Linux Kernel up to 6.15.5/6.16-rc4 spi qcom_nandc_alloc memory corruption

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.15.5/6.16-rc4. It has been classified as critical. Affected by this issue is the function qcom_nandc_alloc of the component spi. Performing a manipulation results in memory corruption. This vulnerability is reported as CVE-2025-38398. No exploit exists. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 6.15.5/6.16-rc4. This affects the function qcom_nandc_alloc of the component spi. The manipulation with an unknown input leads to a memory corruption vulnerability. CWE is classifying the issue as CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: spi: spi-qpic-snand: reallocate BAM transactions Using the mtd_nandbiterrs module for testing the driver occasionally results in weird things like below. 1. swiotlb mapping fails with the following message: [ 85.926216] qcom_snand 79b0000.spi: swiotlb buffer is full (sz: 4294967294 bytes), total 512 (slots), used 0 (slots) [ 85.932937] qcom_snand 79b0000.spi: failure in mapping desc [ 87.999314] qcom_snand 79b0000.spi: failure to write raw page [ 87.999352] mtd_nandbiterrs: error: write_oob failed (-110) Rebooting the board after this causes a panic due to a NULL pointer dereference. 2. If the swiotlb mapping does not fail, rebooting the board may result in a different panic due to a bad spinlock magic: [ 256.104459] BUG: spinlock bad magic on CPU#3, procd/2241 [ 256.104488] Unable to handle kernel paging request at virtual address ffffffff0000049b ... Investigating the issue revealed that these symptoms are results of memory corruption which is caused by out of bounds access within the driver. The driver uses a dynamically allocated structure for BAM transactions, which structure must have enough space for all possible variations of different flash operations initiated by the driver. The required space heavily depends on the actual number of 'codewords' which is calculated from the pagesize of the actual NAND chip. Although the qcom_nandc_alloc() function allocates memory for the BAM transactions during probe, but since the actual number of 'codewords' is not yet know the allocation is done for one 'codeword' only. Because of this, whenever the driver does a flash operation, and the number of the required transactions exceeds the size of the allocated arrays the driver accesses memory out of the allocated range. To avoid this, change the code to free the initially allocated BAM transactions memory, and allocate a new one once the actual number of 'codewords' required for a given NAND chip is known.

The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2025-38398 since 04/16/2025. The exploitability is told to be easy. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 01/03/2026).

Upgrading to version 6.15.6 or 6.16-rc5 eliminates this vulnerability. Applying the patch 86fb36de1132b560f9305f0c78fa69f459fa0980/d85d0380292a7e618915069c3579ae23c7c80339 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2025-1653). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• IBM QRadar SIEM
• SUSE openSUSE
• RESF Rocky Linux
• Dell Avamar
• Open Source Linux Kernel
• Dell NetWorker
• Dell Secure Connect Gateway

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.15.0
• 6.15.1
• 6.15.2
• 6.15.3
• 6.15.4
• 6.15.5
• 6.16-rc1
• 6.16-rc2
• 6.16-rc3
• 6.16-rc4

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Discussion