kernel/linux.git/sound/usb/endpoint.c, branch linux-7.1.y

ALSA: usb-audio: Evaluate packsize caps at the right place

2026-04-10T14:34:06+00:00

We introduced the upper bound checks of the packet sizes by the ep->maxframesize for avoiding the URB submission errors. However, the check was applied at an incorrect place in the function snd_usb_endpoint_set_params() where ep->maxframesize isn't defined yet; the value is defined at a bit later position. So this ended up with a failure at the first run while the second run works. For fixing it, move the check at the correct place, right after the calculation of ep->maxframesize in the same function. Fixes: 7fe8dec3f628 ("ALSA: usb-audio: Cap the packet size pre-calculations") Link: https://bugzilla.kernel.org/show_bug.cgi?id=221292 Cc: Link: https://patch.msgid.link/20260410143220.1676344-1-tiwai@suse.de Signed-off-by: Takashi Iwai

ALSA: usb-audio: Use inclusive terms

2026-02-25T09:17:28+00:00

Replace the remaining with inclusive terms; it's only this function name we overlooked at the previous conversion. Fixes: 53837b4ac2bd ("ALSA: usb-audio: Replace slave/master terms") Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20260225085233.316306-5-tiwai@suse.de Signed-off-by: Takashi Iwai

ALSA: usb-audio: Check max frame size for implicit feedback mode, too

2026-02-25T09:17:28+00:00

When the packet sizes are taken from the capture stream in the implicit feedback mode, the sizes might be larger than the upper boundary defined by the descriptor. As already done for other transfer modes, we have to cap the sizes accordingly at sending, otherwise this would lead to an error in USB core at submission of URBs. Link: https://bugzilla.kernel.org/show_bug.cgi?id=221076 Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20260225085233.316306-3-tiwai@suse.de Signed-off-by: Takashi Iwai

ALSA: usb-audio: Cap the packet size pre-calculations

2026-02-25T09:17:27+00:00

We calculate the possible packet sizes beforehand for adaptive and synchronous endpoints, but we didn't take care of the max frame size for those pre-calculated values. When a device or a bus limits the packet size, a high sample rate or a high number of channels may lead to the packet sizes that are larger than the given limit, which results in an error from the USB core at submitting URBs. As a simple workaround, just add the sanity checks of pre-calculated packet sizes to have the upper boundary of ep->maxframesize. Fixes: f0bd62b64016 ("ALSA: usb-audio: Improve frames size computation") Link: https://bugzilla.kernel.org/show_bug.cgi?id=221076 Signed-off-by: Takashi Iwai Link: https://patch.msgid.link/20260225085233.316306-2-tiwai@suse.de Signed-off-by: Takashi Iwai

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

ALSA: usb-audio: Avoid potentially repeated XRUN error messages

2026-02-16T14:13:59+00:00

Some XRUN-related error messages may repeat themselves, because there can be multiple pending packets. Modify notify_xrun() function to return whether it's being stopped or not, and show the error message only once when the XRUN is actually handled. Along with it, fix a typo of word package to packet in the error message. Link: https://patch.msgid.link/20260216141209.1849200-5-tiwai@suse.de Signed-off-by: Takashi Iwai

ALSA: usb-audio: Add sanity check for OOB writes at silencing

2026-02-16T14:13:48+00:00

At silencing the playback URB packets in the implicit fb mode before the actual playback, we blindly assume that the received packets fit with the buffer size. But when the setup in the capture stream differs from the playback stream (e.g. due to the USB core limitation of max packet size), such an inconsistency may lead to OOB writes to the buffer, resulting in a crash. For addressing it, add a sanity check of the transfer buffer size at prepare_silent_urb(), and stop the data copy if the received data overflows. Also, report back the transfer error properly from there, too. Note that this doesn't fix the root cause of the playback error itself, but this merely covers the kernel Oops. Link: https://bugzilla.kernel.org/show_bug.cgi?id=221076 Link: https://patch.msgid.link/20260216141209.1849200-4-tiwai@suse.de Signed-off-by: Takashi Iwai

ALSA: usb-audio: Optimize the copy of packet sizes for implicit fb handling

2026-02-16T14:13:35+00:00

We did manual copies over loop for the packet data update of the implicit feedback, but this can be optimized with a simple memcpy(). Along with it, change the data type of snd_usb_packet_info struct to align with other (from uint32_t to int). No functional changes but only code optimizations. Link: https://patch.msgid.link/20260216141209.1849200-3-tiwai@suse.de Signed-off-by: Takashi Iwai

ALSA: usb-audio: Update the number of packets properly at receiving

2026-02-16T14:13:17+00:00

At receiving the packets from the implicit feedback source, we didn't update ctx->packets field but only the ctx->packet_size[] data. In exceptional cases, this might lead to unexpectedly superfluous data transfer (although this won't happen usually due to the nature of USB isochronous transfer). Fix it to update the field properly. Link: https://patch.msgid.link/20260216141209.1849200-2-tiwai@suse.de Signed-off-by: Takashi Iwai