[SCSI] dpt_i2o: several use after free issues

adpt_i2o_delete_hba() calls kfree() so we have to save "pHba->next"
before calling it.  Also inside adpt_i2o_delete_hba() itself, there
was another use after free bug which I fixed by moving the kfree()
down a line.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

diff --git a/drivers/scsi/dpt_i2o.c b/drivers/scsi/dpt_i2o.c
index 4967643..0435d04 100644 (file)
--- a/drivers/scsi/dpt_i2o.c
+++ b/drivers/scsi/dpt_i2o.c
@@ -188,7 +188,8 @@ MODULE_DEVICE_TABLE(pci,dptids);
 static int adpt_detect(struct scsi_host_template* sht)
 {
        struct pci_dev *pDev = NULL;
-       adpt_hba* pHba;
+       adpt_hba *pHba;
+       adpt_hba *next;
 
        PINFO("Detecting Adaptec I2O RAID controllers...\n");
 
@@ -206,7 +207,8 @@ static int adpt_detect(struct scsi_host_template* sht)
        }
 
        /* In INIT state, Activate IOPs */
-       for (pHba = hba_chain; pHba; pHba = pHba->next) {
+       for (pHba = hba_chain; pHba; pHba = next) {
+               next = pHba->next;
                // Activate does get status , init outbound, and get hrt
                if (adpt_i2o_activate_hba(pHba) < 0) {
                        adpt_i2o_delete_hba(pHba);
@@ -243,7 +245,8 @@ rebuild_sys_tab:
        PDEBUG("HBA's in OPERATIONAL state\n");
 
        printk("dpti: If you have a lot of devices this could take a few minutes.\n");
-       for (pHba = hba_chain; pHba; pHba = pHba->next) {
+       for (pHba = hba_chain; pHba; pHba = next) {
+               next = pHba->next;
                printk(KERN_INFO"%s: Reading the hardware resource table.\n", pHba->name);
                if (adpt_i2o_lct_get(pHba) < 0){
                        adpt_i2o_delete_hba(pHba);
@@ -263,7 +266,8 @@ rebuild_sys_tab:
                adpt_sysfs_class = NULL;
        }
 
-       for (pHba = hba_chain; pHba; pHba = pHba->next) {
+       for (pHba = hba_chain; pHba; pHba = next) {
+               next = pHba->next;
                if (adpt_scsi_host_alloc(pHba, sht) < 0){
                        adpt_i2o_delete_hba(pHba);
                        continue;
@@ -1229,11 +1233,10 @@ static void adpt_i2o_delete_hba(adpt_hba* pHba)
                }
        }
        pci_dev_put(pHba->pDev);
-       kfree(pHba);
-
        if (adpt_sysfs_class)
                device_destroy(adpt_sysfs_class,
                                MKDEV(DPTI_I2O_MAJOR, pHba->unit));
+       kfree(pHba);
 
        if(hba_count <= 0){
                unregister_chrdev(DPTI_I2O_MAJOR, DPT_DRIVER);