From e0cd3e38de139be4929fe8b18d85da585580420b Mon Sep 17 00:00:00 2001 From: Florin Malita Date: Mon, 16 Oct 2006 14:43:43 +0200 Subject: [PATCH] [PATCH] ALSA: Dereference after free in snd_hwdep_release() snd_card_file_remove() may free hw->card so we can't dereference hw->card->module after that. Coverity ID 1420. This bug actually causes an Oops at usb-disconnection, especially with CONFIG_PREEMPT. From: Florin Malita Signed-off-by: Florin Malita Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman Signed-off-by: Chris Wright --- sound/core/hwdep.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/sound/core/hwdep.c b/sound/core/hwdep.c index 8bd0dcc93eba9..a562f96f30102 100644 --- a/sound/core/hwdep.c +++ b/sound/core/hwdep.c @@ -158,6 +158,7 @@ static int snd_hwdep_release(struct inode *inode, struct file * file) { int err = -ENXIO; struct snd_hwdep *hw = file->private_data; + struct module *mod = hw->card->module; mutex_lock(&hw->open_mutex); if (hw->ops.release) { err = hw->ops.release(hw, file); @@ -167,7 +168,7 @@ static int snd_hwdep_release(struct inode *inode, struct file * file) hw->used--; snd_card_file_remove(hw->card, file); mutex_unlock(&hw->open_mutex); - module_put(hw->card->module); + module_put(mod); return err; } -- 2.47.2