Commit 60d6d22d authored by Kees Cook's avatar Kees Cook Committed by Martin K. Petersen
Browse files

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: default avatarKees Cook <keescook@chromium.org>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent 092b4558

drivers/scsi/dpt_i2o.c

+14 −7
Original line number Diff line number Diff line
@@ -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;

}

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