From f30fbe3901da0f57a6b40102ae1c3ab3a9ff6744 Mon Sep 17 00:00:00 2001 From: Stephen Warren Date: Thu, 2 Jun 2011 16:45:13 -0600 Subject: [PATCH] alsaucm: Don't double-free empty lists When snd_use_case_get_list (and hence also snd_use_case_card_list) returns an empty list, alsaucm still attempts to free it. This ends up double- freeing the returned list, or worse, freeing an invalid pointer, depending on how snd_use_case_get_list gets implemented. Fix alsaucm to return early on empty lists to avoid this. Signed-off-by: Stephen Warren Signed-off-by: Jaroslav Kysela --- alsaucm/usecase.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/alsaucm/usecase.c b/alsaucm/usecase.c index f24e63e..1c94680 100644 --- a/alsaucm/usecase.c +++ b/alsaucm/usecase.c @@ -226,8 +226,10 @@ static int do_one(struct context *context, struct cmd *cmd, char **argv) snd_strerror(err)); return err; } - if (err == 0) + if (err == 0) { printf(" list is empty\n"); + return 0; + } for (i = 0; i < err / 2; i++) { printf(" %i: %s\n", i, list[i*2]); if (list[i*2+1]) @@ -256,8 +258,10 @@ static int do_one(struct context *context, struct cmd *cmd, char **argv) snd_strerror(err)); return err; } - if (err == 0) + if (err == 0) { printf(" list is empty\n"); + return 0; + } for (i = 0; i < err / entries; i++) { printf(" %i: %s\n", i, list[i*entries]); for (j = 0; j < entries - 1; j++)