net/sched: act_gate: fix configuration of the periodic timer

assigning a dummy value of 'clock_id' to avoid cancellation of the cycle
timer before its initialization was a temporary solution, and we still
need to handle the case where act_gate timer parameters are changed by
commands like the following one:

 # tc action replace action gate <parameters>

the fix consists in the following items:

1) remove the workaround assignment of 'clock_id', and init the list of
   entries before the first error path after IDR atomic check/allocation
2) validate 'clock_id' earlier: there is no need to do IDR atomic
   check/allocation if we know that 'clock_id' is a bad value
3) use a dedicated function, 'gate_setup_timer()', to ensure that the
   timer is cancelled and re-initialized on action overwrite, and also
   ensure we initialize the timer in the error path of tcf_gate_init()

v3: improve comment in the error path of tcf_gate_init() (thanks to
    Vladimir Oltean)
v2: avoid 'goto' in gate_setup_timer (thanks to Cong Wang)

CC: Ivan Vecera <ivecera@redhat.com>
Fixes: a01c245438 ("net/sched: fix a couple of splats in the error path of tfc_gate_init()")
Fixes: a51c328df3 ("net: qos: introduce a gate control flow action")
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Acked-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Davide Caratti 2020-06-16 22:25:21 +02:00 committed by David S. Miller
parent 7024339a1c
commit c362a06e96
1 changed files with 55 additions and 35 deletions

View File

@ -272,6 +272,27 @@ release_list:
return err;
}
static void gate_setup_timer(struct tcf_gate *gact, u64 basetime,
enum tk_offsets tko, s32 clockid,
bool do_init)
{
if (!do_init) {
if (basetime == gact->param.tcfg_basetime &&
tko == gact->tk_offset &&
clockid == gact->param.tcfg_clockid)
return;
spin_unlock_bh(&gact->tcf_lock);
hrtimer_cancel(&gact->hitimer);
spin_lock_bh(&gact->tcf_lock);
}
gact->param.tcfg_basetime = basetime;
gact->param.tcfg_clockid = clockid;
gact->tk_offset = tko;
hrtimer_init(&gact->hitimer, clockid, HRTIMER_MODE_ABS_SOFT);
gact->hitimer.function = gate_timer_func;
}
static int tcf_gate_init(struct net *net, struct nlattr *nla,
struct nlattr *est, struct tc_action **a,
int ovr, int bind, bool rtnl_held,
@ -303,6 +324,27 @@ static int tcf_gate_init(struct net *net, struct nlattr *nla,
if (!tb[TCA_GATE_PARMS])
return -EINVAL;
if (tb[TCA_GATE_CLOCKID]) {
clockid = nla_get_s32(tb[TCA_GATE_CLOCKID]);
switch (clockid) {
case CLOCK_REALTIME:
tk_offset = TK_OFFS_REAL;
break;
case CLOCK_MONOTONIC:
tk_offset = TK_OFFS_MAX;
break;
case CLOCK_BOOTTIME:
tk_offset = TK_OFFS_BOOT;
break;
case CLOCK_TAI:
tk_offset = TK_OFFS_TAI;
break;
default:
NL_SET_ERR_MSG(extack, "Invalid 'clockid'");
return -EINVAL;
}
}
parm = nla_data(tb[TCA_GATE_PARMS]);
index = parm->index;
@ -326,10 +368,6 @@ static int tcf_gate_init(struct net *net, struct nlattr *nla,
tcf_idr_release(*a, bind);
return -EEXIST;
}
if (ret == ACT_P_CREATED) {
to_gate(*a)->param.tcfg_clockid = -1;
INIT_LIST_HEAD(&(to_gate(*a)->param.entries));
}
if (tb[TCA_GATE_PRIORITY])
prio = nla_get_s32(tb[TCA_GATE_PRIORITY]);
@ -340,33 +378,14 @@ static int tcf_gate_init(struct net *net, struct nlattr *nla,
if (tb[TCA_GATE_FLAGS])
gflags = nla_get_u32(tb[TCA_GATE_FLAGS]);
if (tb[TCA_GATE_CLOCKID]) {
clockid = nla_get_s32(tb[TCA_GATE_CLOCKID]);
switch (clockid) {
case CLOCK_REALTIME:
tk_offset = TK_OFFS_REAL;
break;
case CLOCK_MONOTONIC:
tk_offset = TK_OFFS_MAX;
break;
case CLOCK_BOOTTIME:
tk_offset = TK_OFFS_BOOT;
break;
case CLOCK_TAI:
tk_offset = TK_OFFS_TAI;
break;
default:
NL_SET_ERR_MSG(extack, "Invalid 'clockid'");
goto release_idr;
}
}
gact = to_gate(*a);
if (ret == ACT_P_CREATED)
INIT_LIST_HEAD(&gact->param.entries);
err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
if (err < 0)
goto release_idr;
gact = to_gate(*a);
spin_lock_bh(&gact->tcf_lock);
p = &gact->param;
@ -397,14 +416,10 @@ static int tcf_gate_init(struct net *net, struct nlattr *nla,
p->tcfg_cycletime_ext =
nla_get_u64(tb[TCA_GATE_CYCLE_TIME_EXT]);
gate_setup_timer(gact, basetime, tk_offset, clockid,
ret == ACT_P_CREATED);
p->tcfg_priority = prio;
p->tcfg_basetime = basetime;
p->tcfg_clockid = clockid;
p->tcfg_flags = gflags;
gact->tk_offset = tk_offset;
hrtimer_init(&gact->hitimer, clockid, HRTIMER_MODE_ABS_SOFT);
gact->hitimer.function = gate_timer_func;
gate_get_start_time(gact, &start);
gact->current_close_time = start;
@ -433,6 +448,13 @@ chain_put:
if (goto_ch)
tcf_chain_put_by_act(goto_ch);
release_idr:
/* action is not inserted in any list: it's safe to init hitimer
* without taking tcf_lock.
*/
if (ret == ACT_P_CREATED)
gate_setup_timer(gact, gact->param.tcfg_basetime,
gact->tk_offset, gact->param.tcfg_clockid,
true);
tcf_idr_release(*a, bind);
return err;
}
@ -443,9 +465,7 @@ static void tcf_gate_cleanup(struct tc_action *a)
struct tcf_gate_params *p;
p = &gact->param;
if (p->tcfg_clockid != -1)
hrtimer_cancel(&gact->hitimer);
hrtimer_cancel(&gact->hitimer);
release_entry_list(&p->entries);
}