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USB: host: Eliminate NULL dereference

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The test above allows std to be NULL, so check that std is not NULL before
doing the dereference.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@r exists@
expression E,E1;
identifier f;
statement S1,S2,S3;
@@

if ((E == NULL && ...) || ...)
{
  ... when != if (...) S1 else S2
      when != E = E1
* E->f
  ... when any
}
else S3
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Julia Lawall 2010-05-27 18:10:08 +02:00 committed by Greg Kroah-Hartman
parent 6e1c3b467f
commit dc6eb27bdd
1 changed files with 1 additions and 1 deletions
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2
drivers/usb/host/whci/qset.c
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@ -475,7 +475,7 @@ static int qset_add_urb_sg(struct whc *whc, struct whc_qset *qset, struct urb *u
|| (prev_end & (WHCI_PAGE_SIZE-1)) || (prev_end & (WHCI_PAGE_SIZE-1))
|| (dma_addr & (WHCI_PAGE_SIZE-1)) || (dma_addr & (WHCI_PAGE_SIZE-1))
|| std->len + WHCI_PAGE_SIZE > QTD_MAX_XFER_SIZE) { || std->len + WHCI_PAGE_SIZE > QTD_MAX_XFER_SIZE) {
if (std->len % qset->max_packet != 0) if (std && std->len % qset->max_packet != 0)
return -EINVAL; return -EINVAL;
std = qset_new_std(whc, qset, urb, mem_flags); std = qset_new_std(whc, qset, urb, mem_flags);
if (std == NULL) { if (std == NULL) {