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authorWillem de Bruijn <willemb@google.com>2021-02-03 22:29:52 +0300
committerJakub Kicinski <kuba@kernel.org>2021-02-05 05:56:56 +0300
commit52cbd23a119c6ebf40a527e53f3402d2ea38eccb (patch)
tree55813d3d72a9cb35ec3e95363e292b8b210682e1 /lib/iov_iter.c
parent1d23a56b0296d29e7047b41fe0a42a001036160d (diff)
downloadlinux-52cbd23a119c6ebf40a527e53f3402d2ea38eccb.tar.xz
udp: fix skb_copy_and_csum_datagram with odd segment sizes
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: Alexander Duyck <alexanderduyck@fb.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20210203192952.1849843-1-willemdebruijn.kernel@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'lib/iov_iter.c')
-rw-r--r--lib/iov_iter.c24
1 files changed, 14 insertions, 10 deletions
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);