ALSA: ua101: reject mismatched capture/playback packet sizes
Summary
| CVE | CVE-2026-98741 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-10-18 16:17:27 UTC |
| Updated | 2026-10-30 13:21:22 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: ALSA: ua101: reject mismatched capture/playback packet sizes detect_usb_format() cross-checks bSubframeSize, bBitResolution and tSamFreq between the capture and playback interfaces, but never relates the two endpoints' wMaxPacketSize and bNrChannels. Each playback URB gets a buffer of ua->playback.max_packet_bytes, while the number of bytes written into it is derived from the capture stream: capture_urb_complete() computes frames from the received capture packet and capture.frame_bytes, and start_usb_playback() and playback_work() multiply that by playback.frame_bytes. A device declaring a large capture wMaxPacketSize with few capture channels and a small playback wMaxPacketSize with many playback channels therefore memset()s and memcpy()s past the end of the playback buffer, in open() of the PCM node the driver registers during probe. usb_submit_urb() rejects the over-long iso_frame_desc[0].length with -EMSGSIZE, but only after the write. Reject such descriptors at probe time. Genuine UA-101/UA-1000 hardware declares proportional packet sizes and is unaffected. BUG: KASAN: slab-out-of-bounds in start_usb_playback (sound/usb/misc/ua101.c:586) Write of size 2048 at addr ffff8881098f3c00 by task exploit/5021 Call Trace: __asan_memset (mm/kasan/shadow.c:84) start_usb_playback (sound/usb/misc/ua101.c:586) playback_pcm_open (sound/usb/misc/ua101.c:679) snd_pcm_open_substream (sound/core/pcm_native.c:2829) snd_pcm_open (sound/core/pcm_native.c:2865 sound/core/pcm_native.c:2932) snd_pcm_playback_open (sound/core/pcm_native.c:2891) snd_open (sound/core/sound.c:166) chrdev_open (fs/char_dev.c:411) do_dentry_open (fs/open.c:996) vfs_open (fs/open.c:1101) path_openat (fs/namei.c:4837 fs/namei.c:5000) do_file_open (fs/namei.c:5029) do_sys_openat2 (fs/open.c:1417) __x64_sys_openat (fs/open.c:1423 fs/open.c:1439 fs/open.c:1434) do_syscall_64 (arch/x86/entry/syscall_64.c:61 arch/x86/entry/syscall_64.c:84) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121) The buggy address belongs to the object at ffff8881098f3c00 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 0 bytes inside of allocated 168-byte region [ffff8881098f3c00, ffff8881098f3ca8) |
Risk And Classification
EPSS: 0.001760000 probability, percentile 0.071510000 (date 2026-11-01)
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected 63978ab3e3e963db28093b53bb4598f2702e1ad7 b54976c81a6b8cae311b75be1a4cda444689bca0 git | Not specified |
| CNA | Linux | Linux | affected 63978ab3e3e963db28093b53bb4598f2702e1ad7 a2d326b3f6d470ea4bfde00245794e0dc6dbbc3d git | Not specified |
| CNA | Linux | Linux | affected 63978ab3e3e963db28093b53bb4598f2702e1ad7 0a6a5eecc92c13f936d8d90975116d6bbdf4f876 git | Not specified |
| CNA | Linux | Linux | affected 63978ab3e3e963db28093b53bb4598f2702e1ad7 ada5ded765f059a6e3036e69ca350449442af0fc git | Not specified |
| CNA | Linux | Linux | affected 63978ab3e3e963db28093b53bb4598f2702e1ad7 fd3a7bf0d988b0878a1957df150edb35f81db87e git | Not specified |
| CNA | Linux | Linux | affected 63978ab3e3e963db28093b53bb4598f2702e1ad7 eb0c7fda59cf650076f8ed5b949a6c8441aa3606 git | Not specified |
| CNA | Linux | Linux | affected 63978ab3e3e963db28093b53bb4598f2702e1ad7 4294fe57048594a9e158b61c967bb7f943cda477 git | Not specified |
| CNA | Linux | Linux | affected 63978ab3e3e963db28093b53bb4598f2702e1ad7 86f86e6fdedc33c5b8d38b9208b350f8accf57ee git | Not specified |
| CNA | Linux | Linux | affected 2.6.34 | Not specified |
| CNA | Linux | Linux | unaffected 2.6.34 semver | Not specified |
| CNA | Linux | Linux | unaffected 5.10.273 5.10.* semver | Not specified |
| CNA | Linux | Linux | unaffected 5.15.224 5.15.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.191 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.160 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.113 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.56 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.2.10 7.2.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.3 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/4294fe57048594a9e158b61c967bb7f943cda477 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/86f86e6fdedc33c5b8d38b9208b350f8accf57ee | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/b54976c81a6b8cae311b75be1a4cda444689bca0 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/ada5ded765f059a6e3036e69ca350449442af0fc | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/fd3a7bf0d988b0878a1957df150edb35f81db87e | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/eb0c7fda59cf650076f8ed5b949a6c8441aa3606 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/a2d326b3f6d470ea4bfde00245794e0dc6dbbc3d | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/0a6a5eecc92c13f936d8d90975116d6bbdf4f876 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.