Executive brief
A vulnerability in the Linux kernel's Infineon TPM driver could allow a local attacker to cause a resource leak. The Trusted Platform Module (TPM) is a hardware component used for secure operations like disk encryption and identity verification. If this component fails to release its 'locality' (a hardware-level access lock), it could lead to system instability or prevent other security processes from accessing the TPM.
Technical details
A vulnerability in the tpm_i2c_infineon driver in the Linux kernel stems from improper error handling in the tpm_tis_i2c_send() function. When get_burstcount() returns an error (such as -EBUSY on timeout), the function returns immediately without releasing the TPM locality acquired at the start of the operation. This results in a locality leak, which can prevent subsequent TPM operations or other system components from correctly interacting with the hardware. The fix introduces a jump to an error label to ensure proper cleanup and locality release.
Affected products
- Linux Linux Kernel aad628c1d91a
Timeline
- 2026-05-27: disclosed
- 2026-05-27: advisory
References
- https://git.kernel.org/stable/c/1a22048c1117cdfac185ba450aba67ed6b65dc87
- https://git.kernel.org/stable/c/1bb8f8826d0748b4b92a98fb6b6dfe52081739f5
- https://git.kernel.org/stable/c/2f7a665e1323359d99c74301d1e180f5e2c40181
- https://git.kernel.org/stable/c/8f124c5582d443ac9fb690db26d08cab5d6ba76e
- https://git.kernel.org/stable/c/948966e546f29af04391d98b8e378e4a7670c1c1
- https://git.kernel.org/stable/c/a61b8412e3eb8b71646dba867e8252d8560a1a27
- https://git.kernel.org/stable/c/bbd6e97c836cbeb9606d7b7e5dcf8a1d89525713