firewire: prevent dropping of completed iso packet header data
The buffer for the header data of completed iso packets has a fixed
size, so it is possible to configure a stream with a big interval
between interrupt packets or with big headers so that this buffer would
overflow. Previously, ohci.c would drop any data that would not fit,
but this could make unsuspecting applications believe that fewer than
the actual number of packets have completed.
Instead of dropping data, add calls to flush_iso_completion() so that
there are as many events as needed to report all of the data.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
diff --git a/drivers/firewire/ohci.c b/drivers/firewire/ohci.c
index 07d3c8d..6325626 100644
--- a/drivers/firewire/ohci.c
+++ b/drivers/firewire/ohci.c
@@ -2689,7 +2689,7 @@
u32 *ctx_hdr;
if (ctx->header_length + ctx->base.header_size > PAGE_SIZE)
- return;
+ flush_iso_completions(ctx);
ctx_hdr = ctx->header + ctx->header_length;
ctx->last_timestamp = (u16)le32_to_cpu((__force __le32)dma_hdr[0]);
@@ -2826,16 +2826,16 @@
sync_it_packet_for_cpu(context, d);
- if (ctx->header_length + 4 < PAGE_SIZE) {
- ctx_hdr = ctx->header + ctx->header_length;
- /* Present this value as big-endian to match the receive code */
- *ctx_hdr = cpu_to_be32(
- ((u32)le16_to_cpu(pd->transfer_status) << 16) |
- le16_to_cpu(pd->res_count));
- ctx->header_length += 4;
- }
+ if (ctx->header_length + 4 > PAGE_SIZE)
+ flush_iso_completions(ctx);
+ ctx_hdr = ctx->header + ctx->header_length;
ctx->last_timestamp = le16_to_cpu(last->res_count);
+ /* Present this value as big-endian to match the receive code */
+ *ctx_hdr = cpu_to_be32((le16_to_cpu(pd->transfer_status) << 16) |
+ le16_to_cpu(pd->res_count));
+ ctx->header_length += 4;
+
if (last->control & cpu_to_le16(DESCRIPTOR_IRQ_ALWAYS))
flush_iso_completions(ctx);