kernel/linux.git/sound/drivers, branch v6.18.33

ALSA: aloop: Fix peer runtime UAF during format-change stop

2026-05-07T04:12:02+00:00

commit e5c33cdc6f402eab8abd36ecf436b22c9d3a8aff upstream. loopback_check_format() may stop the capture side when playback starts with parameters that no longer match a running capture stream. Commit 826af7fa62e3 ("ALSA: aloop: Fix racy access at PCM trigger") moved the peer lookup under cable->lock, but the actual snd_pcm_stop() still runs after dropping that lock. A concurrent close can clear the capture entry from cable->streams[] and detach or free its runtime while the playback trigger path still holds a stale peer substream pointer. Keep a per-cable count of in-flight peer stops before dropping cable->lock, and make free_cable() wait for those stops before detaching the runtime. This preserves the existing behavior while making the peer runtime lifetime explicit. Reported-by: syzbot+8fa95c41eafbc9d2ff6f@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=8fa95c41eafbc9d2ff6f Fixes: 597603d615d2 ("ALSA: introduce the snd-aloop module for the PCM loopback") Cc: stable@vger.kernel.org Suggested-by: Takashi Iwai Signed-off-by: Cássio Gabriel Link: https://patch.msgid.link/20260424-alsa-aloop-peer-stop-uaf-v2-1-94e68101db8a@gmail.com Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman

ALSA: pcmtest: Fix resource leaks in module init error paths

2026-05-07T04:11:43+00:00

commit d5d5f80416a3a749906c04d56575e2290792654b upstream. pcmtest allocates its pattern buffers and creates its debugfs tree before registering the platform device and driver, but mod_init() does not release those resources when a later init step fails. As a result, a debugfs directory creation failure leaks the pattern buffers, while platform_device_register() and platform_driver_register() failures leave both the pattern buffers and the debugfs tree behind. The recent fix for failed device registration only dropped the embedded device reference. Add the missing cleanup for the debugfs tree and pattern buffers in the remaining module init error paths. Fixes: 315a3d57c64c ("ALSA: Implement the new Virtual PCM Test Driver") Cc: stable@vger.kernel.org Signed-off-by: Cássio Gabriel Link: https://patch.msgid.link/20260421-alsa-pcmtest-init-unwind-v1-1-03fe0c423dbb@gmail.com Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman

ALSA: pcmtest: fix reference leak on failed device registration

2026-05-07T04:11:43+00:00

commit 4ff036f95238f02c87e5d7c0a9d93748582a8950 upstream. When platform_device_register() fails in mod_init(), the embedded struct device in pcmtst_pdev has already been initialized by device_initialize(), but the failure path returns the error without dropping the device reference for the current platform device: mod_init() -> platform_device_register(&pcmtst_pdev) -> device_initialize(&pcmtst_pdev.dev) -> setup_pdev_dma_masks(&pcmtst_pdev) -> platform_device_add(&pcmtst_pdev) This leads to a reference leak when platform_device_register() fails. Fix this by calling platform_device_put() before returning the error. The issue was identified by a static analysis tool I developed and confirmed by manual review. Fixes: 315a3d57c64c5 ("ALSA: Implement the new Virtual PCM Test Driver") Cc: stable@vger.kernel.org Signed-off-by: Guangshuo Li Link: https://patch.msgid.link/20260415193138.3861297-1-lgs201920130244@gmail.com Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman

ALSA: aloop: Fix racy access at PCM trigger

2026-02-11T12:41:41+00:00

commit 826af7fa62e347464b1b4e0ba2fe19a92438084f upstream. The PCM trigger callback of aloop driver tries to check the PCM state and stop the stream of the tied substream in the corresponding cable. Since both check and stop operations are performed outside the cable lock, this may result in UAF when a program attempts to trigger frequently while opening/closing the tied stream, as spotted by fuzzers. For addressing the UAF, this patch changes two things: - It covers the most of code in loopback_check_format() with cable->lock spinlock, and add the proper NULL checks. This avoids already some racy accesses. - In addition, now we try to check the state of the capture PCM stream that may be stopped in this function, which was the major pain point leading to UAF. Reported-by: syzbot+5f8f3acdee1ec7a7ef7b@syzkaller.appspotmail.com Closes: https://lore.kernel.org/69783ba1.050a0220.c9109.0011.GAE@google.com Cc: Link: https://patch.msgid.link/20260203141003.116584-1-tiwai@suse.de Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman

ALSA: serial-generic: remove shared static buffer

2025-09-15T10:33:53+00:00

If multiple instances of this driver are instantiated and try to send concurrently then the single static buffer snd_serial_generic_tx_work() will cause corruption in the data output. Move the buffer into the per-instance driver data to avoid this. Signed-off-by: John Keeping Signed-off-by: Takashi Iwai

ALSA: serial-u16550: Use guard() for spin locks

2025-09-01T11:53:35+00:00

Clean up the code using guard() for spin locks. Merely code refactoring, and no behavior change. Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20250829150026.6379-14-tiwai@suse.de

ALSA: portman2x4: Use guard() for spin locks

2025-09-01T11:53:35+00:00

Clean up the code using guard() for spin locks. Merely code refactoring, and no behavior change. Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20250829150026.6379-13-tiwai@suse.de

ALSA: mts64: Use guard() for spin locks

2025-09-01T11:53:35+00:00

Clean up the code using guard() for spin locks. Merely code refactoring, and no behavior change. Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20250829150026.6379-12-tiwai@suse.de

ALSA: mtpav: Use guard() for spin locks

2025-09-01T11:53:35+00:00

Clean up the code using guard() for spin locks. Merely code refactoring, and no behavior change. Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20250829150026.6379-11-tiwai@suse.de

ALSA: mpu401: Use guard() for spin locks

2025-09-01T11:53:34+00:00

Clean up the code using guard() for spin locks. Merely code refactoring, and no behavior change. Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20250829150026.6379-10-tiwai@suse.de