CVE-2025-38585 Information

Aug 20, 2025 cve

Description

In the Linux kernel the following vulnerability has been resolved:

staging: media: atomisp: Fix stack buffer overflow in gmin_get_var_int()

When gmin_get_config_var() calls efi.get_variable() and the EFI variable is larger than the expected buffer size two behaviors combine to create a stack buffer overflow:

  1. gmin_get_config_var() does not return the proper error code when efi.get_variable() fails. It returns the stale ‘ret’ value from earlier operations instead of indicating the EFI failure.

  2. When efi.get_variable() returns EFI_BUFFER_TOO_SMALL it updates out_len to the required buffer size but writes no data to the output buffer. However due to bug 1 gmin_get_var_int() believes the call succeeded.

The caller gmin_get_var_int() then performs:

  • Allocates val[CFG_VAR_NAME_MAX + 1] (65 bytes) on stack
  • Calls gmin_get_config_var(dev is_gmin var val &len) with len=64
  • If EFI variable is >64 bytes efi.get_variable() sets len=required_size
  • Due to bug 1 thinks call succeeded with len=required_size
  • Executes val[len] = 0 writing past end of 65-byte stack buffer

This creates a stack buffer overflow when EFI variables are larger than 64 bytes. Since EFI variables can be controlled by firmware or system configuration this could potentially be exploited for code execution.

Fix the bug by returning proper error codes from gmin_get_config_var() based on EFI status instead of stale ‘ret’ value.

The gmin_get_var_int() function is called during device initialization for camera sensor configuration on Intel Bay Trail and Cherry Trail platforms using the atomisp camera stack.

Reference

https://git.kernel.org/stable/c/1a7a2f59fb2eb0718a0cff1e5822500cefe50ed9 https://git.kernel.org/stable/c/3d672fe065aa00f4d66f42e3c9720f69a3ed43e7 https://git.kernel.org/stable/c/e6d3453a002e89537e6136f6c774659b297a549b https://git.kernel.org/stable/c/ee4cf798202d285dcbe85e4467a094c44f5ed8e6

CNNVD-202508-2149 (Published: 2025-08-19)

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