This is a note to let you know that I've just added the patch titled
libsubcmd: Don't free the usage string
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
libsubcmd-don-t-free-the-usage-string.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit e0802cf78be343991bbf6fb1d471490993af3057
Author: Aditya Gupta <adityag@xxxxxxxxxxxxx>
Date: Wed Sep 4 11:48:30 2024 +0530
libsubcmd: Don't free the usage string
[ Upstream commit 1a5efc9e13f357abc396dbf445b25d08914c8060 ]
Currently, commands which depend on 'parse_options_subcommand()' don't
show the usage string, and instead show '(null)'
$ ./perf sched
Usage: (null)
-D, --dump-raw-trace dump raw trace in ASCII
-f, --force don't complain, do it
-i, --input <file> input file name
-v, --verbose be more verbose (show symbol address, etc)
'parse_options_subcommand()' is generally expected to initialise the usage
string, with information in the passed 'subcommands[]' array
This behaviour was changed in:
230a7a71f92212e7 ("libsubcmd: Fix parse-options memory leak")
Where the generated usage string is deallocated, and usage[0] string is
reassigned as NULL.
As discussed in [1], free the allocated usage string in the main
function itself, and don't reset usage string to NULL in
parse_options_subcommand
With this change, the behaviour is restored.
$ ./perf sched
Usage: perf sched [<options>] {record|latency|map|replay|script|timehist}
-D, --dump-raw-trace dump raw trace in ASCII
-f, --force don't complain, do it
-i, --input <file> input file name
-v, --verbose be more verbose (show symbol address, etc)
[1]: https://lore.kernel.org/linux-perf-users/htq5vhx6piet4nuq2mmhk7fs2bhfykv52dbppwxmo3s7du2odf@styd27tioc6e/
Fixes: 230a7a71f92212e7 ("libsubcmd: Fix parse-options memory leak")
Suggested-by: Namhyung Kim <namhyung@xxxxxxxxxx>
Signed-off-by: Aditya Gupta <adityag@xxxxxxxxxxxxx>
Acked-by: Namhyung Kim <namhyung@xxxxxxxxxx>
Tested-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Athira Rajeev <atrajeev@xxxxxxxxxxxxxxxxxx>
Cc: Disha Goel <disgoel@xxxxxxxxxxxxxxxxxx>
Cc: Ian Rogers <irogers@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Kajol Jain <kjain@xxxxxxxxxxxxx>
Cc: Madhavan Srinivasan <maddy@xxxxxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240904061836.55873-2-adityag@xxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/tools/lib/subcmd/parse-options.c b/tools/lib/subcmd/parse-options.c
index d943d78b787ed..9fa75943f2ed1 100644
--- a/tools/lib/subcmd/parse-options.c
+++ b/tools/lib/subcmd/parse-options.c
@@ -633,10 +633,11 @@ int parse_options_subcommand(int argc, const char **argv, const struct option *o
const char *const subcommands[], const char *usagestr[], int flags)
{
struct parse_opt_ctx_t ctx;
- char *buf = NULL;
/* build usage string if it's not provided */
if (subcommands && !usagestr[0]) {
+ char *buf = NULL;
+
astrcatf(&buf, "%s %s [<options>] {", subcmd_config.exec_name, argv[0]);
for (int i = 0; subcommands[i]; i++) {
@@ -678,10 +679,7 @@ int parse_options_subcommand(int argc, const char **argv, const struct option *o
astrcatf(&error_buf, "unknown switch `%c'", *ctx.opt);
usage_with_options(usagestr, options);
}
- if (buf) {
- usagestr[0] = NULL;
- free(buf);
- }
+
return parse_options_end(&ctx);
}
diff --git a/tools/perf/builtin-kmem.c b/tools/perf/builtin-kmem.c
index 9714327fd0ead..cf623c1490d95 100644
--- a/tools/perf/builtin-kmem.c
+++ b/tools/perf/builtin-kmem.c
@@ -2058,6 +2058,8 @@ int cmd_kmem(int argc, const char **argv)
out_delete:
perf_session__delete(session);
+ /* free usage string allocated by parse_options_subcommand */
+ free((void *)kmem_usage[0]);
return ret;
}
diff --git a/tools/perf/builtin-kvm.c b/tools/perf/builtin-kvm.c
index 71165036e4cac..988bef73bd095 100644
--- a/tools/perf/builtin-kvm.c
+++ b/tools/perf/builtin-kvm.c
@@ -2187,5 +2187,8 @@ int cmd_kvm(int argc, const char **argv)
else
usage_with_options(kvm_usage, kvm_options);
+ /* free usage string allocated by parse_options_subcommand */
+ free((void *)kvm_usage[0]);
+
return 0;
}
diff --git a/tools/perf/builtin-kwork.c b/tools/perf/builtin-kwork.c
index de2fbb7c56c32..be210be42c77b 100644
--- a/tools/perf/builtin-kwork.c
+++ b/tools/perf/builtin-kwork.c
@@ -1853,5 +1853,8 @@ int cmd_kwork(int argc, const char **argv)
} else
usage_with_options(kwork_usage, kwork_options);
+ /* free usage string allocated by parse_options_subcommand */
+ free((void *)kwork_usage[0]);
+
return 0;
}
diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c
index 0b4b4445c5207..fcb32c58bee7e 100644
--- a/tools/perf/builtin-lock.c
+++ b/tools/perf/builtin-lock.c
@@ -2622,6 +2622,9 @@ int cmd_lock(int argc, const char **argv)
usage_with_options(lock_usage, lock_options);
}
+ /* free usage string allocated by parse_options_subcommand */
+ free((void *)lock_usage[0]);
+
zfree(&lockhash_table);
return rc;
}
diff --git a/tools/perf/builtin-mem.c b/tools/perf/builtin-mem.c
index 865f321d729b6..286105be91cec 100644
--- a/tools/perf/builtin-mem.c
+++ b/tools/perf/builtin-mem.c
@@ -518,5 +518,8 @@ int cmd_mem(int argc, const char **argv)
else
usage_with_options(mem_usage, mem_options);
+ /* free usage string allocated by parse_options_subcommand */
+ free((void *)mem_usage[0]);
+
return 0;
}
diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c
index 994b9dcb2385a..ac9d94dbbeefa 100644
--- a/tools/perf/builtin-sched.c
+++ b/tools/perf/builtin-sched.c
@@ -3737,5 +3737,8 @@ int cmd_sched(int argc, const char **argv)
usage_with_options(sched_usage, sched_options);
}
+ /* free usage string allocated by parse_options_subcommand */
+ free((void *)sched_usage[0]);
+
return 0;
}
