linux/net/kcm
Michal Luczaj 9063de636c kcm: Fix splice support
Flags passed in for splice() syscall should not end up in
skb_recv_datagram(). As SPLICE_F_NONBLOCK == MSG_PEEK, kernel gets
confused: skb isn't unlinked from a receive queue, while strp_msg::offset
and strp_msg::full_len are updated.

Unbreak the logic a bit more by mapping both O_NONBLOCK and
SPLICE_F_NONBLOCK to MSG_DONTWAIT. This way we align with man splice(2) in
regard to errno EAGAIN:

   SPLICE_F_NONBLOCK was specified in flags or one of the file descriptors
   had been marked as nonblocking (O_NONBLOCK), and the operation would
   block.

Fixes: 5121197ecc ("kcm: close race conditions on sk_receive_queue")
Fixes: 91687355b9 ("kcm: Splice support")
Signed-off-by: Michal Luczaj <mhal@rbox.co>
Link: https://patch.msgid.link/20250725-kcm-splice-v1-1-9a725ad2ee71@rbox.co
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-30 18:01:26 -07:00
..
Kconfig treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
Makefile treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
kcmproc.c net: kcm: kcmproc.c: Fix RCU list suspicious usage warning 2020-03-16 17:14:02 -07:00
kcmsock.c kcm: Fix splice support 2025-07-30 18:01:26 -07:00