e.kubanski 65d3c57061 xsk: Fix race condition in AF_XDP generic RX path ... [ Upstream commit a1356ac774 ] Move rx_lock from xsk_socket to xsk_buff_pool. Fix synchronization for shared umem mode in generic RX path where multiple sockets share single xsk_buff_pool. RX queue is exclusive to xsk_socket, while FILL queue can be shared between multiple sockets. This could result in race condition where two CPU cores access RX path of two different sockets sharing the same umem. Protect both queues by acquiring spinlock in shared xsk_buff_pool. Lock contention may be minimized in the future by some per-thread FQ buffering. It's safe and necessary to move spin_lock_bh(rx_lock) after xsk_rcv_check(): * xs->pool and spinlock_init is synchronized by xsk_bind() -> xsk_is_bound() memory barriers. * xsk_rcv_check() may return true at the moment of xsk_release() or xsk_unbind_dev(), however this will not cause any data races or race conditions. xsk_unbind_dev() removes xdp socket from all maps and waits for completion of all outstanding rx operations. Packets in RX path will either complete safely or drop. Signed-off-by: Eryk Kubanski <e.kubanski@partner.samsung.com> Fixes: bf0bdd1343 ("xdp: fix race on generic receive path") Acked-by: Magnus Karlsson <magnus.karlsson@intel.com> Link: https://patch.msgid.link/20250416101908.10919-1-e.kubanski@partner.samsung.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2025-05-09 09:50:38 +02:00
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Kconfig
Makefile
xdp_umem.c	xsk: Require XDP_UMEM_TX_METADATA_LEN to actuate tx_metadata_len	2024-07-25 11:57:27 +02:00
xdp_umem.h
xsk_buff_pool.c	xsk: Fix race condition in AF_XDP generic RX path	2025-05-09 09:50:38 +02:00
xsk_diag.c	sock_diag: add module pointer to "struct sock_diag_handler"	2024-01-23 15:13:54 +01:00
xsk_queue.c	xdp: Fix zero-size allocation warning in xskq_create()	2023-10-09 16:13:29 +02:00
xsk_queue.h	xsk: Bump xsk_queue::queue_empty_descs in xp_can_alloc()	2024-09-05 15:56:49 +02:00
xsk.c	xsk: Fix race condition in AF_XDP generic RX path	2025-05-09 09:50:38 +02:00
xsk.h
xskmap.c	xsk: fix OOB map writes when deleting elements	2024-12-14 20:03:31 +01:00