linux.git/tools/lib, branch v5.7.15

tools lib traceevent: Fix memory leak in process_dynamic_array_len

2020-08-11T13:35:38+00:00

[ Upstream commit e24c6447ccb7b1a01f9bf0aec94939e6450c0b4d ]

I compiled with AddressSanitizer and I had these memory leaks while I
was using the tep_parse_format function:

    Direct leak of 28 byte(s) in 4 object(s) allocated from:
        #0 0x7fb07db49ffe in __interceptor_realloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10dffe)
        #1 0x7fb07a724228 in extend_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:985
        #2 0x7fb07a724c21 in __read_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1140
        #3 0x7fb07a724f78 in read_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1206
        #4 0x7fb07a725191 in __read_expect_type /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1291
        #5 0x7fb07a7251df in read_expect_type /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1299
        #6 0x7fb07a72e6c8 in process_dynamic_array_len /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:2849
        #7 0x7fb07a7304b8 in process_function /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3161
        #8 0x7fb07a730900 in process_arg_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3207
        #9 0x7fb07a727c0b in process_arg /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1786
        #10 0x7fb07a731080 in event_read_print_args /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3285
        #11 0x7fb07a731722 in event_read_print /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3369
        #12 0x7fb07a740054 in __tep_parse_format /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6335
        #13 0x7fb07a74047a in __parse_event /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6389
        #14 0x7fb07a740536 in tep_parse_format /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6431
        #15 0x7fb07a785acf in parse_event ../../../src/fs-src/fs.c:251
        #16 0x7fb07a785ccd in parse_systems ../../../src/fs-src/fs.c:284
        #17 0x7fb07a786fb3 in read_metadata ../../../src/fs-src/fs.c:593
        #18 0x7fb07a78760e in ftrace_fs_source_init ../../../src/fs-src/fs.c:727
        #19 0x7fb07d90c19c in add_component_with_init_method_data ../../../../src/lib/graph/graph.c:1048
        #20 0x7fb07d90c87b in add_source_component_with_initialize_method_data ../../../../src/lib/graph/graph.c:1127
        #21 0x7fb07d90c92a in bt_graph_add_source_component ../../../../src/lib/graph/graph.c:1152
        #22 0x55db11aa632e in cmd_run_ctx_create_components_from_config_components ../../../src/cli/babeltrace2.c:2252
        #23 0x55db11aa6fda in cmd_run_ctx_create_components ../../../src/cli/babeltrace2.c:2347
        #24 0x55db11aa780c in cmd_run ../../../src/cli/babeltrace2.c:2461
        #25 0x55db11aa8a7d in main ../../../src/cli/babeltrace2.c:2673
        #26 0x7fb07d5460b2 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x270b2)

The token variable in the process_dynamic_array_len function is
allocated in the read_expect_type function, but is not freed before
calling the read_token function.

Free the token variable before calling read_token in order to plug the
leak.

Signed-off-by: Philippe Duplessis-Guindon 
Reviewed-by: Steven Rostedt (VMware) 
Link: https://lore.kernel.org/linux-trace-devel/20200730150236.5392-1-pduplessis@efficios.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

libtraceevent: Fix build with binutils 2.35

2020-08-05T07:58:38+00:00

commit 39efdd94e314336f4acbac4c07e0f37bdc3bef71 upstream.

In binutils 2.35, 'nm -D' changed to show symbol versions along with
symbol names, with the usual @@ separator.  When generating
libtraceevent-dynamic-list we need just the names, so strip off the
version suffix if present.

Signed-off-by: Ben Hutchings 
Tested-by: Salvatore Bonaccorso 
Reviewed-by: Steven Rostedt 
Cc: linux-trace-devel@vger.kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Greg Kroah-Hartman

tools lib traceevent: Handle attribute((user)) in field names

2020-07-09T07:39:29+00:00

[ Upstream commit 74621d929d944529a5e2878a84f48bfa6fb69a66 ]

Commit c61f13eaa1ee1 ("gcc-plugins: Add structleak for more stack
initialization") added "__attribute__((user))" to the user when
stackleak detector is enabled. This now appears in the field format of
system call trace events for system calls that have user buffers. The
"__attribute__((user))" breaks the parsing in libtraceevent. That needs
to be handled.

Signed-off-by: Steven Rostedt (VMware) 
Cc: Andrew Morton 
Cc: Jaewon Kim 
Cc: Jiri Olsa 
Cc: Kees Kook 
Cc: Namhyung Kim 
Cc: Vlastimil Babka 
Cc: linux-mm@kvack.org
Cc: linux-trace-devel@vger.kernel.org
Link: http://lore.kernel.org/lkml/20200324200956.663647256@goodmis.org
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

tools lib traceevent: Add append() function helper for appending strings

2020-07-09T07:39:29+00:00

[ Upstream commit 27d4d336f2872193e90ee5450559e1699fae0f6d ]

There's several locations that open code realloc and strcat() to append
text to strings. Add an append() function that takes a delimiter and a
string to append to another string.

Signed-off-by: Steven Rostedt (VMware) 
Cc: Andrew Morton 
Cc: Jaewon Lim 
Cc: Jiri Olsa 
Cc: Kees Kook 
Cc: linux-mm@kvack.org
Cc: linux-trace-devel@vger.kernel.org
Cc: Namhyung Kim 
Cc: Vlastimil Babka 
Link: http://lore.kernel.org/lkml/20200324200956.515118403@goodmis.org
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

libbpf: Support pre-initializing .bss global variables

2020-06-24T15:49:11+00:00

[ Upstream commit caf62492f479585296e9d636c798d5ac256b7b04 ]

Remove invalid assumption in libbpf that .bss map doesn't have to be updated
in kernel. With addition of skeleton and memory-mapped initialization image,
.bss doesn't have to be all zeroes when BPF map is created, because user-code
might have initialized those variables from user-space.

Fixes: eba9c5f498a1 ("libbpf: Refactor global data map initialization")
Signed-off-by: Andrii Nakryiko 
Signed-off-by: Alexei Starovoitov 
Link: https://lore.kernel.org/bpf/20200612194504.557844-1-andriin@fb.com
Signed-off-by: Sasha Levin

libbpf: Handle GCC noreturn-turned-volatile quirk

2020-06-24T15:49:09+00:00

[ Upstream commit 32022fd97ed34f6812802bf1288db27c313576f4 ]

Handle a GCC quirk of emitting extra volatile modifier in DWARF (and
subsequently preserved in BTF by pahole) for function pointers marked as
__attribute__((noreturn)). This was the way to mark such functions before GCC
2.5 added noreturn attribute. Drop such func_proto modifiers, similarly to how
it's done for array (also to handle GCC quirk/bug).

Such volatile attribute is emitted by GCC only, so existing selftests can't
express such test. Simple repro is like this (compiled with GCC + BTF
generated by pahole):

  struct my_struct {
      void __attribute__((noreturn)) (*fn)(int);
  };
  struct my_struct a;

Without this fix, output will be:

struct my_struct {
    voidvolatile  (*fn)(int);
};

With the fix:

struct my_struct {
    void (*fn)(int);
};

Fixes: 351131b51c7a ("libbpf: add btf_dump API for BTF-to-C conversion")
Reported-by: Jean-Philippe Brucker 
Signed-off-by: Andrii Nakryiko 
Signed-off-by: Daniel Borkmann 
Tested-by: Jean-Philippe Brucker 
Link: https://lore.kernel.org/bpf/20200610052335.2862559-1-andriin@fb.com
Signed-off-by: Sasha Levin

libbpf: Fix perf_buffer__free() API for sparse allocs

2020-06-22T07:32:53+00:00

[ Upstream commit 601b05ca6edb0422bf6ce313fbfd55ec7bbbc0fd ]

In case the cpu_bufs are sparsely allocated they are not all
free'ed. These changes will fix this.

Fixes: fb84b8224655 ("libbpf: add perf buffer API")
Signed-off-by: Eelco Chaudron 
Signed-off-by: Daniel Borkmann 
Acked-by: Andrii Nakryiko 
Link: https://lore.kernel.org/bpf/159056888305.330763.9684536967379110349.stgit@ebuild
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Sasha Levin

libbpf: Fix huge memory leak in libbpf_find_vmlinux_btf_id()

2020-06-22T07:32:34+00:00

[ Upstream commit 3521ffa2ee9a48c3236c93f54ae11c074490ebce ]

BTF object wasn't freed.

Fixes: a6ed02cac690 ("libbpf: Load btf_vmlinux only once per object.")
Signed-off-by: Andrii Nakryiko 
Signed-off-by: Alexei Starovoitov 
Cc: KP Singh 
Link: https://lore.kernel.org/bpf/20200429012111.277390-9-andriin@fb.com
Signed-off-by: Sasha Levin

libbpf: Refactor map creation logic and fix cleanup leak

2020-06-22T07:32:33+00:00

[ Upstream commit 2d39d7c56f115148b05d1d8c6b8698a5730c8b53 ]

Factor out map creation and destruction logic to simplify code and especially
error handling. Also fix map FD leak in case of partially successful map
creation during bpf_object load operation.

Fixes: 57a00f41644f ("libbpf: Add auto-pinning of maps when loading BPF objects")
Signed-off-by: Andrii Nakryiko 
Signed-off-by: Alexei Starovoitov 
Acked-by: Toke Høiland-Jørgensen 
Link: https://lore.kernel.org/bpf/20200429002739.48006-3-andriin@fb.com
Signed-off-by: Sasha Levin

tools api fs: Make xxx__mountpoint() more scalable

2020-06-22T07:32:29+00:00

[ Upstream commit c6fddb28bad26e5472cb7acf7b04cd5126f1a4ab ]

The xxx_mountpoint() interface provided by fs.c finds mount points for
common pseudo filesystems. The first time xxx_mountpoint() is invoked,
it scans the mount table (/proc/mounts) looking for a match. If found,
it is cached. The price to scan /proc/mounts is paid once if the mount
is found.

When the mount point is not found, subsequent calls to xxx_mountpoint()
scan /proc/mounts over and over again.  There is no caching.

This causes a scaling issue in perf record with hugeltbfs__mountpoint().
The function is called for each process found in
synthesize__mmap_events().  If the machine has thousands of processes
and if the /proc/mounts has many entries this could cause major overhead
in perf record. We have observed multi-second slowdowns on some
configurations.

As an example on a laptop:

Before:

  $ sudo umount /dev/hugepages
  $ strace -e trace=openat -o /tmp/tt perf record -a ls
  $ fgrep mounts /tmp/tt
  285

After:

  $ sudo umount /dev/hugepages
  $ strace -e trace=openat -o /tmp/tt perf record -a ls
  $ fgrep mounts /tmp/tt
  1

One could argue that the non-caching in case the moint point is not
found is intentional. That way subsequent calls may discover a moint
point if the sysadmin mounts the filesystem. But the same argument could
be made against caching the mount point. It could be unmounted causing
errors.  It all depends on the intent of the interface. This patch
assumes it is expected to scan /proc/mounts once. The patch documents
the caching behavior in the fs.h header file.

An alternative would be to just fix perf record. But it would solve the
problem with hugetlbs__mountpoint() but there could be similar issues
(possibly down the line) with other xxx_mountpoint() calls in perf or
other tools.

Signed-off-by: Stephane Eranian 
Reviewed-by: Ian Rogers 
Acked-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Andrey Zhizhikin 
Cc: Kan Liang 
Cc: Kefeng Wang 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Petr Mladek 
Cc: Thomas Gleixner 
Link: http://lore.kernel.org/lkml/20200402154357.107873-3-irogers@google.com
Signed-off-by: Ian Rogers 
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin