diff options
| author | Clemens Ladisch <clemens@ladisch.de> | 2010-10-15 12:06:18 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-03-21 12:43:11 -0700 |
| commit | 9d55dc791385be8da4013a166f82db745c48e3dd (patch) | |
| tree | fcf33589ca2f7feeb3d61df76fd0b6a74d1348a7 | |
| parent | b259026c5eb96fae5c3c3884a7da7fd13886267f (diff) | |
ALSA: rawmidi: fix oops (use after free) when unloading a driver module
commit aa73aec6c385e2c797ac25cc7ccf0318031de7c8 upstream.
When a driver module is unloaded and the last still open file is a raw
MIDI device, the card and its devices will be actually freed in the
snd_card_file_remove() call when that file is closed. Afterwards, rmidi
and rmidi->card point into freed memory, so the module pointer is likely
to be garbage.
(This was introduced by commit 9a1b64caac82aa02cb74587ffc798e6f42c6170a.)
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Reported-by: Krzysztof Foltman <wdev@foltman.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
| -rw-r--r-- | sound/core/rawmidi.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/sound/core/rawmidi.c b/sound/core/rawmidi.c index 0f5a194695d..5fac1a3158d 100644 --- a/sound/core/rawmidi.c +++ b/sound/core/rawmidi.c @@ -531,13 +531,15 @@ static int snd_rawmidi_release(struct inode *inode, struct file *file) { struct snd_rawmidi_file *rfile; struct snd_rawmidi *rmidi; + struct module *module; rfile = file->private_data; rmidi = rfile->rmidi; rawmidi_release_priv(rfile); kfree(rfile); + module = rmidi->card->module; snd_card_file_remove(rmidi->card, file); - module_put(rmidi->card->module); + module_put(module); return 0; } |