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When a port requiring more headroom is > added to the bridge, br_add_if() can increase dev->needed_headroom > between the two calls. The reserved headroom can then exceed the space > accounted for by alloc_skb(). > > Take one headroom snapshot and use it for both the allocation size and > skb_reserve(). > > Fixes: ed842faeb2bd ("bridge: suppress nd pkts on BR_NEIGH_SUPPRESS ports") > Cc: stable@kernel.org > Reported-by: TencentOS Corvus AI > Assisted-by: tencentos-corvus-ai:hy4-preview This tag is deprecated since commit 1e035297ffda ("docs: remove Assisted-by references"). > Signed-off-by: Jun Yang Reviewed-by: Ido Schimmel