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| author | Jan Beulich <JBeulich@suse.com> | 2018-09-25 02:13:37 -0600 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2018-09-25 10:39:34 -0700 |
| commit | 871088bf92e11efb69bbdbd537e48c0ad4f63729 (patch) | |
| tree | d11b87a3087bb42159cecc05a7c8fbbd3ab3219a /drivers/net/xen-netback | |
| parent | 22f9cde3401077ea450b69bf9b0bba373e12e454 (diff) | |
| download | linux-871088bf92e11efb69bbdbd537e48c0ad4f63729.tar.bz2 | |
xen-netback: handle page straddling in xenvif_set_hash_mapping()
There's no guarantee that the mapping array doesn't cross a page
boundary. Use a second grant copy operation if necessary.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/xen-netback')
| -rw-r--r-- | drivers/net/xen-netback/hash.c | 25 |
1 files changed, 18 insertions, 7 deletions
diff --git a/drivers/net/xen-netback/hash.c b/drivers/net/xen-netback/hash.c index dc9841ea2fff..0ccb021f1e78 100644 --- a/drivers/net/xen-netback/hash.c +++ b/drivers/net/xen-netback/hash.c @@ -334,28 +334,39 @@ u32 xenvif_set_hash_mapping(struct xenvif *vif, u32 gref, u32 len, u32 off) { u32 *mapping = vif->hash.mapping[!vif->hash.mapping_sel]; - struct gnttab_copy copy_op = { + unsigned int nr = 1; + struct gnttab_copy copy_op[2] = {{ .source.u.ref = gref, .source.domid = vif->domid, .dest.domid = DOMID_SELF, .len = len * sizeof(*mapping), .flags = GNTCOPY_source_gref - }; + }}; if ((off + len < off) || (off + len > vif->hash.size) || len > XEN_PAGE_SIZE / sizeof(*mapping)) return XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER; - copy_op.dest.u.gmfn = virt_to_gfn(mapping + off); - copy_op.dest.offset = xen_offset_in_page(mapping + off); + copy_op[0].dest.u.gmfn = virt_to_gfn(mapping + off); + copy_op[0].dest.offset = xen_offset_in_page(mapping + off); + if (copy_op[0].dest.offset + copy_op[0].len > XEN_PAGE_SIZE) { + copy_op[1] = copy_op[0]; + copy_op[1].source.offset = XEN_PAGE_SIZE - copy_op[0].dest.offset; + copy_op[1].dest.u.gmfn = virt_to_gfn(mapping + off + len); + copy_op[1].dest.offset = 0; + copy_op[1].len = copy_op[0].len - copy_op[1].source.offset; + copy_op[0].len = copy_op[1].source.offset; + nr = 2; + } memcpy(mapping, vif->hash.mapping[vif->hash.mapping_sel], vif->hash.size * sizeof(*mapping)); - if (copy_op.len != 0) { - gnttab_batch_copy(©_op, 1); + if (copy_op[0].len != 0) { + gnttab_batch_copy(copy_op, nr); - if (copy_op.status != GNTST_okay) + if (copy_op[0].status != GNTST_okay || + copy_op[nr - 1].status != GNTST_okay) return XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER; } |