From c8c12792d5fe11375af54c6bbbbebdda105eb933 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Thu, 17 Oct 2019 20:39:23 +0100 Subject: [PATCH] scsi: sg: sg_read(): get rid of access_ok()/__copy_..._user() Use copy_..._user() instead, both in sg_read() and in sg_read_oxfer(). And don't open-code memdup_user()... Link: https://lore.kernel.org/r/20191017193925.25539-6-viro@ZenIV.linux.org.uk Signed-off-by: Al Viro Acked-by: Douglas Gilbert Signed-off-by: Martin K. Petersen --- drivers/scsi/sg.c | 18 ++++++------------ 1 file changed, 6 insertions(+), 12 deletions(-) diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index 3702f66..9f6534a 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -429,16 +429,10 @@ sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos) SCSI_LOG_TIMEOUT(3, sg_printk(KERN_INFO, sdp, "sg_read: count=%d\n", (int) count)); - if (!access_ok(buf, count)) - return -EFAULT; if (sfp->force_packid && (count >= SZ_SG_HEADER)) { - old_hdr = kmalloc(SZ_SG_HEADER, GFP_KERNEL); - if (!old_hdr) - return -ENOMEM; - if (__copy_from_user(old_hdr, buf, SZ_SG_HEADER)) { - retval = -EFAULT; - goto free_old_hdr; - } + old_hdr = memdup_user(buf, SZ_SG_HEADER); + if (IS_ERR(old_hdr)) + return PTR_ERR(old_hdr); if (old_hdr->reply_len < 0) { if (count >= SZ_SG_IO_HDR) { sg_io_hdr_t __user *p = (void __user *)buf; @@ -529,7 +523,7 @@ sg_read(struct file *filp, char __user *buf, size_t count, loff_t * ppos) /* Now copy the result back to the user buffer. */ if (count >= SZ_SG_HEADER) { - if (__copy_to_user(buf, old_hdr, SZ_SG_HEADER)) { + if (copy_to_user(buf, old_hdr, SZ_SG_HEADER)) { retval = -EFAULT; goto free_old_hdr; } @@ -1960,12 +1954,12 @@ sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer) num = 1 << (PAGE_SHIFT + schp->page_order); for (k = 0; k < schp->k_use_sg && schp->pages[k]; k++) { if (num > num_read_xfer) { - if (__copy_to_user(outp, page_address(schp->pages[k]), + if (copy_to_user(outp, page_address(schp->pages[k]), num_read_xfer)) return -EFAULT; break; } else { - if (__copy_to_user(outp, page_address(schp->pages[k]), + if (copy_to_user(outp, page_address(schp->pages[k]), num)) return -EFAULT; num_read_xfer -= num; -- 2.7.4