net: Do not allow negative values for busy_read and busy_poll sysctl interfaces
Subsystems (2)
PATCH 1/1 net: Do not allow negative values for busy_read and busy_poll sysctl interfaces
From: Alexander Duyck <[email protected]>
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.
--- net/core/sysctl_net_core.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
net/core/sysctl_net_core.c +4 -2
@@ -408,14 +408,16 @@ static int proc_do_rss_key(struct ctl_table *table, int write, .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
Quoted 9 lines · Alexander Duyck
From: Alexander Duyck <[email protected]>
This change basically codifies what I think was already the limitations on the
busy_pollandbusy_readsysctl 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.
Quoted 6 lines
By limiting the sysctl values this way it also makes it consistent with how we handle the
SO_BUSY_POLLsocket option since the value appears to be reported as a signed integer value and negative values are rejected.Signed-off-by Alexander Duyck <[email protected]>---
From: Alexander Duyck <[email protected]>
Date: Fri, 24 Mar 2017 09:38:03 -0700
Quoted 9 lines
From: Alexander Duyck <[email protected]>
This change basically codifies what I think was already the limitations on the
busy_pollandbusy_readsysctl 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.
Quoted 5 lines
By limiting the sysctl values this way it also makes it consistent with how we handle the
SO_BUSY_POLLsocket option since the value appears to be reported as a signed integer value and negative values are rejected.Signed-off-by Alexander Duyck <[email protected]>
Applied, thanks.