From a45e3d6b13e97506b616980c0f122c3389bcefa4 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Thu, 24 Mar 2011 09:50:15 +0100 Subject: [PATCH] ALSA: Fix yet another race in disconnection This patch fixes a race between snd_card_file_remove() and snd_card_disconnect(). When the card is added to shutdown_files list in snd_card_disconnect(), but it's freed in snd_card_file_remove() at the same time, the shutdown_files list gets corrupted. The list member must be freed in snd_card_file_remove() as well. Reported-and-tested-by: Russ Dill Cc: Signed-off-by: Takashi Iwai --- sound/core/init.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/sound/core/init.c b/sound/core/init.c index 3e65da21a08c..a0080aa45ae9 100644 --- a/sound/core/init.c +++ b/sound/core/init.c @@ -848,6 +848,7 @@ int snd_card_file_add(struct snd_card *card, struct file *file) return -ENOMEM; mfile->file = file; mfile->disconnected_f_op = NULL; + INIT_LIST_HEAD(&mfile->shutdown_list); spin_lock(&card->files_lock); if (card->shutdown) { spin_unlock(&card->files_lock); @@ -883,6 +884,9 @@ int snd_card_file_remove(struct snd_card *card, struct file *file) list_for_each_entry(mfile, &card->files_list, list) { if (mfile->file == file) { list_del(&mfile->list); + spin_lock(&shutdown_lock); + list_del(&mfile->shutdown_list); + spin_unlock(&shutdown_lock); if (mfile->disconnected_f_op) fops_put(mfile->disconnected_f_op); found = mfile;