CVE-2025-21739

Description

In the Linux kernel, the following vulnerability has been resolved: scsi: ufs: core: Fix use-after free in init error and remove paths devm_blk_crypto_profile_init() registers a cleanup handler to run when the associated (platform-) device is being released. For UFS, the crypto private data and pointers are stored as part of the ufs_hba's data structure 'struct ufs_hba::crypto_profile'. This structure is allocated as part of the underlying ufshcd and therefore Scsi_host allocation. During driver release or during error handling in ufshcd_pltfrm_init(), this structure is released as part of ufshcd_dealloc_host() before the (platform-) device associated with the crypto call above is released. Once this device is released, the crypto cleanup code will run, using the just-released 'struct ufs_hba::crypto_profile'. This causes a use-after-free situation: Call trace: kfree+0x60/0x2d8 (P) kvfree+0x44/0x60 blk_crypto_profile_destroy_callback+0x28/0x70 devm_action_release+0x1c/0x30 release_nodes+0x6c/0x108 devres_release_all+0x98/0x100 device_unbind_cleanup+0x20/0x70 really_probe+0x218/0x2d0 In other words, the initialisation code flow is: platform-device probe ufshcd_pltfrm_init() ufshcd_alloc_host() scsi_host_alloc() allocation of struct ufs_hba creation of scsi-host devices devm_blk_crypto_profile_init() devm registration of cleanup handler using platform-device and during error handling of ufshcd_pltfrm_init() or during driver removal: ufshcd_dealloc_host() scsi_host_put() put_device(scsi-host) release of struct ufs_hba put_device(platform-device) crypto cleanup handler To fix this use-after free, change ufshcd_alloc_host() to register a devres action to automatically cleanup the underlying SCSI device on ufshcd destruction, without requiring explicit calls to ufshcd_dealloc_host(). This way: * the crypto profile and all other ufs_hba-owned resources are destroyed before SCSI (as they've been registered after) * a memleak is plugged in tc-dwc-g210-pci.c remove() as a side-effect * EXPORT_SYMBOL_GPL(ufshcd_dealloc_host) can be removed fully as it's not needed anymore * no future drivers using ufshcd_alloc_host() could ever forget adding the cleanup

Gravité et risque d'exploitation

CVE-2025-21739 obtient un score CVSS de 7.8/10, soit une gravité élevée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.22 %, ce qui la place devant 12.1 % des CVE référencées.

Que faire ?

• Vérifiez si Linux (versions <=6.1.*, <=6.12.*, d76d9d7d1009968dd3a0fc30e5f5ee9fbffc1350, 0, <0c77c0d754fe83cb154715fcfec6c3faef94f207, <9c185beae09a3eb85f54777edafa227f7e03075d, 5.15.209, 6.14, 5.12, <=6.6.*, 6.1.175, 6.13.3, <0dc539b888fb5f56b6eeddd95433eab557d4b0c1, <5.12, 6.12.14, 6.6.135, <f8fb2403ddebb5eea0033d90d9daae4c88749ada, <0a6895c03b1f439236e2d22b1a69ebfc1eb9d5ea, <=*, <=5.15.*, <=6.13.*, <d06eb2620d3bf16056b8b7ea3744dbb5e30512f4) est présent sur votre parc.
• Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
• À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
• Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.

Références

• https://git.kernel.org/stable/c/0a6895c03b1f439236e2d22b1a69ebfc1eb9d5ea
• https://git.kernel.org/stable/c/d06eb2620d3bf16056b8b7ea3744dbb5e30512f4
• https://git.kernel.org/stable/c/0dc539b888fb5f56b6eeddd95433eab557d4b0c1
• https://git.kernel.org/stable/c/0c77c0d754fe83cb154715fcfec6c3faef94f207
• https://git.kernel.org/stable/c/9c185beae09a3eb85f54777edafa227f7e03075d
• https://git.kernel.org/stable/c/f8fb2403ddebb5eea0033d90d9daae4c88749ada