5.15-stable review patch. If anyone has any objections, please let me know.
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From: Hugh Dickins hughd@google.com
[ Upstream commit f153831097b4435f963e385304cc0f1acba1c657 ]
X would not start in my old 32-bit partition (and the "n"-handling looks just as wrong on 64-bit, but for whatever reason did not show up there): "n" must be accumulated over all pages before it's added to "offset" and compared with "copy", immediately after the skb_frag_foreach_page() loop.
Fixes: d2d30a376d9c ("net: allow skb_datagram_iter to be called from any context") Signed-off-by: Hugh Dickins hughd@google.com Reviewed-by: Sagi Grimberg sagi@grimberg.me Link: https://patch.msgid.link/fef352e8-b89a-da51-f8ce-04bc39ee6481@google.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/core/datagram.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/net/core/datagram.c b/net/core/datagram.c index 6b7db06eafe68..13f4bf82b2ee8 100644 --- a/net/core/datagram.c +++ b/net/core/datagram.c @@ -447,11 +447,12 @@ static int __skb_datagram_iter(const struct sk_buff *skb, int offset, if (copy > len) copy = len;
+ n = 0; skb_frag_foreach_page(frag, skb_frag_off(frag) + offset - start, copy, p, p_off, p_len, copied) { vaddr = kmap_local_page(p); - n = INDIRECT_CALL_1(cb, simple_copy_to_iter, + n += INDIRECT_CALL_1(cb, simple_copy_to_iter, vaddr + p_off, p_len, data, to); kunmap_local(vaddr); }