posix-timers: fix oops in clock_nanosleep() with CLOCK_MONOTONIC_RAW

PATCH In review Hiroshi Shimamoto 2 participants 6 messages Aug 3, 2009 – Aug 4, 2009

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Hiroshi Shimamoto

author

2009-08-03 02:50 UTC #0 lore raw

PATCH 1/1 posix-timers: fix oops in clock_nanosleep() with CLOCK_MONOTONIC_RAW

From: Hiroshi Shimamoto <[email protected]>

Prevent calling do_nanosleep() with clockid CLOCK_MONOTONIC_RAW, it may cause oops, such as NULL pointer dereference.

Signed-off-by Hiroshi Shimamoto <[email protected]>

---
 kernel/posix-timers.c |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

kernel/posix-timers.c +7 -0

index 052ec4d..d089d05 100644
@@ -202,6 +202,12 @@ static int no_timer_create(struct k_itimer *new_timer)
 	return -EOPNOTSUPP;
 }
 
+static int no_nsleep(const clockid_t which_clock, int flags,
+		     struct timespec *tsave, struct timespec __user *rmtp)
+{
+	return -EOPNOTSUPP;
+}
+
 /*
  * Return nonzero if we know a priori this clockid_t value is bogus.
  */

@@ -254,6 +260,7 @@ static __init int init_posix_timers(void)
 		.clock_get = posix_get_monotonic_raw,
 		.clock_set = do_posix_clock_nosettime,
 		.timer_create = no_timer_create,
+		.nsleep = no_nsleep,
 	};
 
 	register_posix_clock(CLOCK_REALTIME, &clock_realtime);

Signature · 1 line

1.6.3.3

Andrew Morton

2009-08-04 07:23 UTC #1 lore raw

Quoted 28 lines · On Mon, 03 Aug 2009 11:48:19 +0900 Hiroshi Shimamoto…

From: Hiroshi Shimamoto <[email protected]>

Prevent calling do_nanosleep() with clockid CLOCK_MONOTONIC_RAW, it may cause oops, such as NULL pointer dereference.

Signed-off-by Hiroshi Shimamoto <[email protected]>

---
 kernel/posix-timers.c |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

kernel/posix-timers.c +6 -0

index 052ec4d..d089d05 100644
@@ -202,6 +202,12 @@ static int no_timer_create(struct k_itimer *new_timer)
 	return -EOPNOTSUPP;
 }
 
+static int no_nsleep(const clockid_t which_clock, int flags,
+		     struct timespec *tsave, struct timespec __user *rmtp)
+{
+	return -EOPNOTSUPP;
+}
+
 /*
  * Return nonzero if we know a priori this clockid_t value is bogus.
  */

kernel/posix-timers.c static __init int init_posix_timers(void) · line 266

Quoted 7 lines

kernel/posix-timers.c +1 -0

@@ -254,6 +260,7 @@ static __init int init_posix_timers(void)
 		.clock_get = posix_get_monotonic_raw,
 		.clock_set = do_posix_clock_nosettime,
 		.timer_create = no_timer_create,
+		.nsleep = no_nsleep,
 	};
 
 	register_posix_clock(CLOCK_REALTIME, &clock_realtime);

Under which circumstances will this oops trigger?

What userspace setup/actions will trigger the oops?

Thanks.

OK, that CLOCK_DISPATCH() thing should be strangled and burnt...

Hiroshi Shimamoto

author

2009-08-04 07:42 UTC #2 lore raw

Quoted 36 lines · Andrew Morton

Quoted 34 lines · On Mon, 03 Aug 2009 11:48:19 +0900 Hiroshi Shimamoto…

From: Hiroshi Shimamoto <[email protected]>

Prevent calling do_nanosleep() with clockid CLOCK_MONOTONIC_RAW, it may cause oops, such as NULL pointer dereference.

Signed-off-by Hiroshi Shimamoto <[email protected]>

---
 kernel/posix-timers.c |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

kernel/posix-timers.c +7 -0

index 052ec4d..d089d05 100644
@@ -202,6 +202,12 @@ static int no_timer_create(struct k_itimer *new_timer)
 	return -EOPNOTSUPP;
 }
 
+static int no_nsleep(const clockid_t which_clock, int flags,
+		     struct timespec *tsave, struct timespec __user *rmtp)
+{
+	return -EOPNOTSUPP;
+}
+
 /*
  * Return nonzero if we know a priori this clockid_t value is bogus.
  */

@@ -254,6 +260,7 @@ static __init int init_posix_timers(void)
 		.clock_get = posix_get_monotonic_raw,
 		.clock_set = do_posix_clock_nosettime,
 		.timer_create = no_timer_create,
+		.nsleep = no_nsleep,
 	};

Quoted 5 lines

kernel/posix-timers.c static __init int init_posix_timers(void) · line 266
Quoted 1 line
kernel/posix-timers.c +0 -0
 	register_posix_clock(CLOCK_REALTIME, &clock_realtime);
Under which circumstances will this oops trigger?
What userspace setup/actions will trigger the oops?

Sorry for the lack of information.
Userspace program is like this;

#include <time.h>

int main(void)

{
	struct timespec ts;

	ts.tv_sec = 1;
	ts.tv_nsec = 0;

	return clock_nanosleep(4, 0, &ts, NULL);
}

and it will cause oops;

BUG: unable to handle kernel NULL pointer dereference at 0000000000000001
IP: [<ffffffff81029eb5>] __ticket_spin_lock+0x9/0x1a
PGD 3dc6c067 PUD 3b519067 PMD 0 
Oops: 0002 [#1] SMP 
last sysfs file: /sys/devices/pci0000:00/0000:00:1c.0/0000:02:00.0/irq
CPU 0 
Modules linked in: sco bnep l2cap bluetooth sunrpc bridge stp llc ipv6 p4_clockmod speedstep_lib freq_table dm_multipath uinput iTCO_wdt iTCO_vendor_support tg3 i2c_i801 snd_intel8x0 snd_ac97_codec ac97_bus ppdev snd_pcm parport_pc snd_timer floppy parport snd soundcore snd_page_alloc pcspkr ata_generic pata_acpi nouveau drm i2c_algo_bit i2c_core [last unloaded: freq_table]
Pid: 20114, comm: a.out Not tainted 2.6.29.6-213.fc11.x86_64 #1 PC-MY32EXZE78SG
RIP: 0010:[<ffffffff81029eb5>]  [<ffffffff81029eb5>] __ticket_spin_lock+0x9/0x1a
RSP: 0018:ffff88003e08bd88  EFLAGS: 00010046
RAX: 0000000000000100 RBX: 0000000000000001 RCX: 0000000000000001
RDX: 000000000000c350 RSI: 0000000000000286 RDI: 0000000000000001
RBP: ffff88003e08bd88 R08: 0000000000000001 R09: 0000003ec680eec0
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000286
R13: ffff88003e08be20 R14: 000000000000c350 R15: 000000000000c350
FS:  00007fb6cd3996f0(0000) GS:ffffffff817b7000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000001 CR3: 000000003a5c0000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process a.out (pid: 20114, threadinfo ffff88003e08a000, task ffff8800399e1700)
Stack:
 ffff88003e08bd98 ffffffff81029f7f ffff88003e08bdb8 ffffffff813ac07c
 ffff880001011178 ffff88003e08be98 ffff88003e08bde8 ffffffff8105f3a1
 ffff88003e08bdd8 ffff88003e08be98 0000000000000001 000000003b9aca00
Call Trace:
 [<ffffffff81029f7f>] default_spin_lock_flags+0x9/0xe
 [<ffffffff813ac07c>] _spin_lock_irqsave+0x32/0x3b
 [<ffffffff8105f3a1>] lock_hrtimer_base+0x2a/0x50
 [<ffffffff8105f527>] __hrtimer_start_range_ns+0x2f/0x238
 [<ffffffff8105f75e>] hrtimer_start_range_ns+0x14/0x16
 [<ffffffff813aac8b>] do_nanosleep+0x4e/0xae
 [<ffffffff8105f813>] hrtimer_nanosleep+0xb3/0x123
 [<ffffffff8105edea>] ? hrtimer_wakeup+0x0/0x26
 [<ffffffff8105b4ed>] sys_clock_nanosleep+0xc9/0xdf
 [<ffffffff8101133a>] system_call_fastpath+0x16/0x1b
Code: 9c 02 81 44 89 c6 48 89 c7 e8 0a fb ff ff eb 0f 0f b7 f6 40 0f b6 ff 48 89 c2 e8 1c fb ff ff c9 c3 90 55 b8 00 01 00 00 48 89 e5 <f0> 66 0f c1 07 38 e0 74 06 f3 90 8a 07 eb f6 c9 c3 55 48 89 e5 
RIP  [<ffffffff81029eb5>] __ticket_spin_lock+0x9/0x1a
 RSP <ffff88003e08bd88>
CR2: 0000000000000001
---[ end trace e83b583836779b24 ]---

thanks,
Hiroshi

Andrew Morton

2009-08-04 07:58 UTC #3 lore raw

Quoted 14 lines · On Tue, 04 Aug 2009 16:41:33 +0900 Hiroshi Shimamoto…

Userspace program is like this;
#include <time.h>
int main(void)
{
	struct timespec ts;

	ts.tv_sec = 1;
	ts.tv_nsec = 0;

	return clock_nanosleep(4, 0, &ts, NULL);
}

Quoted 3 lines

and it will cause oops;

BUG: unable to handle kernel NULL pointer dereference at 0000000000000001

Well that's not very good.

How far back does this go? posix-timers.c hasn't changed in several kernel versions.

Hiroshi Shimamoto

author

2009-08-04 08:08 UTC #4 lore raw

Quoted 16 lines · Andrew Morton

Quoted 14 lines · On Tue, 04 Aug 2009 16:41:33 +0900 Hiroshi Shimamoto…
Userspace program is like this;
#include <time.h>
int main(void)
{
	struct timespec ts;

	ts.tv_sec = 1;
	ts.tv_nsec = 0;

	return clock_nanosleep(4, 0, &ts, NULL);
}

Quoted 8 lines

Quoted 3 lines
and it will cause oops;
BUG: unable to handle kernel NULL pointer dereference at 0000000000000001
Well that's not very good.
How far back does this go? posix-timers.c hasn't changed in several kernel versions.

Not sure the exact version is. I've just noticed it on the latest git and Fedora 11.
I guess after the below commit;
commit 2d42244ae71d6c7b0884b5664cf2eda30fb2ae68

Author: John Stultz <[email protected]>
Date:   Wed Aug 20 16:37:30 2008 -0700

clocksource: introduce CLOCK_MONOTONIC_RAW

thanks,
Hiroshi

tip-bot for Hiroshi Shimamoto

author

2009-08-04 08:22 UTC #5 lore raw

[tip:timers/urgent] posix-timers: Fix oops in clock_nanosleep() with CLOCK_MONOTONIC_RAW

In reply to Hiroshi Shimamoto

Commit-ID:  70d715fd0597f18528f389b5ac59102263067744
Gitweb:     http://git.kernel.org/tip/70d715fd0597f18528f389b5ac59102263067744
Author:     Hiroshi Shimamoto <[email protected]>
AuthorDate: Mon, 3 Aug 2009 11:48:19 +0900
Committer:  Ingo Molnar <[email protected]>
CommitDate: Tue, 4 Aug 2009 10:16:41 +0200

posix-timers: Fix oops in clock_nanosleep() with CLOCK_MONOTONIC_RAW

Prevent calling do_nanosleep() with clockid CLOCK_MONOTONIC_RAW, it may cause oops, such as NULL pointer dereference.

Signed-off-by Hiroshi Shimamoto <[email protected]>

Cc Andrew Morton <[email protected]>

Cc Thomas Gleixner <[email protected]>

Cc John Stultz <[email protected]>

Cc <[email protected]>

LKML-Reference: <[email protected]>

Signed-off-by Ingo Molnar <[email protected]>

---
 kernel/posix-timers.c |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

kernel/posix-timers.c +7 -0

index 052ec4d..d089d05 100644
@@ -202,6 +202,12 @@ static int no_timer_create(struct k_itimer *new_timer)
 	return -EOPNOTSUPP;
 }
 
+static int no_nsleep(const clockid_t which_clock, int flags,
+		     struct timespec *tsave, struct timespec __user *rmtp)
+{
+	return -EOPNOTSUPP;
+}
+
 /*
  * Return nonzero if we know a priori this clockid_t value is bogus.
  */

@@ -254,6 +260,7 @@ static __init int init_posix_timers(void)
 		.clock_get = posix_get_monotonic_raw,
 		.clock_set = do_posix_clock_nosettime,
 		.timer_create = no_timer_create,
+		.nsleep = no_nsleep,
 	};
 
 	register_posix_clock(CLOCK_REALTIME, &clock_realtime);