scsi: dpt_i2o: Remove VLA usage

On the quest to remove all VLAs from the kernel[1] this moves the
sg_list variable off the stack, as already done for other allocated
buffers in adpt_i2o_passthru(). Additionally consolidates the error path
for kfree().

[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Kees Cook 2018-05-02 15:21:38 -07:00 committed by Martin K. Petersen
parent 092b45583c
commit 60d6d22d85

View File

@ -1706,7 +1706,7 @@ static int adpt_i2o_passthru(adpt_hba* pHba, u32 __user *arg)
u32 reply_size = 0;
u32 __user *user_msg = arg;
u32 __user * user_reply = NULL;
void *sg_list[pHba->sg_tablesize];
void **sg_list = NULL;
u32 sg_offset = 0;
u32 sg_count = 0;
int sg_index = 0;
@ -1748,19 +1748,23 @@ static int adpt_i2o_passthru(adpt_hba* pHba, u32 __user *arg)
msg[2] = 0x40000000; // IOCTL context
msg[3] = adpt_ioctl_to_context(pHba, reply);
if (msg[3] == (u32)-1) {
kfree(reply);
return -EBUSY;
rcode = -EBUSY;
goto free;
}
memset(sg_list,0, sizeof(sg_list[0])*pHba->sg_tablesize);
sg_list = kcalloc(pHba->sg_tablesize, sizeof(*sg_list), GFP_KERNEL);
if (!sg_list) {
rcode = -ENOMEM;
goto free;
}
if(sg_offset) {
// TODO add 64 bit API
struct sg_simple_element *sg = (struct sg_simple_element*) (msg+sg_offset);
sg_count = (size - sg_offset*4) / sizeof(struct sg_simple_element);
if (sg_count > pHba->sg_tablesize){
printk(KERN_DEBUG"%s:IOCTL SG List too large (%u)\n", pHba->name,sg_count);
kfree (reply);
return -EINVAL;
rcode = -EINVAL;
goto free;
}
for(i = 0; i < sg_count; i++) {
@ -1879,7 +1883,6 @@ cleanup:
if (rcode != -ETIME && rcode != -EINTR) {
struct sg_simple_element *sg =
(struct sg_simple_element*) (msg +sg_offset);
kfree (reply);
while(sg_index) {
if(sg_list[--sg_index]) {
dma_free_coherent(&pHba->pDev->dev,
@ -1889,6 +1892,10 @@ cleanup:
}
}
}
free:
kfree(sg_list);
kfree(reply);
return rcode;
}