Linux Kernel up to 6.12.23/6.13.11/6.14.2/6.15-rc1 dmam_free_coherent allocation of resources

Summaryinfo

A vulnerability has been found in Linux Kernel up to 6.12.23/6.13.11/6.14.2/6.15-rc1 and classified as problematic. Affected by this vulnerability is the function dmam_free_coherent. This manipulation causes allocation of resources. This vulnerability appears as CVE-2025-37837. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as problematic was found in Linux Kernel up to 6.12.23/6.13.11/6.14.2/6.15-rc1. Affected by this vulnerability is the function dmam_free_coherent. The manipulation with an unknown input leads to a allocation of resources vulnerability. The CWE definition for the vulnerability is CWE-770. The product allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor. The impact remains unknown. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: iommu/tegra241-cmdqv: Fix warnings due to dmam_free_coherent() Two WARNINGs are observed when SMMU driver rolls back upon failure: arm-smmu-v3.9.auto: Failed to register iommu arm-smmu-v3.9.auto: probe with driver arm-smmu-v3 failed with error -22 ------------[ cut here ]------------ WARNING: CPU: 5 PID: 1 at kernel/dma/mapping.c:74 dmam_free_coherent+0xc0/0xd8 Call trace: dmam_free_coherent+0xc0/0xd8 (P) tegra241_vintf_free_lvcmdq+0x74/0x188 tegra241_cmdqv_remove_vintf+0x60/0x148 tegra241_cmdqv_remove+0x48/0xc8 arm_smmu_impl_remove+0x28/0x60 devm_action_release+0x1c/0x40 ------------[ cut here ]------------ 128 pages are still in use! WARNING: CPU: 16 PID: 1 at mm/page_alloc.c:6902 free_contig_range+0x18c/0x1c8 Call trace: free_contig_range+0x18c/0x1c8 (P) cma_release+0x154/0x2f0 dma_free_contiguous+0x38/0xa0 dma_direct_free+0x10c/0x248 dma_free_attrs+0x100/0x290 dmam_free_coherent+0x78/0xd8 tegra241_vintf_free_lvcmdq+0x74/0x160 tegra241_cmdqv_remove+0x98/0x198 arm_smmu_impl_remove+0x28/0x60 devm_action_release+0x1c/0x40 This is because the LVCMDQ queue memory are managed by devres, while that dmam_free_coherent() is called in the context of devm_action_release(). Jason pointed out that "arm_smmu_impl_probe() has mis-ordered the devres callbacks if ops->device_remove() is going to be manually freeing things that probe allocated": https://lore.kernel.org/linux-iommu/[email protected]/ In fact, tegra241_cmdqv_init_structures() only allocates memory resources which means any failure that it generates would be similar to -ENOMEM, so there is no point in having that "falling back to standard SMMU" routine, as the standard SMMU would likely fail to allocate memory too. Remove the unwind part in tegra241_cmdqv_init_structures(), and return a proper error code to ask SMMU driver to call tegra241_cmdqv_remove() via impl_ops->device_remove(). Then, drop tegra241_vintf_free_lvcmdq() since devres will take care of that.

It is possible to read the advisory at git.kernel.org. This vulnerability is known as CVE-2025-37837 since 04/16/2025. The exploitation appears to be difficult. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 240657 (Ubuntu 25.04 : Linux kernel vulnerabilities (USN-7594-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.12.24, 6.13.12, 6.14.3 or 6.15-rc2 eliminates this vulnerability. Applying the patch e5dd974d6e00704553308ef1a88659f8dcfb39d4/5584dbf393df509159813645a487b1ef76557722/e38ed6908080047d8fa1763d1da86b584f9eb55b/767e22001dfce64cc03b7def1562338591ab6031 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 Tenable (240657). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.12.0
• 6.12.1
• 6.12.2
• 6.12.3
• 6.12.4
• 6.12.5
• 6.12.6
• 6.12.7
• 6.12.8
• 6.12.9
• 6.12.10
• 6.12.11
• 6.12.12
• 6.12.13
• 6.12.14
• 6.12.15
• 6.12.16
• 6.12.17
• 6.12.18
• 6.12.19
• 6.12.20
• 6.12.21
• 6.12.22
• 6.12.23
• 6.13.0
• 6.13.1
• 6.13.2
• 6.13.3
• 6.13.4
• 6.13.5
• 6.13.6
• 6.13.7
• 6.13.8
• 6.13.9
• 6.13.10
• 6.13.11
• 6.14.0
• 6.14.1
• 6.14.2
• 6.15-rc1

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

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