| From a45e3d6b13e97506b616980c0f122c3389bcefa4 Mon Sep 17 00:00:00 2001 |
| From: Takashi Iwai <tiwai@suse.de> |
| Date: Thu, 24 Mar 2011 09:50:15 +0100 |
| Subject: ALSA: Fix yet another race in disconnection |
| |
| From: Takashi Iwai <tiwai@suse.de> |
| |
| commit a45e3d6b13e97506b616980c0f122c3389bcefa4 upstream. |
| |
| 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 <russ.dill@gmail.com> |
| Signed-off-by: Takashi Iwai <tiwai@suse.de> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> |
| |
| --- |
| sound/core/init.c | 4 ++++ |
| 1 file changed, 4 insertions(+) |
| |
| --- a/sound/core/init.c |
| +++ b/sound/core/init.c |
| @@ -848,6 +848,7 @@ int snd_card_file_add(struct snd_card *c |
| 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 |
| 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; |
