[tip:perf/core] perf symbols: Don't try to synthesize plt without dynstr

[tip-bot for Cody P Schafer]

Commit-ID:  52f9ddba516214a59fdd8eb155b2583ab314dc31
Gitweb:     http://git.kernel.org/tip/52f9ddba516214a59fdd8eb155b2583ab314dc31
Author:     Cody P Schafer <cody@xxxxxxxxxxxxxxxxxx>
AuthorDate: Fri, 10 Aug 2012 15:22:51 -0700
Committer:  Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitDate: Mon, 13 Aug 2012 12:56:45 -0300

perf symbols: Don't try to synthesize plt without dynstr

If .dynsym exists but .dynstr is empty (NO_BITS or size==0), a segfault
occurs.  Avoid this by checking that .dynstr is not empty.

Signed-off-by: Cody P Schafer <cody@xxxxxxxxxxxxxxxxxx>
Cc: David Hansen <dave@xxxxxxxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Matt Hellsley <matthltc@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Sukadev Bhattiprolu <sukadev@xxxxxxxxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/1344637382-22789-6-git-send-email-cody@xxxxxxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
 tools/perf/util/symbol-elf.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c
index e037609..a2e994e 100644
--- a/tools/perf/util/symbol-elf.c
+++ b/tools/perf/util/symbol-elf.c
@@ -232,6 +232,9 @@ int dso__synthesize_plt_symbols(struct dso *dso, char *name, struct map *map,
 	if (symstrs == NULL)
 		goto out_elf_end;
 
+	if (symstrs->d_size == 0)
+		goto out_elf_end;
+
 	nr_rel_entries = shdr_rel_plt.sh_size / shdr_rel_plt.sh_entsize;
 	plt_offset = shdr_plt.sh_offset;
 
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/