[PATCH v1 1/3] lib subcmd: Fix memory leak in uniq

From: Ian Rogers
Date: Thu Dec 07 2023 - 19:05:30 EST


uniq will write one command name over another causing the overwritten
string to be leaked. Fix by doing a pass that removes duplicates and a
second that removes the holes.

Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
tools/lib/subcmd/help.c | 18 ++++++++++++++----
1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/tools/lib/subcmd/help.c b/tools/lib/subcmd/help.c
index adfbae27dc36..8561b0f01a24 100644
--- a/tools/lib/subcmd/help.c
+++ b/tools/lib/subcmd/help.c
@@ -52,11 +52,21 @@ void uniq(struct cmdnames *cmds)
if (!cmds->cnt)
return;

- for (i = j = 1; i < cmds->cnt; i++)
- if (strcmp(cmds->names[i]->name, cmds->names[i-1]->name))
- cmds->names[j++] = cmds->names[i];
-
+ for (i = 1; i < cmds->cnt; i++) {
+ if (!strcmp(cmds->names[i]->name, cmds->names[i-1]->name))
+ zfree(&cmds->names[i - 1]);
+ }
+ for (i = 0, j = 0; i < cmds->cnt; i++) {
+ if (cmds->names[i]) {
+ if (i == j)
+ j++;
+ else
+ cmds->names[j++] = cmds->names[i];
+ }
+ }
cmds->cnt = j;
+ while (j < i)
+ cmds->names[j++] = NULL;
}

void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
--
2.43.0.472.g3155946c3a-goog