bpf: Clear the probe_addr for uprobe

[ Upstream commit 5125e757e62f6c1d5478db4c2b61a744060ddf3f ]

To avoid returning uninitialized or random values when querying the file
descriptor (fd) and accessing probe_addr, it is necessary to clear the
variable prior to its use.

Fixes: 41bdc4b40ed6 ("bpf: introduce bpf subcommand BPF_TASK_FD_QUERY")
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20230709025630.3735-6-laoar.shao@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
index ff137179e0c30ab58428f6f5beb78372ec47a920..9c91c3531d83025dc6f76cb78bb49ea259614b1c 100644 (file)
--- a/include/linux/trace_events.h
+++ b/include/linux/trace_events.h
@@ -846,7 +846,8 @@ extern int  perf_uprobe_init(struct perf_event *event,
 extern void perf_uprobe_destroy(struct perf_event *event);
 extern int bpf_get_uprobe_info(const struct perf_event *event,
                               u32 *fd_type, const char **filename,
-                              u64 *probe_offset, bool perf_type_tracepoint);
+                              u64 *probe_offset, u64 *probe_addr,
+                              bool perf_type_tracepoint);
 #endif
 extern int  ftrace_profile_set_filter(struct perf_event *event, int event_id,
                                     char *filter_str);

diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 6352a41380e53d8ae87b1c47aa51466710fbdaae..85a36b19c2b80d4943f09e9ea1cac778c503bd48 100644 (file)
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -1996,7 +1996,7 @@ int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id,
 #ifdef CONFIG_UPROBE_EVENTS
                if (flags & TRACE_EVENT_FL_UPROBE)
                        err = bpf_get_uprobe_info(event, fd_type, buf,
-                                                 probe_offset,
+                                                 probe_offset, probe_addr,
                                                  event->attr.type == PERF_TYPE_TRACEPOINT);
 #endif
        }

diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index debc651015489308f5872d2c986187192ed18e41..720b46b34ab9414d768f744439616acaeeacd12e 100644 (file)
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -1423,7 +1423,7 @@ static void uretprobe_perf_func(struct trace_uprobe *tu, unsigned long func,
 
 int bpf_get_uprobe_info(const struct perf_event *event, u32 *fd_type,
                        const char **filename, u64 *probe_offset,
-                       bool perf_type_tracepoint)
+                       u64 *probe_addr, bool perf_type_tracepoint)
 {
        const char *pevent = trace_event_name(event->tp_event);
        const char *group = event->tp_event->class->system;
@@ -1440,6 +1440,7 @@ int bpf_get_uprobe_info(const struct perf_event *event, u32 *fd_type,
                                    : BPF_FD_TYPE_UPROBE;
        *filename = tu->filename;
        *probe_offset = tu->offset;
+       *probe_addr = 0;
        return 0;
 }
 #endif /* CONFIG_PERF_EVENTS */