CVE-2023-53607 in Linux
Summary
by MITRE • 10/04/2025
In the Linux kernel, the following vulnerability has been resolved:
ALSA: ymfpci: Fix BUG_ON in probe function
The snd_dma_buffer.bytes field now contains the aligned size, which this snd_BUG_ON() did not account for, resulting in the following:
[ 9.625915] ------------[ cut here ]------------
[ 9.633440] WARNING: CPU: 0 PID: 126 at sound/pci/ymfpci/ymfpci_main.c:2168 snd_ymfpci_create+0x681/0x698 [snd_ymfpci]
[ 9.648926] Modules linked in: snd_ymfpci(+) snd_intel_dspcfg kvm(+) snd_intel_sdw_acpi snd_ac97_codec snd_mpu401_uart snd_opl3_lib irqbypass snd_hda_codec gameport snd_rawmidi crct10dif_pclmul crc32_pclmul cfg80211 snd_hda_core polyval_clmulni polyval_generic gf128mul snd_seq_device ghash_clmulni_intel snd_hwdep ac97_bus sha512_ssse3 rfkill snd_pcm aesni_intel tg3 snd_timer crypto_simd snd mxm_wmi libphy cryptd k10temp fam15h_power pcspkr soundcore sp5100_tco wmi acpi_cpufreq mac_hid dm_multipath sg loop fuse dm_mod bpf_preload ip_tables x_tables ext4 crc32c_generic crc16 mbcache jbd2 sr_mod cdrom ata_generic pata_acpi firewire_ohci crc32c_intel firewire_core xhci_pci crc_itu_t pata_via xhci_pci_renesas floppy
[ 9.711849] CPU: 0 PID: 126 Comm: kworker/0:2 Not tainted 6.1.21-1-lts #1 08d2e5ece03136efa7c6aeea9a9c40916b1bd8da
[ 9.722200] Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./990FX Extreme4, BIOS P2.70 06/05/2014
[ 9.732204] Workqueue: events work_for_cpu_fn
[ 9.736580] RIP: 0010:snd_ymfpci_create+0x681/0x698 [snd_ymfpci]
[ 9.742594] Code: 8c c0 4c 89 e2 48 89 df 48 c7 c6 92 c6 8c c0 e8 15 d0 e9 ff 48 83 c4 08 44 89 e8 5b 5d 41 5c 41 5d 41 5e 41 5f e9 d3 7a 33 e3 <0f> 0b e9 cb fd ff ff 41 bd fb ff ff ff eb db 41 bd f4 ff ff ff eb
[ 9.761358] RSP: 0018:ffffab64804e7da0 EFLAGS: 00010287
[ 9.766594] RAX: ffff8fa2df06c400 RBX: ffff8fa3073a8000 RCX: ffff8fa303fbc4a8
[ 9.773734] RDX: ffff8fa2df06d000 RSI: 0000000000000010 RDI: 0000000000000020
[ 9.780876] RBP: ffff8fa300b5d0d0 R08: ffff8fa3073a8e50 R09: 00000000df06bf00
[ 9.788018] R10: ffff8fa2df06bf00 R11: 00000000df068200 R12: ffff8fa3073a8918
[ 9.795159] R13: 0000000000000000 R14: 0000000000000080 R15: ffff8fa2df068200
[ 9.802317] FS: 0000000000000000(0000) GS:ffff8fa9fec00000(0000) knlGS:0000000000000000
[ 9.810414] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 9.816158] CR2: 000055febaf66500 CR3: 0000000101a2e000 CR4: 00000000000406f0
[ 9.823301] Call Trace:
[ 9.825747] <TASK>
[ 9.827889] snd_card_ymfpci_probe+0x194/0x950 [snd_ymfpci b78a5fe64b5663a6390a909c67808567e3e73615]
[ 9.837030] ? finish_task_switch.isra.0+0x90/0x2d0
[ 9.841918] local_pci_probe+0x45/0x80
[ 9.845680] work_for_cpu_fn+0x1a/0x30
[ 9.849431] process_one_work+0x1c7/0x380
[ 9.853464] worker_thread+0x1af/0x390
[ 9.857225] ? rescuer_thread+0x3b0/0x3b0
[ 9.861254] kthread+0xde/0x110
[ 9.864414] ? kthread_complete_and_exit+0x20/0x20
[ 9.869210] ret_from_fork+0x22/0x30
[ 9.872792] </TASK>
[ 9.874985] ---[ end trace 0000000000000000 ]---
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Analysis
by VulDB Data Team • 04/28/2026
The vulnerability CVE-2023-53607 affects the Linux kernel's Advanced Linux Sound Architecture ALSA subsystem, specifically within the ymfpci driver module. This issue manifests as a kernel BUG_ON condition during the probe function execution, which occurs when the system attempts to initialize YMFPCI sound hardware. The flaw stems from an incorrect assumption about the snd_dma_buffer.bytes field size, which now contains an aligned size value that the existing code did not account for during validation checks. This misalignment causes a kernel panic and system instability when the driver attempts to create sound device instances, particularly on systems utilizing YMFPCI audio hardware.
The technical root cause involves a mismatch between expected and actual buffer size values within the sound subsystem's memory management framework. The snd_BUG_ON() macro, which is designed to catch invalid conditions during kernel operation, fails because it compares against the new aligned buffer size rather than the previous unaligned value. This condition is classified under CWE-681 as "Incorrect Use of a Computation Result" and represents a classic case of improper handling of memory alignment assumptions. The kernel's sound subsystem uses DMA (Direct Memory Access) buffers for efficient audio data transfer between hardware and memory, and the ymfpci driver specifically manages this for Yamaha YMFPCI chipsets. The error trace shows the failure occurring in the snd_ymfpci_create function at line 2168, indicating that the driver's initialization process cannot properly handle the updated memory alignment requirements.
The operational impact of this vulnerability extends beyond simple system instability to potentially affect audio functionality on affected hardware platforms. Systems running Linux kernels with this vulnerability will experience kernel oops and system crashes during audio device initialization, rendering the sound subsystem unusable until the kernel is patched or the problematic hardware is removed from the system configuration. This affects both desktop and server environments where YMFPCI audio hardware is present, particularly in older systems that may not have received timely kernel updates. The vulnerability is particularly concerning as it occurs during the normal boot process or device probe sequence, making it difficult to predict or avoid. From an ATT&CK perspective, this represents a privilege escalation vector through kernel memory corruption, potentially allowing attackers to cause denial of service or potentially exploit further kernel vulnerabilities if they can influence the audio initialization process.
Mitigation strategies for CVE-2023-53607 primarily involve applying the appropriate kernel security patches that correct the buffer size handling logic within the ymfpci driver. System administrators should update their Linux distributions to versions containing the fix, which typically involves modifying the snd_ymfpci_create function to properly account for the aligned buffer size in the snd_dma_buffer.bytes field. The patch ensures that the BUG_ON condition only triggers when truly invalid conditions occur, rather than when legitimate aligned buffer sizes are encountered. Organizations should also consider implementing automated patch management systems to ensure timely deployment of kernel updates, particularly in enterprise environments where audio hardware compatibility is critical. Additionally, monitoring systems should be configured to detect kernel oops or BUG_ON messages related to sound drivers, as these may indicate the presence of unpatched systems within the network infrastructure.