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| author | Michael S. Tsirkin <mst@redhat.com> | 2009-04-20 01:26:11 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2009-04-21 05:42:46 -0700 |
| commit | 6f26c9a7555e5bcca3560919db9b852015077dae (patch) | |
| tree | 9ca7509cd0cbbdae158b752c234cb23add8370f0 /net | |
| parent | 43b39dcdbdf823a1c0ac1f2aa2d76bd2f210adc8 (diff) | |
| download | linux-stable-6f26c9a7555e5bcca3560919db9b852015077dae.tar.gz linux-stable-6f26c9a7555e5bcca3560919db9b852015077dae.tar.bz2 linux-stable-6f26c9a7555e5bcca3560919db9b852015077dae.zip | |
tun: fix tun_chr_aio_write so that aio works
aio_write gets const struct iovec * but tun_chr_aio_write casts this to struct
iovec * and modifies the iovec. As a result, attempts to use io_submit
to send packets to a tun device fail with weird errors such as EINVAL.
Since tun is the only user of skb_copy_datagram_from_iovec, we can
fix this simply by changing the later so that it does not
touch the iovec passed to it.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/core/datagram.c | 20 | ||||
| -rw-r--r-- | net/core/iovec.c | 7 |
2 files changed, 18 insertions, 9 deletions
diff --git a/net/core/datagram.c b/net/core/datagram.c index 4dbb05cd572b..914d5fa773b4 100644 --- a/net/core/datagram.c +++ b/net/core/datagram.c @@ -435,13 +435,15 @@ EXPORT_SYMBOL(skb_copy_datagram_const_iovec); * @skb: buffer to copy * @offset: offset in the buffer to start copying to * @from: io vector to copy to + * @from_offset: offset in the io vector to start copying from * @len: amount of data to copy to buffer from iovec * * Returns 0 or -EFAULT. - * Note: the iovec is modified during the copy. + * Note: the iovec is not modified during the copy. */ int skb_copy_datagram_from_iovec(struct sk_buff *skb, int offset, - struct iovec *from, int len) + const struct iovec *from, int from_offset, + int len) { int start = skb_headlen(skb); int i, copy = start - offset; @@ -450,11 +452,12 @@ int skb_copy_datagram_from_iovec(struct sk_buff *skb, int offset, if (copy > 0) { if (copy > len) copy = len; - if (memcpy_fromiovec(skb->data + offset, from, copy)) + if (memcpy_fromiovecend(skb->data + offset, from, 0, copy)) goto fault; if ((len -= copy) == 0) return 0; offset += copy; + from_offset += copy; } /* Copy paged appendix. Hmm... why does this look so complicated? */ @@ -473,8 +476,9 @@ int skb_copy_datagram_from_iovec(struct sk_buff *skb, int offset, if (copy > len) copy = len; vaddr = kmap(page); - err = memcpy_fromiovec(vaddr + frag->page_offset + - offset - start, from, copy); + err = memcpy_fromiovecend(vaddr + frag->page_offset + + offset - start, + from, from_offset, copy); kunmap(page); if (err) goto fault; @@ -482,6 +486,7 @@ int skb_copy_datagram_from_iovec(struct sk_buff *skb, int offset, if (!(len -= copy)) return 0; offset += copy; + from_offset += copy; } start = end; } @@ -500,11 +505,14 @@ int skb_copy_datagram_from_iovec(struct sk_buff *skb, int offset, copy = len; if (skb_copy_datagram_from_iovec(list, offset - start, - from, copy)) + from, + from_offset, + copy)) goto fault; if ((len -= copy) == 0) return 0; offset += copy; + from_offset += copy; } start = end; } diff --git a/net/core/iovec.c b/net/core/iovec.c index a215545c0a34..40a76ce19d9f 100644 --- a/net/core/iovec.c +++ b/net/core/iovec.c @@ -147,10 +147,11 @@ int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len) } /* - * For use with ip_build_xmit + * Copy iovec from kernel. Returns -EFAULT on error. */ -int memcpy_fromiovecend(unsigned char *kdata, struct iovec *iov, int offset, - int len) + +int memcpy_fromiovecend(unsigned char *kdata, const struct iovec *iov, + int offset, int len) { /* Skip over the finished iovecs */ while (offset >= iov->iov_len) { |