From 18ddb25c7a58404641de2f6aa68220bd509e376c Mon Sep 17 00:00:00 2001 From: Andreas Rheinhardt Date: Wed, 6 Oct 2021 17:21:04 +0200 Subject: [PATCH] avfilter/asrc_flite: Fix use-after-frees When an flite filter instance is uninitialized and the refcount of the corresponding voice_entry reaches zero, the voice is unregistered, yet the voice_entry's pointer to the voice is not reset. (Whereas some other pointers are needlessly reset.) Because of this a new flite filter instance will believe said voice to already be registered, leading to use-after-frees. Fix this by resetting the right pointer instead of the wrong ones. Reviewed-by: Paul B Mahol Signed-off-by: Andreas Rheinhardt --- libavfilter/asrc_flite.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/libavfilter/asrc_flite.c b/libavfilter/asrc_flite.c index 0789dd6ff3..bd2ae774de 100644 --- a/libavfilter/asrc_flite.c +++ b/libavfilter/asrc_flite.c @@ -197,10 +197,10 @@ static av_cold void uninit(AVFilterContext *ctx) FliteContext *flite = ctx->priv; if (flite->voice_entry) { - if (!--flite->voice_entry->usage_count) + if (!--flite->voice_entry->usage_count) { flite->voice_entry->unregister_fn(flite->voice); - flite->voice = NULL; - flite->voice_entry = NULL; + flite->voice_entry->voice = NULL; + } } delete_wave(flite->wave); flite->wave = NULL;