| Message ID | 1480926185-19926-1-git-send-email-bianpan2016@163.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 05/12/16 09:23, Pan Bian wrote: > Variable rc is reset in the loop, and its value will be non-negative > during the second and after repeat of the loop. If it fails to allocate > memory then, it may return a non-negative integer, which indicates no > error. This patch fixes the bug, assigning "-ENOMEM" to rc when > kzalloc() or alloc_page() returns NULL, and removing the initialization > of rc outside of the loop. > > v1 is reviewed by: Juergen Gross <jgross@suse.com> Not being a real problem in this case I prefer spelling out explicit "Acked-by:" or "Reviewed-by:" tags myself. So for this version you can have: Reviewed-by: Juergen Gross <jgross@suse.com> Juergen > > Signed-off-by: Pan Bian <bianpan2016@163.com> > --- > drivers/xen/gntalloc.c | 9 ++++++--- > 1 file changed, 6 insertions(+), 3 deletions(-) > > diff --git a/drivers/xen/gntalloc.c b/drivers/xen/gntalloc.c > index 7a47c4c..1bf55a3 100644 > --- a/drivers/xen/gntalloc.c > +++ b/drivers/xen/gntalloc.c > @@ -127,18 +127,21 @@ static int add_grefs(struct ioctl_gntalloc_alloc_gref *op, > struct gntalloc_gref *gref, *next; > > readonly = !(op->flags & GNTALLOC_FLAG_WRITABLE); > - rc = -ENOMEM; > for (i = 0; i < op->count; i++) { > gref = kzalloc(sizeof(*gref), GFP_KERNEL); > - if (!gref) > + if (!gref) { > + rc = -ENOMEM; > goto undo; > + } > list_add_tail(&gref->next_gref, &queue_gref); > list_add_tail(&gref->next_file, &queue_file); > gref->users = 1; > gref->file_index = op->index + i * PAGE_SIZE; > gref->page = alloc_page(GFP_KERNEL|__GFP_ZERO); > - if (!gref->page) > + if (!gref->page) { > + rc = -ENOMEM; > goto undo; > + } > > /* Grant foreign access to the page. */ > rc = gnttab_grant_foreign_access(op->domid, >
On 05/12/16 09:23, Pan Bian wrote: > Variable rc is reset in the loop, and its value will be non-negative > during the second and after repeat of the loop. If it fails to allocate > memory then, it may return a non-negative integer, which indicates no > error. This patch fixes the bug, assigning "-ENOMEM" to rc when > kzalloc() or alloc_page() returns NULL, and removing the initialization > of rc outside of the loop. > > v1 is reviewed by: Juergen Gross <jgross@suse.com> > > Signed-off-by: Pan Bian <bianpan2016@163.com> Commited to xen/tip.git for-linus-4.10 Juergen
diff --git a/drivers/xen/gntalloc.c b/drivers/xen/gntalloc.c index 7a47c4c..1bf55a3 100644 --- a/drivers/xen/gntalloc.c +++ b/drivers/xen/gntalloc.c @@ -127,18 +127,21 @@ static int add_grefs(struct ioctl_gntalloc_alloc_gref *op, struct gntalloc_gref *gref, *next; readonly = !(op->flags & GNTALLOC_FLAG_WRITABLE); - rc = -ENOMEM; for (i = 0; i < op->count; i++) { gref = kzalloc(sizeof(*gref), GFP_KERNEL); - if (!gref) + if (!gref) { + rc = -ENOMEM; goto undo; + } list_add_tail(&gref->next_gref, &queue_gref); list_add_tail(&gref->next_file, &queue_file); gref->users = 1; gref->file_index = op->index + i * PAGE_SIZE; gref->page = alloc_page(GFP_KERNEL|__GFP_ZERO); - if (!gref->page) + if (!gref->page) { + rc = -ENOMEM; goto undo; + } /* Grant foreign access to the page. */ rc = gnttab_grant_foreign_access(op->domid,
Variable rc is reset in the loop, and its value will be non-negative during the second and after repeat of the loop. If it fails to allocate memory then, it may return a non-negative integer, which indicates no error. This patch fixes the bug, assigning "-ENOMEM" to rc when kzalloc() or alloc_page() returns NULL, and removing the initialization of rc outside of the loop. v1 is reviewed by: Juergen Gross <jgross@suse.com> Signed-off-by: Pan Bian <bianpan2016@163.com> --- drivers/xen/gntalloc.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)