[PATCH 4.15 113/146] netfilter: IDLETIMER: be syzkaller friendly

2018-03-13 Thread Greg Kroah-Hartman 
4.15-stable review patch.  If anyone has any objections, please let me know.

--

From: Eric Dumazet 

commit cfc2c740533368b96e2be5e0a4e8c3cace7d9814 upstream.

We had one report from syzkaller [1]

First issue is that INIT_WORK() should be done before mod_timer()
or we risk timer being fired too soon, even with a 1 second timer.

Second issue is that we need to reject too big info->timeout
to avoid overflows in msecs_to_jiffies(info->timeout * 1000), or
risk looping, if result after overflow is 0.

[1]
WARNING: CPU: 1 PID: 5129 at kernel/workqueue.c:1444 __queue_work+0xdf4/0x1230 
kernel/workqueue.c:1444
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 5129 Comm: syzkaller159866 Not tainted 4.16.0-rc1+ #230
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 
01/01/2011
Call Trace:
 
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:53
 panic+0x1e4/0x41c kernel/panic.c:183
 __warn+0x1dc/0x200 kernel/panic.c:547
 report_bug+0x211/0x2d0 lib/bug.c:184
 fixup_bug.part.11+0x37/0x80 arch/x86/kernel/traps.c:178
 fixup_bug arch/x86/kernel/traps.c:247 [inline]
 do_error_trap+0x2d7/0x3e0 arch/x86/kernel/traps.c:296
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:315
 invalid_op+0x22/0x40 arch/x86/entry/entry_64.S:988
RIP: 0010:__queue_work+0xdf4/0x1230 kernel/workqueue.c:1444
RSP: 0018:8801db507538 EFLAGS: 00010006
RAX: 8801aeb46080 RBX: 8801db530200 RCX: 81481404
RDX: 0100 RSI: 86b42640 RDI: 0082
RBP: 8801db507758 R08: 11003b6a0de5 R09: 000c
R10: 8801db5073f0 R11: 0020 R12: 11003b6a0eb6
R13: 8801b1067ae0 R14: 01f8 R15: dc00
 queue_work_on+0x16a/0x1c0 kernel/workqueue.c:1488
 queue_work include/linux/workqueue.h:488 [inline]
 schedule_work include/linux/workqueue.h:546 [inline]
 idletimer_tg_expired+0x44/0x60 net/netfilter/xt_IDLETIMER.c:116
 call_timer_fn+0x228/0x820 kernel/time/timer.c:1326
 expire_timers kernel/time/timer.c:1363 [inline]
 __run_timers+0x7ee/0xb70 kernel/time/timer.c:1666
 run_timer_softirq+0x4c/0x70 kernel/time/timer.c:1692
 __do_softirq+0x2d7/0xb85 kernel/softirq.c:285
 invoke_softirq kernel/softirq.c:365 [inline]
 irq_exit+0x1cc/0x200 kernel/softirq.c:405
 exiting_irq arch/x86/include/asm/apic.h:541 [inline]
 smp_apic_timer_interrupt+0x16b/0x700 arch/x86/kernel/apic/apic.c:1052
 apic_timer_interrupt+0xa9/0xb0 arch/x86/entry/entry_64.S:829
 
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:777 [inline]
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 
[inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x5e/0xba kernel/locking/spinlock.c:184
RSP: 0018:8801c20173c8 EFLAGS: 0282 ORIG_RAX: ff12
RAX: dc00 RBX: 0282 RCX: 0006
RDX: 10d592cd RSI: 110035d68d23 RDI: 0282
RBP: 8801c20173d8 R08: 110038402e47 R09: 
R10:  R11:  R12: 8820e5c8
R13: 8801b1067ad8 R14: 8801aea7c268 R15: 8801aea7c278
 __debug_object_init+0x235/0x1040 lib/debugobjects.c:378
 debug_object_init+0x17/0x20 lib/debugobjects.c:391
 __init_work+0x2b/0x60 kernel/workqueue.c:506
 idletimer_tg_create net/netfilter/xt_IDLETIMER.c:152 [inline]
 idletimer_tg_checkentry+0x691/0xb00 net/netfilter/xt_IDLETIMER.c:213
 xt_check_target+0x22c/0x7d0 net/netfilter/x_tables.c:850
 check_target net/ipv6/netfilter/ip6_tables.c:533 [inline]
 find_check_entry.isra.7+0x935/0xcf0 net/ipv6/netfilter/ip6_tables.c:575
 translate_table+0xf52/0x1690 net/ipv6/netfilter/ip6_tables.c:744
 do_replace net/ipv6/netfilter/ip6_tables.c:1160 [inline]
 do_ip6t_set_ctl+0x370/0x5f0 net/ipv6/netfilter/ip6_tables.c:1686
 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline]
 nf_setsockopt+0x67/0xc0 net/netfilter/nf_sockopt.c:115
 ipv6_setsockopt+0x10b/0x130 net/ipv6/ipv6_sockglue.c:927
 udpv6_setsockopt+0x45/0x80 net/ipv6/udp.c:1422
 sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2976
 SYSC_setsockopt net/socket.c:1850 [inline]
 SyS_setsockopt+0x189/0x360 net/socket.c:1829
 do_syscall_64+0x282/0x940 arch/x86/entry/common.c:287

Fixes: 0902b469bd25 ("netfilter: xtables: idletimer target implementation")
Signed-off-by: Eric Dumazet 
Reported-by: syzkaller 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman 

---
 net/netfilter/xt_IDLETIMER.c |9 ++---
 1 file changed, 6 insertions(+), 3 deletions(-)

--- a/net/netfilter/xt_IDLETIMER.c
+++ b/net/netfilter/xt_IDLETIMER.c
@@ -146,11 +146,11 @@ static int idletimer_tg_create(struct id
timer_setup(>timer->timer, idletimer_tg_expired, 0);
info->timer->refcnt = 1;
 
+   INIT_WORK(>timer->work, idletimer_tg_work);
+
mod_timer(>timer->timer,

[PATCH 4.15 113/146] netfilter: IDLETIMER: be syzkaller friendly

2018-03-13 Thread Greg Kroah-Hartman 
4.15-stable review patch.  If anyone has any objections, please let me know.

--

From: Eric Dumazet 

commit cfc2c740533368b96e2be5e0a4e8c3cace7d9814 upstream.

We had one report from syzkaller [1]

First issue is that INIT_WORK() should be done before mod_timer()
or we risk timer being fired too soon, even with a 1 second timer.

Second issue is that we need to reject too big info->timeout
to avoid overflows in msecs_to_jiffies(info->timeout * 1000), or
risk looping, if result after overflow is 0.

[1]
WARNING: CPU: 1 PID: 5129 at kernel/workqueue.c:1444 __queue_work+0xdf4/0x1230 
kernel/workqueue.c:1444
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 5129 Comm: syzkaller159866 Not tainted 4.16.0-rc1+ #230
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 
01/01/2011
Call Trace:
 
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:53
 panic+0x1e4/0x41c kernel/panic.c:183
 __warn+0x1dc/0x200 kernel/panic.c:547
 report_bug+0x211/0x2d0 lib/bug.c:184
 fixup_bug.part.11+0x37/0x80 arch/x86/kernel/traps.c:178
 fixup_bug arch/x86/kernel/traps.c:247 [inline]
 do_error_trap+0x2d7/0x3e0 arch/x86/kernel/traps.c:296
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:315
 invalid_op+0x22/0x40 arch/x86/entry/entry_64.S:988
RIP: 0010:__queue_work+0xdf4/0x1230 kernel/workqueue.c:1444
RSP: 0018:8801db507538 EFLAGS: 00010006
RAX: 8801aeb46080 RBX: 8801db530200 RCX: 81481404
RDX: 0100 RSI: 86b42640 RDI: 0082
RBP: 8801db507758 R08: 11003b6a0de5 R09: 000c
R10: 8801db5073f0 R11: 0020 R12: 11003b6a0eb6
R13: 8801b1067ae0 R14: 01f8 R15: dc00
 queue_work_on+0x16a/0x1c0 kernel/workqueue.c:1488
 queue_work include/linux/workqueue.h:488 [inline]
 schedule_work include/linux/workqueue.h:546 [inline]
 idletimer_tg_expired+0x44/0x60 net/netfilter/xt_IDLETIMER.c:116
 call_timer_fn+0x228/0x820 kernel/time/timer.c:1326
 expire_timers kernel/time/timer.c:1363 [inline]
 __run_timers+0x7ee/0xb70 kernel/time/timer.c:1666
 run_timer_softirq+0x4c/0x70 kernel/time/timer.c:1692
 __do_softirq+0x2d7/0xb85 kernel/softirq.c:285
 invoke_softirq kernel/softirq.c:365 [inline]
 irq_exit+0x1cc/0x200 kernel/softirq.c:405
 exiting_irq arch/x86/include/asm/apic.h:541 [inline]
 smp_apic_timer_interrupt+0x16b/0x700 arch/x86/kernel/apic/apic.c:1052
 apic_timer_interrupt+0xa9/0xb0 arch/x86/entry/entry_64.S:829
 
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:777 [inline]
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 
[inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x5e/0xba kernel/locking/spinlock.c:184
RSP: 0018:8801c20173c8 EFLAGS: 0282 ORIG_RAX: ff12
RAX: dc00 RBX: 0282 RCX: 0006
RDX: 10d592cd RSI: 110035d68d23 RDI: 0282
RBP: 8801c20173d8 R08: 110038402e47 R09: 
R10:  R11:  R12: 8820e5c8
R13: 8801b1067ad8 R14: 8801aea7c268 R15: 8801aea7c278
 __debug_object_init+0x235/0x1040 lib/debugobjects.c:378
 debug_object_init+0x17/0x20 lib/debugobjects.c:391
 __init_work+0x2b/0x60 kernel/workqueue.c:506
 idletimer_tg_create net/netfilter/xt_IDLETIMER.c:152 [inline]
 idletimer_tg_checkentry+0x691/0xb00 net/netfilter/xt_IDLETIMER.c:213
 xt_check_target+0x22c/0x7d0 net/netfilter/x_tables.c:850
 check_target net/ipv6/netfilter/ip6_tables.c:533 [inline]
 find_check_entry.isra.7+0x935/0xcf0 net/ipv6/netfilter/ip6_tables.c:575
 translate_table+0xf52/0x1690 net/ipv6/netfilter/ip6_tables.c:744
 do_replace net/ipv6/netfilter/ip6_tables.c:1160 [inline]
 do_ip6t_set_ctl+0x370/0x5f0 net/ipv6/netfilter/ip6_tables.c:1686
 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline]
 nf_setsockopt+0x67/0xc0 net/netfilter/nf_sockopt.c:115
 ipv6_setsockopt+0x10b/0x130 net/ipv6/ipv6_sockglue.c:927
 udpv6_setsockopt+0x45/0x80 net/ipv6/udp.c:1422
 sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2976
 SYSC_setsockopt net/socket.c:1850 [inline]
 SyS_setsockopt+0x189/0x360 net/socket.c:1829
 do_syscall_64+0x282/0x940 arch/x86/entry/common.c:287

Fixes: 0902b469bd25 ("netfilter: xtables: idletimer target implementation")
Signed-off-by: Eric Dumazet 
Reported-by: syzkaller 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman 

---
 net/netfilter/xt_IDLETIMER.c |9 ++---
 1 file changed, 6 insertions(+), 3 deletions(-)

--- a/net/netfilter/xt_IDLETIMER.c
+++ b/net/netfilter/xt_IDLETIMER.c
@@ -146,11 +146,11 @@ static int idletimer_tg_create(struct id
timer_setup(>timer->timer, idletimer_tg_expired, 0);
info->timer->refcnt = 1;
 
+   INIT_WORK(>timer->work, idletimer_tg_work);
+
mod_timer(>timer->timer,
  msecs_to_jiffies(info->timeout * 1000) + jiffies);
 
-   INIT_WORK(>timer->work, idletimer_tg_work);
-
return 0;