diff options
| author | Michael S. Tsirkin <mst@redhat.com> | 2013-06-23 17:19:03 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2013-06-25 16:16:45 -0700 |
| commit | 7e24bfbe43b545b1689a5f134ed83645b9e34b86 (patch) | |
| tree | 74dde1d00b2eb4c739dbe1375853e0e7383ac523 /drivers/net/tun.c | |
| parent | bd8a7036c06cf15779b31a5397d4afcb12be81ea (diff) | |
tun: fix recovery from gup errors
get user pages might fail partially in tun zero copy
mode. To recover we need to put all pages that we got,
but code used a wrong index resulting in double-free
errors.
Reported-by: Brad Hubbard <bhubbard@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/tun.c')
| -rw-r--r-- | drivers/net/tun.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/net/tun.c b/drivers/net/tun.c index bfa9bb48e42d..9c61f8734a40 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -1010,8 +1010,10 @@ static int zerocopy_sg_from_iovec(struct sk_buff *skb, const struct iovec *from, return -EMSGSIZE; num_pages = get_user_pages_fast(base, size, 0, &page[i]); if (num_pages != size) { - for (i = 0; i < num_pages; i++) - put_page(page[i]); + int j; + + for (j = 0; j < num_pages; j++) + put_page(page[i + j]); return -EFAULT; } truesize = size * PAGE_SIZE; |