diff options
| author | Casey Chen <cachen@purestorage.com> | 2024-07-23 00:15:48 +0300 |
|---|---|---|
| committer | Namhyung Kim <namhyung@kernel.org> | 2024-07-26 21:12:16 +0300 |
| commit | 4c17736689ccfc44ec7dcc472577f25c34cf8724 (patch) | |
| tree | a16fbc5d5ab91ea8e88787c913047ce0aea2c7a3 | |
| parent | 92717bc077892d1ce60fee07aee3a33f33909b85 (diff) | |
| download | linux-4c17736689ccfc44ec7dcc472577f25c34cf8724.tar.xz | |
perf tool: fix dereferencing NULL al->maps
With 0dd5041c9a0e ("perf addr_location: Add init/exit/copy functions"),
when cpumode is 3 (macro PERF_RECORD_MISC_HYPERVISOR),
thread__find_map() could return with al->maps being NULL.
The path below could add a callchain_cursor_node with NULL ms.maps.
add_callchain_ip()
thread__find_symbol(.., &al)
thread__find_map(.., &al) // al->maps becomes NULL
ms.maps = maps__get(al.maps)
callchain_cursor_append(..., &ms, ...)
node->ms.maps = maps__get(ms->maps)
Then the path below would dereference NULL maps and get segfault.
fill_callchain_info()
maps__machine(node->ms.maps);
Fix it by checking if maps is NULL in fill_callchain_info().
Fixes: 0dd5041c9a0e ("perf addr_location: Add init/exit/copy functions")
Signed-off-by: Casey Chen <cachen@purestorage.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Reviewed-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: yzhong@purestorage.com
Link: https://lore.kernel.org/r/20240722211548.61455-1-cachen@purestorage.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
| -rw-r--r-- | tools/perf/util/callchain.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c index 1730b852a947..6d075648d2cc 100644 --- a/tools/perf/util/callchain.c +++ b/tools/perf/util/callchain.c @@ -1141,7 +1141,7 @@ int hist_entry__append_callchain(struct hist_entry *he, struct perf_sample *samp int fill_callchain_info(struct addr_location *al, struct callchain_cursor_node *node, bool hide_unresolved) { - struct machine *machine = maps__machine(node->ms.maps); + struct machine *machine = node->ms.maps ? maps__machine(node->ms.maps) : NULL; maps__put(al->maps); al->maps = maps__get(node->ms.maps); |