From 6810158d526e483868e519befff407b91e76b3db Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Wed, 14 Mar 2018 10:34:11 -0300 Subject: [PATCH] perf annotate: Use asprintf when formatting objdump command line We were using a local buffer with an arbitrary size, that would have to get increased to avoid truncation as warned by gcc 8: util/annotate.c: In function 'symbol__disassemble': util/annotate.c:1488:4: error: '%s' directive output may be truncated writing up to 4095 bytes into a region of size between 3966 and 8086 [-Werror=format-truncation=] "%s %s%s --start-address=0x%016" PRIx64 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ util/annotate.c:1498:20: symfs_filename, symfs_filename); ~~~~~~~~~~~~~~ util/annotate.c:1490:50: note: format string is defined here " -l -d %s %s -C \"%s\" 2>/dev/null|grep -v \"%s:\"|expand", ^~ In file included from /usr/include/stdio.h:861, from util/color.h:5, from util/sort.h:8, from util/annotate.c:14: /usr/include/bits/stdio2.h:67:10: note: '__builtin___snprintf_chk' output 116 or more bytes (assuming 8331) into a destination of size 8192 return __builtin___snprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ __bos (__s), __fmt, __va_arg_pack ()); ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ So switch to asprintf, that will make sure enough space is available. Cc: Adrian Hunter Cc: David Ahern Cc: Jin Yao Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: https://lkml.kernel.org/n/tip-qagoy2dmbjpc9gdnaj0r3mml@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/annotate.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-) diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c index bc3302da702b..ddad87f34a68 100644 --- a/tools/perf/util/annotate.c +++ b/tools/perf/util/annotate.c @@ -1427,7 +1427,7 @@ static int symbol__disassemble(struct symbol *sym, struct annotate_args *args) { struct map *map = args->map; struct dso *dso = map->dso; - char command[PATH_MAX * 2]; + char *command; FILE *file; char symfs_filename[PATH_MAX]; struct kcore_extract kce; @@ -1468,7 +1468,7 @@ static int symbol__disassemble(struct symbol *sym, struct annotate_args *args) strcpy(symfs_filename, tmp); } - snprintf(command, sizeof(command), + err = asprintf(&command, "%s %s%s --start-address=0x%016" PRIx64 " --stop-address=0x%016" PRIx64 " -l -d %s %s -C \"%s\" 2>/dev/null|grep -v \"%s:\"|expand", @@ -1481,12 +1481,17 @@ static int symbol__disassemble(struct symbol *sym, struct annotate_args *args) symbol_conf.annotate_src ? "-S" : "", symfs_filename, symfs_filename); + if (err < 0) { + pr_err("Failure allocating memory for the command to run\n"); + goto out_remove_tmp; + } + pr_debug("Executing: %s\n", command); err = -1; if (pipe(stdout_fd) < 0) { pr_err("Failure creating the pipe to run %s\n", command); - goto out_remove_tmp; + goto out_free_command; } pid = fork(); @@ -1513,7 +1518,7 @@ static int symbol__disassemble(struct symbol *sym, struct annotate_args *args) * If we were using debug info should retry with * original binary. */ - goto out_remove_tmp; + goto out_free_command; } nline = 0; @@ -1541,6 +1546,8 @@ static int symbol__disassemble(struct symbol *sym, struct annotate_args *args) fclose(file); err = 0; +out_free_command: + free(command); out_remove_tmp: close(stdout_fd[0]); @@ -1554,7 +1561,7 @@ out: out_close_stdout: close(stdout_fd[1]); - goto out_remove_tmp; + goto out_free_command; } static void calc_percent(struct sym_hist *hist,