kernel.git/sound/core/oss, branch linux-3.2.y

ALSA: pcm: potential uninitialized return values

2018-05-31T23:30:25Z

commit 5607dddbfca774fb38bffadcb077fe03aa4ac5c6 upstream. Smatch complains that "tmp" can be uninitialized if we do a zero size write. Fixes: 02a5d6925cd3 ("ALSA: pcm: Avoid potential races between OSS ioctls and read/write") Signed-off-by: Dan Carpenter Signed-off-by: Takashi Iwai Signed-off-by: Ben Hutchings

ALSA: pcm: Allow aborting mutex lock at OSS read/write loops

2018-03-03T15:50:57Z

commit 900498a34a3ac9c611e9b425094c8106bdd7dc1c upstream. PCM OSS read/write loops keep taking the mutex lock for the whole read/write, and this might take very long when the exceptionally high amount of data is given. Also, since it invokes with mutex_lock(), the concurrent read/write becomes unbreakable. This patch tries to address these issues by replacing mutex_lock() with mutex_lock_interruptible(), and also splits / re-takes the lock at each read/write period chunk, so that it can switch the context more finely if requested. Signed-off-by: Takashi Iwai Signed-off-by: Ben Hutchings

ALSA: pcm: Abort properly at pending signal in OSS read/write loops

2018-03-03T15:50:56Z

commit 29159a4ed7044c52e3e2cf1a9fb55cec4745c60b upstream. The loops for read and write in PCM OSS emulation have no proper check of pending signals, and they keep processing even after user tries to break. This results in a very long delay, often seen as RCU stall when a huge unprocessed bytes remain queued. The bug could be easily triggered by syzkaller. As a simple workaround, this patch adds the proper check of pending signals and aborts the loop appropriately. Reported-by: syzbot+993cb4cfcbbff3947c21@syzkaller.appspotmail.com Signed-off-by: Takashi Iwai Signed-off-by: Ben Hutchings

ALSA: pcm: Add missing error checks in OSS emulation plugin builder

2018-03-03T15:50:54Z

commit 6708913750344a900f2e73bfe4a4d6dbbce4fe8d upstream. In the OSS emulation plugin builder where the frame size is parsed in the plugin chain, some places miss the possible errors returned from the plugin src_ or dst_frames callback. This patch papers over such places. Signed-off-by: Takashi Iwai Signed-off-by: Ben Hutchings

ALSA: pcm: Remove incorrect snd_BUG_ON() usages

2018-03-03T15:50:53Z

commit fe08f34d066f4404934a509b6806db1a4f700c86 upstream. syzkaller triggered kernel warnings through PCM OSS emulation at closing a stream: WARNING: CPU: 0 PID: 3502 at sound/core/pcm_lib.c:1635 snd_pcm_hw_param_first+0x289/0x690 sound/core/pcm_lib.c:1635 Call Trace: .... snd_pcm_hw_param_near.constprop.27+0x78d/0x9a0 sound/core/oss/pcm_oss.c:457 snd_pcm_oss_change_params+0x17d3/0x3720 sound/core/oss/pcm_oss.c:969 snd_pcm_oss_make_ready+0xaa/0x130 sound/core/oss/pcm_oss.c:1128 snd_pcm_oss_sync+0x257/0x830 sound/core/oss/pcm_oss.c:1638 snd_pcm_oss_release+0x20b/0x280 sound/core/oss/pcm_oss.c:2431 __fput+0x327/0x7e0 fs/file_table.c:210 .... This happens while it tries to open and set up the aloop device concurrently. The warning above (invoked from snd_BUG_ON() macro) is to detect the unexpected logical error where snd_pcm_hw_refine() call shouldn't fail. The theory is true for the case where the hw_params config rules are static. But for an aloop device, the hw_params rule condition does vary dynamically depending on the connected target; when another device is opened and changes the parameters, the device connected in another side is also affected, and it caused the error from snd_pcm_hw_refine(). That is, the simplest "solution" for this is to remove the incorrect assumption of static rules, and treat such an error as a normal error path. As there are a couple of other places using snd_BUG_ON() incorrectly, this patch removes these spurious snd_BUG_ON() calls. Reported-by: syzbot+6f11c7e2a1b91d466432@syzkaller.appspotmail.com Signed-off-by: Takashi Iwai Signed-off-by: Ben Hutchings

ALSA: pcm: Fix potential deadlock in OSS emulation

2016-02-27T14:28:45Z

commit b248371628aad599a48540962f6b85a21a8a0c3f upstream. There are potential deadlocks in PCM OSS emulation code while accessing read/write and mmap concurrently. This comes from the infamous mmap_sem usage in copy_from/to_user(). Namely, snd_pcm_oss_write() -> &runtime->oss.params_lock -> copy_to_user() -> &mm->mmap_sem mmap() -> &mm->mmap_sem -> snd_pcm_oss_mmap() -> &runtime->oss.params_lock Since we can't avoid taking params_lock from mmap code path, use trylock variant and aborts with -EAGAIN as a workaround of this AB/BA deadlock. BugLink: http://lkml.kernel.org/r/CACT4Y+bVrBKDG0G2_AcUgUQa+X91VKTeS4v+wN7BSHwHtqn3kQ@mail.gmail.com Reported-by: Dmitry Vyukov Signed-off-by: Takashi Iwai Signed-off-by: Ben Hutchings

ALSA: Fix card refcount unbalance

2012-11-16T16:47:11Z

commit 8bb4d9ce08b0a92ca174e41d92c180328f86173f upstream. There are uncovered cases whether the card refcount introduced by the commit a0830dbd isn't properly increased or decreased: - OSS PCM and mixer success paths - When lookup function gets NULL This patch fixes these places. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=50251 Signed-off-by: Takashi Iwai Signed-off-by: Ben Hutchings

ALSA: Avoid endless sleep after disconnect

2012-11-16T16:46:50Z

commit 0914f7961babbf28aaa2f19b453951fb4841c03f upstream. When disconnect callback is called, each component should wake up sleepers and check card->shutdown flag for avoiding the endless sleep blocking the proper resource release. Signed-off-by: Takashi Iwai Signed-off-by: Ben Hutchings

ALSA: Add a reference counter to card instance

2012-11-16T16:46:50Z

commit a0830dbd4e42b38aefdf3fb61ba5019a1a99ea85 upstream. For more strict protection for wild disconnections, a refcount is introduced to the card instance, and let it up/down when an object is referred via snd_lookup_*() in the open ops. The free-after-last-close check is also changed to check this refcount instead of the empty list, too. Reported-by: Matthieu CASTET Signed-off-by: Takashi Iwai Signed-off-by: Ben Hutchings

sound: Add module.h to the previously silent sound users

2011-10-31T23:31:21Z

Lots of sound drivers were getting module.h via the implicit presence of it in but we are going to clean that up. So fix up those users now. Signed-off-by: Paul Gortmaker