5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sagi Grimberg <sagi@xxxxxxxxxxx> [ Upstream commit d2d30a376d9cc94c6fb730c58b3e5b7426ecb6de ] We only use the mapping in a single context, so kmap_local is sufficient and cheaper. Make sure to use skb_frag_foreach_page as skb frags may contain compound pages and we need to map page by page. Reported-by: kernel test robot <oliver.sang@xxxxxxxxx> Closes: https://lore.kernel.org/oe-lkp/202406161539.b5ff7b20-oliver.sang@xxxxxxxxx Fixes: 950fcaecd5cc ("datagram: consolidate datagram copy to iter helpers") Signed-off-by: Sagi Grimberg <sagi@xxxxxxxxxxx> Link: https://patch.msgid.link/20240626100008.831849-1-sagi@xxxxxxxxxxx Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- net/core/datagram.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) diff --git a/net/core/datagram.c b/net/core/datagram.c index 1ff8241217a9c..6b7db06eafe68 100644 --- a/net/core/datagram.c +++ b/net/core/datagram.c @@ -440,15 +440,22 @@ static int __skb_datagram_iter(const struct sk_buff *skb, int offset, end = start + skb_frag_size(frag); if ((copy = end - offset) > 0) { - struct page *page = skb_frag_page(frag); - u8 *vaddr = kmap(page); + u32 p_off, p_len, copied; + struct page *p; + u8 *vaddr; if (copy > len) copy = len; - n = INDIRECT_CALL_1(cb, simple_copy_to_iter, - vaddr + skb_frag_off(frag) + offset - start, - copy, data, to); - kunmap(page); + + 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, + vaddr + p_off, p_len, data, to); + kunmap_local(vaddr); + } + offset += n; if (n != copy) goto short_copy; -- 2.43.0
