible both with and w/o CO-RE.
bpf_perf_event_read_value() requires a pointer of the original type,
so a cast is needed.

Fixes: 47c09d6a9f67 ("bpftool: Introduce "prog profile" command")
Suggested-by: Andrii Nakryiko 
Signed-off-by: Alexander Lobakin 
Signed-off-by: Quentin Monnet 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20230707095425.168126-5-quentin@isovalent.com
Signed-off-by: Sasha Levin

bpftool: Use a local copy of BPF_LINK_TYPE_PERF_EVENT in pid_iter.bpf.c

2023-09-13T07:42:30+00:00

[ Upstream commit 44ba7b30e84fb40da2295e85a6d209e199fdc977 ]

In order to allow the BPF program in bpftool's pid_iter.bpf.c to compile
correctly on hosts where vmlinux.h does not define
BPF_LINK_TYPE_PERF_EVENT (running kernel versions lower than 5.15, for
example), define and use a local copy of the enum value. This requires
LLVM 12 or newer to build the BPF program.

Fixes: cbdaf71f7e65 ("bpftool: Add bpf_cookie to link output")
Signed-off-by: Quentin Monnet 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20230707095425.168126-4-quentin@isovalent.com
Signed-off-by: Sasha Levin

bpftool: Define a local bpf_perf_link to fix accessing its fields

2023-09-13T07:42:30+00:00

[ Upstream commit 67a43462ee2405c94e985a747bdcb8e3a0d66203 ]

When building bpftool with !CONFIG_PERF_EVENTS:

skeleton/pid_iter.bpf.c:47:14: error: incomplete definition of type 'struct bpf_perf_link'
        perf_link = container_of(link, struct bpf_perf_link, link);
                    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
tools/bpf/bpftool/bootstrap/libbpf/include/bpf/bpf_helpers.h:74:22: note: expanded from macro 'container_of'
                ((type *)(__mptr - offsetof(type, member)));    \
                                   ^~~~~~~~~~~~~~~~~~~~~~
tools/bpf/bpftool/bootstrap/libbpf/include/bpf/bpf_helpers.h:68:60: note: expanded from macro 'offsetof'
 #define offsetof(TYPE, MEMBER)  ((unsigned long)&((TYPE *)0)->MEMBER)
                                                  ~~~~~~~~~~~^
skeleton/pid_iter.bpf.c:44:9: note: forward declaration of 'struct bpf_perf_link'
        struct bpf_perf_link *perf_link;
               ^

&bpf_perf_link is being defined and used only under the ifdef.
Define struct bpf_perf_link___local with the `preserve_access_index`
attribute inside the pid_iter BPF prog to allow compiling on any
configs. CO-RE will substitute it with the real struct bpf_perf_link
accesses later on.
container_of() uses offsetof(), which does the necessary CO-RE
relocation if the field is specified with `preserve_access_index` - as
is the case for struct bpf_perf_link___local.

Fixes: cbdaf71f7e65 ("bpftool: Add bpf_cookie to link output")
Suggested-by: Andrii Nakryiko 
Signed-off-by: Alexander Lobakin 
Signed-off-by: Quentin Monnet 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20230707095425.168126-3-quentin@isovalent.com
Signed-off-by: Sasha Levin

bpftool: use a local copy of perf_event to fix accessing :: Bpf_cookie

2023-09-13T07:42:30+00:00

[ Upstream commit 4cbeeb0dc02f8ac7b975b2ab0080ace53d43d62a ]

When CONFIG_PERF_EVENTS is not set, struct perf_event remains empty.
However, the structure is being used by bpftool indirectly via BTF.
This leads to:

skeleton/pid_iter.bpf.c:49:30: error: no member named 'bpf_cookie' in 'struct perf_event'
        return BPF_CORE_READ(event, bpf_cookie);
               ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~

...

skeleton/pid_iter.bpf.c:49:9: error: returning 'void' from a function with incompatible result type '__u64' (aka 'unsigned long long')
        return BPF_CORE_READ(event, bpf_cookie);
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Tools and samples can't use any CONFIG_ definitions, so the fields
used there should always be present.
Define struct perf_event___local with the `preserve_access_index`
attribute inside the pid_iter BPF prog to allow compiling on any
configs. CO-RE will substitute it with the real struct perf_event
accesses later on.

Fixes: cbdaf71f7e65 ("bpftool: Add bpf_cookie to link output")
Suggested-by: Andrii Nakryiko 
Signed-off-by: Alexander Lobakin 
Signed-off-by: Quentin Monnet 
Signed-off-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/20230707095425.168126-2-quentin@isovalent.com
Signed-off-by: Sasha Levin

selftests/bpf: Fix bpf_nf failure upon test rerun

2023-09-13T07:42:30+00:00

[ Upstream commit 17e8e5d6e09adb4b4f4fb5c89b3ec3fcae2c64a6 ]

Alexei reported:

  After fast forwarding bpf-next today bpf_nf test started to fail when
  run twice:

  $ ./test_progs -t bpf_nf
  #17      bpf_nf:OK
  Summary: 1/10 PASSED, 0 SKIPPED, 0 FAILED

  $ ./test_progs -t bpf_nf
  All error logs:
  test_bpf_nf_ct:PASS:test_bpf_nf__open_and_load 0 nsec
  test_bpf_nf_ct:PASS:iptables-legacy -t raw -A PREROUTING -j CONNMARK
  --set-mark 42/0 0 nsec
  (network_helpers.c:102: errno: Address already in use) Failed to bind socket
  test_bpf_nf_ct:FAIL:start_server unexpected start_server: actual -1 < expected 0
  #17/1    bpf_nf/xdp-ct:FAIL
  test_bpf_nf_ct:PASS:test_bpf_nf__open_and_load 0 nsec
  test_bpf_nf_ct:PASS:iptables-legacy -t raw -A PREROUTING -j CONNMARK
  --set-mark 42/0 0 nsec
  (network_helpers.c:102: errno: Address already in use) Failed to bind socket
  test_bpf_nf_ct:FAIL:start_server unexpected start_server: actual -1 < expected 0
  #17/2    bpf_nf/tc-bpf-ct:FAIL
  #17      bpf_nf:FAIL
  Summary: 0/8 PASSED, 0 SKIPPED, 1 FAILED

I was able to locally reproduce as well. Rearrange the connection teardown
so that the client closes its connection first so that we don't need to
linger in TCP time-wait.

Fixes: e81fbd4c1ba7 ("selftests/bpf: Add existing connection bpf_*_ct_lookup() test")
Reported-by: Alexei Starovoitov 
Signed-off-by: Daniel Borkmann 
Link: https://lore.kernel.org/bpf/CAADnVQ+0dnDq_v_vH1EfkacbfGnHANaon7zsw10pMb-D9FS0Pw@mail.gmail.com
Link: https://lore.kernel.org/bpf/20230626131942.5100-1-daniel@iogearbox.net
Signed-off-by: Sasha Levin