Commit d4145960 authored by James Clark's avatar James Clark Committed by Arnaldo Carvalho de Melo
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perf dso: Fix /proc/kcore access on 32 bit systems 



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: default avatarDenis Nikitin <denik@chromium.org>
Signed-off-by: default avatarJames Clark <james.clark@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/20211021112700.112499-1-james.clark@arm.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent e277ac28

tools/perf/util/dso.h

+1 −1
Original line number Diff line number Diff line
@@ -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;