From: Magnus Karlsson magnus.karlsson@intel.com
[ Upstream commit 58ca14ed98c87cfe0d1408cc65a9745d9e9b7a56 ]
Fix an issue in XDP_SHARED_UMEM mode together with aligned mode where packets are corrupted for the second and any further sockets bound to the same umem. In other words, this does not affect the first socket bound to the umem. The culprit for this bug is that the initialization of the DMA addresses for the pre-populated xsk buffer pool entries was not performed for any socket but the first one bound to the umem. Only the linear array of DMA addresses was populated. Fix this by populating the DMA addresses in the xsk buffer pool for every socket bound to the same umem.
Fixes: 94033cd8e73b8 ("xsk: Optimize for aligned case") Reported-by: Alasdair McWilliam alasdair.mcwilliam@outlook.com Reported-by: Intrusion Shield Team dnevil@intrusion.com Signed-off-by: Magnus Karlsson magnus.karlsson@intel.com Signed-off-by: Daniel Borkmann daniel@iogearbox.net Tested-by: Alasdair McWilliam alasdair.mcwilliam@outlook.com Acked-by: Maciej Fijalkowski maciej.fijalkowski@intel.com Link: https://lore.kernel.org/xdp-newbies/6205E10C-292E-4995-9D10-409649354226@out... Link: https://lore.kernel.org/bpf/20220812113259.531-1-magnus.karlsson@gmail.com Signed-off-by: Sasha Levin sashal@kernel.org --- net/xdp/xsk_buff_pool.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-)
diff --git a/net/xdp/xsk_buff_pool.c b/net/xdp/xsk_buff_pool.c index f70112176b7c1..a71a8c6edf553 100644 --- a/net/xdp/xsk_buff_pool.c +++ b/net/xdp/xsk_buff_pool.c @@ -379,6 +379,16 @@ static void xp_check_dma_contiguity(struct xsk_dma_map *dma_map)
static int xp_init_dma_info(struct xsk_buff_pool *pool, struct xsk_dma_map *dma_map) { + if (!pool->unaligned) { + u32 i; + + for (i = 0; i < pool->heads_cnt; i++) { + struct xdp_buff_xsk *xskb = &pool->heads[i]; + + xp_init_xskb_dma(xskb, pool, dma_map->dma_pages, xskb->orig_addr); + } + } + pool->dma_pages = kvcalloc(dma_map->dma_pages_cnt, sizeof(*pool->dma_pages), GFP_KERNEL); if (!pool->dma_pages) return -ENOMEM; @@ -428,12 +438,6 @@ int xp_dma_map(struct xsk_buff_pool *pool, struct device *dev,
if (pool->unaligned) xp_check_dma_contiguity(dma_map); - else - for (i = 0; i < pool->heads_cnt; i++) { - struct xdp_buff_xsk *xskb = &pool->heads[i]; - - xp_init_xskb_dma(xskb, pool, dma_map->dma_pages, xskb->orig_addr); - }
err = xp_init_dma_info(pool, dma_map); if (err) {