netdev - [PATCH v7 net-next 0/2] net: Prevent RPS table overwrite of active flows

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250729104109.1687418-1-krikku@gmail.com>
Date: Tue, 29 Jul 2025 16:11:07 +0530
From: Krishna Kumar <krikku@...il.com>
To: netdev@...r.kernel.org
Cc: davem@...emloft.net,
	edumazet@...gle.com,
	tom@...bertland.com,
	kuba@...nel.org,
	pabeni@...hat.com,
	horms@...nel.org,
	sdf@...ichev.me,
	kuniyu@...gle.com,
	ahmed.zaki@...el.com,
	aleksander.lobakin@...el.com,
	atenart@...nel.org,
	krishna.ku@...pkart.com,
	krikku@...il.com
Subject: [PATCH v7 net-next 0/2] net: Prevent RPS table overwrite of active flows

This series splits the original RPS patch [1] into two patches for
net-next. It also addresses a kernel test robot warning by defining
rps_flow_is_active() only when aRFS is enabled. I tested v3 with
four builds and reboots: two for [PATCH 1/2] with aRFS enabled &
disabled, and two for [PATCH 2/2]. There are no code changes in v4
and v5, only documentation. Patch v6 has one line change to keep
'hash' field under #ifdef, and was test built with aRFS=on and
aRFS=off. The same two builds were done for v7, along with 15m load
testing with aRFS=on to ensure the new changes are correct.

The first patch prevents RPS table overwrite for active flows thereby
improving aRFS stability.

The second patch caches hash & flow_id in get_rps_cpu() to avoid
recalculating it in set_rps_cpu() (this patch depends on the first).

[1] https://lore.kernel.org/netdev/20250708081516.53048-1-krikku@gmail.com/
[2] https://lore.kernel.org/netdev/20250717064554.3e4d9993@kernel.org/

Signed-off-by: Krishna Kumar <krikku@...il.com>
---
v7: Improve readability of rps_flow_is_active() and remove some
    unnecessary comments.
v6: Keep 'hash' in 'rps_dev_flow' under aRFS config.
v5: Same v4 patch sent with a change in documentation style for "return".
v4: Same v3 patch sent as a new thread instead of a continuation.
v3: Wrapped rps_flow_is_active() in #ifdef CONFIG_RFS_ACCEL to fix
    unused function warning reported by kernel test robot.
v2: Split original patch into two: RPS table overwrite prevention and hash/
    flow_id caching.

Krishna Kumar (2):
  net: Prevent RPS table overwrite of active flows
  net: Cache hash and flow_id to avoid recalculation

 include/net/rps.h    |  7 +++--
 net/core/dev.c       | 71 +++++++++++++++++++++++++++++++++++++-------
 net/core/net-sysfs.c |  4 ++-
 3 files changed, 68 insertions(+), 14 deletions(-)

-- 
2.39.5