[PATCH] perf tools: Fix /proc/kcore access on 32 bit systems

From: James Clark
Date: Thu Oct 21 2021 - 07:27:35 EST


Because _LARGEFILE64_SOURCE is set in perf, file offset sizes can be
64 bits. If a workflow needs to open /proc/kcore on a 32 bit system
(for example to decode Arm ETM kernel trace) then the size value will be
wrapped to 32 bits in the function file_size() at this line:

dso->data.file_size = st.st_size;

Setting the file_size member to be u64 fixes the issue and allows
/proc/kcore to be opened.

Reported-by: Denis Nikitin <denik@xxxxxxxxxxxx>
Signed-off-by: James Clark <james.clark@xxxxxxx>
---
tools/perf/util/dso.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h
index 83723ba11dc8..011da3924fc1 100644
--- a/tools/perf/util/dso.h
+++ b/tools/perf/util/dso.h
@@ -193,7 +193,7 @@ struct dso {
int fd;
int status;
u32 status_seen;
- size_t file_size;
+ u64 file_size;
struct list_head open_entry;
u64 debug_frame_offset;
u64 eh_frame_hdr_offset;
--
2.28.0