0.0
NA
CVE-2025-39923
dmaengine: qcom: bam_dma: Fix DT error handling for num-channels/ees
Description

In the Linux kernel, the following vulnerability has been resolved: dmaengine: qcom: bam_dma: Fix DT error handling for num-channels/ees When we don't have a clock specified in the device tree, we have no way to ensure the BAM is on. This is often the case for remotely-controlled or remotely-powered BAM instances. In this case, we need to read num-channels from the DT to have all the necessary information to complete probing. However, at the moment invalid device trees without clock and without num-channels still continue probing, because the error handling is missing return statements. The driver will then later try to read the number of channels from the registers. This is unsafe, because it relies on boot firmware and lucky timing to succeed. Unfortunately, the lack of proper error handling here has been abused for several Qualcomm SoCs upstream, causing early boot crashes in several situations [1, 2]. Avoid these early crashes by erroring out when any of the required DT properties are missing. Note that this will break some of the existing DTs upstream (mainly BAM instances related to the crypto engine). However, clearly these DTs have never been tested properly, since the error in the kernel log was just ignored. It's safer to disable the crypto engine for these broken DTBs. [1]: https://lore.kernel.org/r/[email protected]/ [2]: https://lore.kernel.org/r/[email protected]/

INFO

Published Date :

Oct. 1, 2025, 8:15 a.m.

Last Modified :

Oct. 1, 2025, 8:15 a.m.

Remotely Exploit :

No

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products

The following products are affected by CVE-2025-39923 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

Solution
Fix missing return statements in DT error handling to prevent boot crashes.
  • Apply the kernel patch for dmaengine: qcom: bam_dma.
  • Ensure clock and num-channels are in the device tree.
  • Update device tree bindings if necessary.
  • Disable crypto engine for broken device trees.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2025-39923 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2025-39923 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2025-39923 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2025-39923 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Oct. 01, 2025

    Action Type Old Value New Value
    Added Description In the Linux kernel, the following vulnerability has been resolved: dmaengine: qcom: bam_dma: Fix DT error handling for num-channels/ees When we don't have a clock specified in the device tree, we have no way to ensure the BAM is on. This is often the case for remotely-controlled or remotely-powered BAM instances. In this case, we need to read num-channels from the DT to have all the necessary information to complete probing. However, at the moment invalid device trees without clock and without num-channels still continue probing, because the error handling is missing return statements. The driver will then later try to read the number of channels from the registers. This is unsafe, because it relies on boot firmware and lucky timing to succeed. Unfortunately, the lack of proper error handling here has been abused for several Qualcomm SoCs upstream, causing early boot crashes in several situations [1, 2]. Avoid these early crashes by erroring out when any of the required DT properties are missing. Note that this will break some of the existing DTs upstream (mainly BAM instances related to the crypto engine). However, clearly these DTs have never been tested properly, since the error in the kernel log was just ignored. It's safer to disable the crypto engine for these broken DTBs. [1]: https://lore.kernel.org/r/[email protected]/ [2]: https://lore.kernel.org/r/[email protected]/
    Added Reference https://git.kernel.org/stable/c/0ff9df758af7022d749718fb6b8385cc5693acf3
    Added Reference https://git.kernel.org/stable/c/1fc14731f0be4885e60702b9596d14d9a79cf053
    Added Reference https://git.kernel.org/stable/c/5068b5254812433e841a40886e695633148d362d
    Added Reference https://git.kernel.org/stable/c/555bd16351a35c79efb029a196975a5a27f7fbc4
    Added Reference https://git.kernel.org/stable/c/ebf6c7c908e5999531c3517289598f187776124f
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
No CVSS metrics available for this vulnerability.