From: Song Liu <[email protected]> Added missing machine->id_hdr_size to event->header.size. Also fixed size of PERF_RECORD_KSYMBOL by removing extra bytes for name.
Committer notes: We need to malloc that extra machine->id_hdr_size at the start of perf_event__synthesize_bpf_events() and also need to cast the event to (void *) otherwise we segfault, fix it. Reported-by: Arnaldo Carvalho de Melo <[email protected]> Suggested-by: Jiri Olsa <[email protected]> Signed-off-by: Song Liu <[email protected]> Acked-by: Jiri Olsa <[email protected]> Tested-by: Arnaldo Carvalho de Melo <[email protected]> Cc: Alexei Starovoitov <[email protected]> Cc: Daniel Borkmann <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: [email protected] Fixes: 7b612e291a5a ("perf tools: Synthesize PERF_RECORD_* for loaded BPF programs") Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> --- tools/perf/util/bpf-event.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/tools/perf/util/bpf-event.c b/tools/perf/util/bpf-event.c index 01e1dc1bb7fb..796ef793f4ce 100644 --- a/tools/perf/util/bpf-event.c +++ b/tools/perf/util/bpf-event.c @@ -7,6 +7,7 @@ #include "bpf-event.h" #include "debug.h" #include "symbol.h" +#include "machine.h" #define ptr_to_u64(ptr) ((__u64)(unsigned long)(ptr)) @@ -149,7 +150,7 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_tool *tool, *ksymbol_event = (struct ksymbol_event){ .header = { .type = PERF_RECORD_KSYMBOL, - .size = sizeof(struct ksymbol_event), + .size = offsetof(struct ksymbol_event, name), }, .addr = prog_addrs[i], .len = prog_lens[i], @@ -178,6 +179,9 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_tool *tool, ksymbol_event->header.size += PERF_ALIGN(name_len + 1, sizeof(u64)); + + memset((void *)event + event->header.size, 0, machine->id_hdr_size); + event->header.size += machine->id_hdr_size; err = perf_tool__process_synth_event(tool, event, machine, process); } @@ -194,6 +198,8 @@ static int perf_event__synthesize_one_bpf_prog(struct perf_tool *tool, .id = info.id, }; memcpy(bpf_event->tag, prog_tags[i], BPF_TAG_SIZE); + memset((void *)event + event->header.size, 0, machine->id_hdr_size); + event->header.size += machine->id_hdr_size; err = perf_tool__process_synth_event(tool, event, machine, process); } @@ -217,7 +223,7 @@ int perf_event__synthesize_bpf_events(struct perf_tool *tool, int err; int fd; - event = malloc(sizeof(event->bpf_event) + KSYM_NAME_LEN); + event = malloc(sizeof(event->bpf_event) + KSYM_NAME_LEN + machine->id_hdr_size); if (!event) return -1; while (true) { -- 2.20.1

