This is a note to let you know that I've just added the patch titled
net: Do not allow negative values for busy_read and busy_poll sysctl interfaces
to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: net-do-not-allow-negative-values-for-busy_read-and-busy_poll-sysctl-interfaces.patch and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From foo@baz Thu Dec 21 10:35:49 CET 2017
From: Alexander Duyck alexander.h.duyck@intel.com Date: Fri, 24 Mar 2017 09:38:03 -0700 Subject: net: Do not allow negative values for busy_read and busy_poll sysctl interfaces
From: Alexander Duyck alexander.h.duyck@intel.com
[ Upstream commit 95f255211396958c718aef8c45e3923b5211ea7b ]
This change basically codifies what I think was already the limitations on the busy_poll and busy_read sysctl interfaces. We weren't checking the lower bounds and as such could input negative values. The behavior when that was used was dependent on the architecture. In order to prevent any issues with that I am just disabling support for values less than 0 since this way we don't have to worry about any odd behaviors.
By limiting the sysctl values this way it also makes it consistent with how we handle the SO_BUSY_POLL socket option since the value appears to be reported as a signed integer value and negative values are rejected.
Signed-off-by: Alexander Duyck alexander.h.duyck@intel.com Acked-by: Eric Dumazet edumazet@google.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin alexander.levin@verizon.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/core/sysctl_net_core.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
--- a/net/core/sysctl_net_core.c +++ b/net/core/sysctl_net_core.c @@ -360,14 +360,16 @@ static struct ctl_table net_core_table[] .data = &sysctl_net_busy_poll, .maxlen = sizeof(unsigned int), .mode = 0644, - .proc_handler = proc_dointvec + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, }, { .procname = "busy_read", .data = &sysctl_net_busy_read, .maxlen = sizeof(unsigned int), .mode = 0644, - .proc_handler = proc_dointvec + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, }, #endif #ifdef CONFIG_NET_SCHED
Patches currently in stable-queue which might be from alexander.h.duyck@intel.com are
queue-4.4/i40e-do-not-enable-napi-on-q_vectors-that-have-no-rings.patch queue-4.4/net-do-not-allow-negative-values-for-busy_read-and-busy_poll-sysctl-interfaces.patch