From 2692ba61a82203404abd7dd2a027bda962861f74 Mon Sep 17 00:00:00 2001 From: Xi Wang Date: Fri, 16 Dec 2011 12:44:15 +0000 Subject: sctp: fix incorrect overflow check on autoclose Commit 8ffd3208 voids the previous patches f6778aab and 810c0719 for limiting the autoclose value. If userspace passes in -1 on 32-bit platform, the overflow check didn't work and autoclose would be set to 0xffffffff. This patch defines a max_autoclose (in seconds) for limiting the value and exposes it through sysctl, with the following intentions. 1) Avoid overflowing autoclose * HZ. 2) Keep the default autoclose bound consistent across 32- and 64-bit platforms (INT_MAX / HZ in this patch). 3) Keep the autoclose value consistent between setsockopt() and getsockopt() calls. Suggested-by: Vlad Yasevich Signed-off-by: Xi Wang Signed-off-by: David S. Miller --- net/sctp/sysctl.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'net/sctp/sysctl.c') diff --git a/net/sctp/sysctl.c b/net/sctp/sysctl.c index 6b3952961b85..60ffbd067ff7 100644 --- a/net/sctp/sysctl.c +++ b/net/sctp/sysctl.c @@ -53,6 +53,10 @@ static int sack_timer_min = 1; static int sack_timer_max = 500; static int addr_scope_max = 3; /* check sctp_scope_policy_t in include/net/sctp/constants.h for max entries */ static int rwnd_scale_max = 16; +static unsigned long max_autoclose_min = 0; +static unsigned long max_autoclose_max = + (MAX_SCHEDULE_TIMEOUT / HZ > UINT_MAX) + ? UINT_MAX : MAX_SCHEDULE_TIMEOUT / HZ; extern long sysctl_sctp_mem[3]; extern int sysctl_sctp_rmem[3]; @@ -258,6 +262,15 @@ static ctl_table sctp_table[] = { .extra1 = &one, .extra2 = &rwnd_scale_max, }, + { + .procname = "max_autoclose", + .data = &sctp_max_autoclose, + .maxlen = sizeof(unsigned long), + .mode = 0644, + .proc_handler = &proc_doulongvec_minmax, + .extra1 = &max_autoclose_min, + .extra2 = &max_autoclose_max, + }, { /* sentinel */ } }; -- cgit v1.2.3