* [PATCH net v2] udp: fix skb_copy_and_csum_datagram with odd segment sizes
@ 2021-02-03 19:29 Willem de Bruijn
2021-02-03 20:54 ` Alexander Duyck
` (2 more replies)
0 siblings, 3 replies; 4+ messages in thread
From: Willem de Bruijn @ 2021-02-03 19:29 UTC (permalink / raw)
To: netdev
Cc: davem, kuba, oliver.graute, sagi, viro, hch, alexander.duyck,
eric.dumazet, Willem de Bruijn
From: Willem de Bruijn <willemb@google.com>
When iteratively computing a checksum with csum_block_add, track the
offset "pos" to correctly rotate in csum_block_add when offset is odd.
The open coded implementation of skb_copy_and_csum_datagram did this.
With the switch to __skb_datagram_iter calling csum_and_copy_to_iter,
pos was reinitialized to 0 on each call.
Bring back the pos by passing it along with the csum to the callback.
Changes v1->v2
- pass csum value, instead of csump pointer (Alexander Duyck)
Link: https://lore.kernel.org/netdev/20210128152353.GB27281@optiplex/
Fixes: 950fcaecd5cc ("datagram: consolidate datagram copy to iter helpers")
Reported-by: Oliver Graute <oliver.graute@gmail.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
---
include/linux/uio.h | 8 +++++++-
lib/iov_iter.c | 24 ++++++++++++++----------
net/core/datagram.c | 12 ++++++++++--
3 files changed, 31 insertions(+), 13 deletions(-)
diff --git a/include/linux/uio.h b/include/linux/uio.h
index 72d88566694e..27ff8eb786dc 100644
--- a/include/linux/uio.h
+++ b/include/linux/uio.h
@@ -260,7 +260,13 @@ static inline void iov_iter_reexpand(struct iov_iter *i, size_t count)
{
i->count = count;
}
-size_t csum_and_copy_to_iter(const void *addr, size_t bytes, void *csump, struct iov_iter *i);
+
+struct csum_state {
+ __wsum csum;
+ size_t off;
+};
+
+size_t csum_and_copy_to_iter(const void *addr, size_t bytes, void *csstate, struct iov_iter *i);
size_t csum_and_copy_from_iter(void *addr, size_t bytes, __wsum *csum, struct iov_iter *i);
bool csum_and_copy_from_iter_full(void *addr, size_t bytes, __wsum *csum, struct iov_iter *i);
size_t hash_and_copy_to_iter(const void *addr, size_t bytes, void *hashp,
diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index a21e6a5792c5..f0b2ccb1bb01 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -592,14 +592,15 @@ static __wsum csum_and_memcpy(void *to, const void *from, size_t len,
}
static size_t csum_and_copy_to_pipe_iter(const void *addr, size_t bytes,
- __wsum *csum, struct iov_iter *i)
+ struct csum_state *csstate,
+ struct iov_iter *i)
{
struct pipe_inode_info *pipe = i->pipe;
unsigned int p_mask = pipe->ring_size - 1;
+ __wsum sum = csstate->csum;
+ size_t off = csstate->off;
unsigned int i_head;
size_t n, r;
- size_t off = 0;
- __wsum sum = *csum;
if (!sanity(i))
return 0;
@@ -621,7 +622,8 @@ static size_t csum_and_copy_to_pipe_iter(const void *addr, size_t bytes,
i_head++;
} while (n);
i->count -= bytes;
- *csum = sum;
+ csstate->csum = sum;
+ csstate->off = off;
return bytes;
}
@@ -1522,18 +1524,19 @@ bool csum_and_copy_from_iter_full(void *addr, size_t bytes, __wsum *csum,
}
EXPORT_SYMBOL(csum_and_copy_from_iter_full);
-size_t csum_and_copy_to_iter(const void *addr, size_t bytes, void *csump,
+size_t csum_and_copy_to_iter(const void *addr, size_t bytes, void *_csstate,
struct iov_iter *i)
{
+ struct csum_state *csstate = _csstate;
const char *from = addr;
- __wsum *csum = csump;
__wsum sum, next;
- size_t off = 0;
+ size_t off;
if (unlikely(iov_iter_is_pipe(i)))
- return csum_and_copy_to_pipe_iter(addr, bytes, csum, i);
+ return csum_and_copy_to_pipe_iter(addr, bytes, _csstate, i);
- sum = *csum;
+ sum = csstate->csum;
+ off = csstate->off;
if (unlikely(iov_iter_is_discard(i))) {
WARN_ON(1); /* for now */
return 0;
@@ -1561,7 +1564,8 @@ size_t csum_and_copy_to_iter(const void *addr, size_t bytes, void *csump,
off += v.iov_len;
})
)
- *csum = sum;
+ csstate->csum = sum;
+ csstate->off = off;
return bytes;
}
EXPORT_SYMBOL(csum_and_copy_to_iter);
diff --git a/net/core/datagram.c b/net/core/datagram.c
index 81809fa735a7..15ab9ffb27fe 100644
--- a/net/core/datagram.c
+++ b/net/core/datagram.c
@@ -721,8 +721,16 @@ static int skb_copy_and_csum_datagram(const struct sk_buff *skb, int offset,
struct iov_iter *to, int len,
__wsum *csump)
{
- return __skb_datagram_iter(skb, offset, to, len, true,
- csum_and_copy_to_iter, csump);
+ struct csum_state csdata = { .csum = *csump };
+ int ret;
+
+ ret = __skb_datagram_iter(skb, offset, to, len, true,
+ csum_and_copy_to_iter, &csdata);
+ if (ret)
+ return ret;
+
+ *csump = csdata.csum;
+ return 0;
}
/**
--
2.30.0.365.g02bc693789-goog
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH net v2] udp: fix skb_copy_and_csum_datagram with odd segment sizes
2021-02-03 19:29 [PATCH net v2] udp: fix skb_copy_and_csum_datagram with odd segment sizes Willem de Bruijn
@ 2021-02-03 20:54 ` Alexander Duyck
2021-02-04 15:04 ` Eric Dumazet
2021-02-05 4:20 ` patchwork-bot+netdevbpf
2 siblings, 0 replies; 4+ messages in thread
From: Alexander Duyck @ 2021-02-03 20:54 UTC (permalink / raw)
To: Willem de Bruijn
Cc: Netdev, David Miller, Jakub Kicinski, oliver.graute,
Sagi Grimberg, Alexander Viro, Christoph Hellwig, Eric Dumazet,
Willem de Bruijn
On Wed, Feb 3, 2021 at 11:29 AM Willem de Bruijn
<willemdebruijn.kernel@gmail.com> wrote:
>
> From: Willem de Bruijn <willemb@google.com>
>
> When iteratively computing a checksum with csum_block_add, track the
> offset "pos" to correctly rotate in csum_block_add when offset is odd.
>
> The open coded implementation of skb_copy_and_csum_datagram did this.
> With the switch to __skb_datagram_iter calling csum_and_copy_to_iter,
> pos was reinitialized to 0 on each call.
>
> Bring back the pos by passing it along with the csum to the callback.
>
> Changes v1->v2
> - pass csum value, instead of csump pointer (Alexander Duyck)
>
> Link: https://lore.kernel.org/netdev/20210128152353.GB27281@optiplex/
> Fixes: 950fcaecd5cc ("datagram: consolidate datagram copy to iter helpers")
> Reported-by: Oliver Graute <oliver.graute@gmail.com>
> Signed-off-by: Willem de Bruijn <willemb@google.com>
Looks good to me.
Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH net v2] udp: fix skb_copy_and_csum_datagram with odd segment sizes
2021-02-03 19:29 [PATCH net v2] udp: fix skb_copy_and_csum_datagram with odd segment sizes Willem de Bruijn
2021-02-03 20:54 ` Alexander Duyck
@ 2021-02-04 15:04 ` Eric Dumazet
2021-02-05 4:20 ` patchwork-bot+netdevbpf
2 siblings, 0 replies; 4+ messages in thread
From: Eric Dumazet @ 2021-02-04 15:04 UTC (permalink / raw)
To: Willem de Bruijn, netdev
Cc: davem, kuba, oliver.graute, sagi, viro, hch, alexander.duyck,
eric.dumazet, Willem de Bruijn
On 2/3/21 8:29 PM, Willem de Bruijn wrote:
> From: Willem de Bruijn <willemb@google.com>
>
> When iteratively computing a checksum with csum_block_add, track the
> offset "pos" to correctly rotate in csum_block_add when offset is odd.
>
> The open coded implementation of skb_copy_and_csum_datagram did this.
> With the switch to __skb_datagram_iter calling csum_and_copy_to_iter,
> pos was reinitialized to 0 on each call.
>
> Bring back the pos by passing it along with the csum to the callback.
>
> Changes v1->v2
> - pass csum value, instead of csump pointer (Alexander Duyck)
>
> Link: https://lore.kernel.org/netdev/20210128152353.GB27281@optiplex/
> Fixes: 950fcaecd5cc ("datagram: consolidate datagram copy to iter helpers")
> Reported-by: Oliver Graute <oliver.graute@gmail.com>
> Signed-off-by: Willem de Bruijn <willemb@google.com>
> ---
>
Reviewed-by: Eric Dumazet <edumazet@google.com>
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH net v2] udp: fix skb_copy_and_csum_datagram with odd segment sizes
2021-02-03 19:29 [PATCH net v2] udp: fix skb_copy_and_csum_datagram with odd segment sizes Willem de Bruijn
2021-02-03 20:54 ` Alexander Duyck
2021-02-04 15:04 ` Eric Dumazet
@ 2021-02-05 4:20 ` patchwork-bot+netdevbpf
2 siblings, 0 replies; 4+ messages in thread
From: patchwork-bot+netdevbpf @ 2021-02-05 4:20 UTC (permalink / raw)
To: Willem de Bruijn
Cc: netdev, davem, kuba, oliver.graute, sagi, viro, hch,
alexander.duyck, eric.dumazet, willemb
Hello:
This patch was applied to netdev/net.git (refs/heads/master):
On Wed, 3 Feb 2021 14:29:52 -0500 you wrote:
> From: Willem de Bruijn <willemb@google.com>
>
> When iteratively computing a checksum with csum_block_add, track the
> offset "pos" to correctly rotate in csum_block_add when offset is odd.
>
> The open coded implementation of skb_copy_and_csum_datagram did this.
> With the switch to __skb_datagram_iter calling csum_and_copy_to_iter,
> pos was reinitialized to 0 on each call.
>
> [...]
Here is the summary with links:
- [net,v2] udp: fix skb_copy_and_csum_datagram with odd segment sizes
https://git.kernel.org/netdev/net/c/52cbd23a119c
You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2021-02-05 4:21 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-02-03 19:29 [PATCH net v2] udp: fix skb_copy_and_csum_datagram with odd segment sizes Willem de Bruijn
2021-02-03 20:54 ` Alexander Duyck
2021-02-04 15:04 ` Eric Dumazet
2021-02-05 4:20 ` patchwork-bot+netdevbpf
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).