From: Ben Hutchings <ben@decadent.org.uk>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: akpm@linux-foundation.org, "Tejun Heo" <tj@kernel.org>
Subject: [PATCH 3.2 36/67] libata: fix sff host state machine locking while polling
Date: Tue, 23 Feb 2016 21:42:03 +0000 [thread overview]
Message-ID: <lsq.1456263723.438312547@decadent.org.uk> (raw)
In-Reply-To: <lsq.1456263722.390955919@decadent.org.uk>
3.2.78-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Tejun Heo <tj@kernel.org>
commit 8eee1d3ed5b6fc8e14389567c9a6f53f82bb7224 upstream.
The bulk of ATA host state machine is implemented by
ata_sff_hsm_move(). The function is called from either the interrupt
handler or, if polling, a work item. Unlike from the interrupt path,
the polling path calls the function without holding the host lock and
ata_sff_hsm_move() selectively grabs the lock.
This is completely broken. If an IRQ triggers while polling is in
progress, the two can easily race and end up accessing the hardware
and updating state machine state at the same time. This can put the
state machine in an illegal state and lead to a crash like the
following.
kernel BUG at drivers/ata/libata-sff.c:1302!
invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN
Modules linked in:
CPU: 1 PID: 10679 Comm: syz-executor Not tainted 4.5.0-rc1+ #300
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
task: ffff88002bd00000 ti: ffff88002e048000 task.ti: ffff88002e048000
RIP: 0010:[<ffffffff83a83409>] [<ffffffff83a83409>] ata_sff_hsm_move+0x619/0x1c60
...
Call Trace:
<IRQ>
[<ffffffff83a84c31>] __ata_sff_port_intr+0x1e1/0x3a0 drivers/ata/libata-sff.c:1584
[<ffffffff83a85611>] ata_bmdma_port_intr+0x71/0x400 drivers/ata/libata-sff.c:2877
[< inline >] __ata_sff_interrupt drivers/ata/libata-sff.c:1629
[<ffffffff83a85bf3>] ata_bmdma_interrupt+0x253/0x580 drivers/ata/libata-sff.c:2902
[<ffffffff81479f98>] handle_irq_event_percpu+0x108/0x7e0 kernel/irq/handle.c:157
[<ffffffff8147a717>] handle_irq_event+0xa7/0x140 kernel/irq/handle.c:205
[<ffffffff81484573>] handle_edge_irq+0x1e3/0x8d0 kernel/irq/chip.c:623
[< inline >] generic_handle_irq_desc include/linux/irqdesc.h:146
[<ffffffff811a92bc>] handle_irq+0x10c/0x2a0 arch/x86/kernel/irq_64.c:78
[<ffffffff811a7e4d>] do_IRQ+0x7d/0x1a0 arch/x86/kernel/irq.c:240
[<ffffffff86653d4c>] common_interrupt+0x8c/0x8c arch/x86/entry/entry_64.S:520
<EOI>
[< inline >] rcu_lock_acquire include/linux/rcupdate.h:490
[< inline >] rcu_read_lock include/linux/rcupdate.h:874
[<ffffffff8164b4a1>] filemap_map_pages+0x131/0xba0 mm/filemap.c:2145
[< inline >] do_fault_around mm/memory.c:2943
[< inline >] do_read_fault mm/memory.c:2962
[< inline >] do_fault mm/memory.c:3133
[< inline >] handle_pte_fault mm/memory.c:3308
[< inline >] __handle_mm_fault mm/memory.c:3418
[<ffffffff816efb16>] handle_mm_fault+0x2516/0x49a0 mm/memory.c:3447
[<ffffffff8127dc16>] __do_page_fault+0x376/0x960 arch/x86/mm/fault.c:1238
[<ffffffff8127e358>] trace_do_page_fault+0xe8/0x420 arch/x86/mm/fault.c:1331
[<ffffffff8126f514>] do_async_page_fault+0x14/0xd0 arch/x86/kernel/kvm.c:264
[<ffffffff86655578>] async_page_fault+0x28/0x30 arch/x86/entry/entry_64.S:986
Fix it by ensuring that the polling path is holding the host lock
before entering ata_sff_hsm_move() so that all hardware accesses and
state updates are performed under the host lock.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-and-tested-by: Dmitry Vyukov <dvyukov@google.com>
Link: http://lkml.kernel.org/g/CACT4Y+b_JsOxJu2EZyEf+mOXORc_zid5V1-pLZSroJVxyWdSpw@mail.gmail.com
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/ata/libata-sff.c | 32 +++++++++++---------------------
1 file changed, 11 insertions(+), 21 deletions(-)
--- a/drivers/ata/libata-sff.c
+++ b/drivers/ata/libata-sff.c
@@ -997,12 +997,9 @@ static inline int ata_hsm_ok_in_wq(struc
static void ata_hsm_qc_complete(struct ata_queued_cmd *qc, int in_wq)
{
struct ata_port *ap = qc->ap;
- unsigned long flags;
if (ap->ops->error_handler) {
if (in_wq) {
- spin_lock_irqsave(ap->lock, flags);
-
/* EH might have kicked in while host lock is
* released.
*/
@@ -1014,8 +1011,6 @@ static void ata_hsm_qc_complete(struct a
} else
ata_port_freeze(ap);
}
-
- spin_unlock_irqrestore(ap->lock, flags);
} else {
if (likely(!(qc->err_mask & AC_ERR_HSM)))
ata_qc_complete(qc);
@@ -1024,10 +1019,8 @@ static void ata_hsm_qc_complete(struct a
}
} else {
if (in_wq) {
- spin_lock_irqsave(ap->lock, flags);
ata_sff_irq_on(ap);
ata_qc_complete(qc);
- spin_unlock_irqrestore(ap->lock, flags);
} else
ata_qc_complete(qc);
}
@@ -1048,9 +1041,10 @@ int ata_sff_hsm_move(struct ata_port *ap
{
struct ata_link *link = qc->dev->link;
struct ata_eh_info *ehi = &link->eh_info;
- unsigned long flags = 0;
int poll_next;
+ lockdep_assert_held(ap->lock);
+
WARN_ON_ONCE((qc->flags & ATA_QCFLAG_ACTIVE) == 0);
/* Make sure ata_sff_qc_issue() does not throw things
@@ -1112,14 +1106,6 @@ fsm_start:
}
}
- /* Send the CDB (atapi) or the first data block (ata pio out).
- * During the state transition, interrupt handler shouldn't
- * be invoked before the data transfer is complete and
- * hsm_task_state is changed. Hence, the following locking.
- */
- if (in_wq)
- spin_lock_irqsave(ap->lock, flags);
-
if (qc->tf.protocol == ATA_PROT_PIO) {
/* PIO data out protocol.
* send first data block.
@@ -1135,9 +1121,6 @@ fsm_start:
/* send CDB */
atapi_send_cdb(ap, qc);
- if (in_wq)
- spin_unlock_irqrestore(ap->lock, flags);
-
/* if polling, ata_sff_pio_task() handles the rest.
* otherwise, interrupt handler takes over from here.
*/
@@ -1361,12 +1344,14 @@ static void ata_sff_pio_task(struct work
u8 status;
int poll_next;
+ spin_lock_irq(ap->lock);
+
BUG_ON(ap->sff_pio_task_link == NULL);
/* qc can be NULL if timeout occurred */
qc = ata_qc_from_tag(ap, link->active_tag);
if (!qc) {
ap->sff_pio_task_link = NULL;
- return;
+ goto out_unlock;
}
fsm_start:
@@ -1381,11 +1366,14 @@ fsm_start:
*/
status = ata_sff_busy_wait(ap, ATA_BUSY, 5);
if (status & ATA_BUSY) {
+ spin_unlock_irq(ap->lock);
ata_msleep(ap, 2);
+ spin_lock_irq(ap->lock);
+
status = ata_sff_busy_wait(ap, ATA_BUSY, 10);
if (status & ATA_BUSY) {
ata_sff_queue_pio_task(link, ATA_SHORT_PAUSE);
- return;
+ goto out_unlock;
}
}
@@ -1402,6 +1390,8 @@ fsm_start:
*/
if (poll_next)
goto fsm_start;
+out_unlock:
+ spin_unlock_irq(ap->lock);
}
/**
next prev parent reply other threads:[~2016-02-23 21:55 UTC|newest]
Thread overview: 74+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-02-23 21:42 [PATCH 3.2 00/67] 3.2.78-rc1 review Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 40/67] Revert "xhci: don't finish a TD if we get a short-transfer event mid TD" Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 54/67] ARM: 8517/1: ICST: avoid arithmetic overflow in icst_hz() Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 51/67] klist: fix starting point removed bug in klist iterators Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 48/67] ocfs2/dlm: clear refmap bit of recovery lock while doing local recovery cleanup Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 45/67] [media] saa7134-alsa: Only frees registered sound cards Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 31/67] ALSA: seq: Fix race at closing in virmidi driver Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 10/67] sctp: allow setting SCTP_SACK_IMMEDIATELY by the application Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 09/67] pptp: fix illegal memory access caused by multiple bind()s Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 64/67] pipe: limit the per-user amount of pages allocated in pipes Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 42/67] xhci: Fix list corruption in urb dequeue at host removal Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 38/67] ALSA: rawmidi: Fix race at copying & updating the position Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 08/67] af_unix: fix struct pid memory leak Ben Hutchings
2016-02-23 22:07 ` Rainer Weikusat
2016-02-24 21:24 ` Ben Hutchings
2016-02-25 7:26 ` Willy Tarreau
2016-02-23 21:42 ` [PATCH 3.2 06/67] usb: cdc-acm: send zero packet for intel 7260 modem Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 05/67] itimers: Handle relative timers with CONFIG_TIME_LOW_RES proper Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 66/67] pipe: Fix buffer offset after partially failed read Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 02/67] hrtimer: Handle remaining time proper for TIME_LOW_RES Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 16/67] ALSA: seq: Degrade the error message for too many opens Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 55/67] sctp: translate network order to host order when users get a hmacid Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 14/67] USB: serial: option: Adding support for Telit LE922 Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 52/67] ALSA: dummy: Implement timer backend switching more safely Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 63/67] unix: correctly track in-flight fds in sending process user_struct Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 01/67] KVM: vmx: fix MPX detection Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 53/67] ALSA: timer: Fix wrong instance passed to slave callbacks Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 34/67] ALSA: seq: Fix yet another races among ALSA timer accesses Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 30/67] intel_scu_ipcutil: underflow in scu_reg_access() Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 43/67] [media] tda1004x: only update the frontend properties if locked Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 62/67] unix: properly account for FDs passed over unix sockets Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 29/67] crypto: algif_hash - wait for crypto_ahash_init() to complete Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 50/67] crypto: algif_skcipher - Do not dereference ctx without socket lock Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 44/67] ALSA: timer: Fix leftover link at closing Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 47/67] mm, vmstat: fix wrong WQ sleep when memory reclaim doesn't make any progress Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 35/67] ALSA: timer: Fix link corruption due to double start or stop Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 11/67] USB: cp210x: add ID for IAI USB to RS485 adaptor Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 15/67] ALSA: seq: Fix incorrect sanity check at snd_seq_oss_synth_cleanup() Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 25/67] crypto: shash - Fix has_key setting Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 61/67] ALSA: usb-audio: avoid freeing umidi object twice Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 03/67] timerfd: Handle relative timers with CONFIG_TIME_LOW_RES proper Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 13/67] USB: serial: visor: fix crash on detecting device without write_urbs Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 20/67] virtio_pci: fix use after free on release Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 18/67] PCI/AER: Flush workqueue on device remove to avoid use-after-free Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 26/67] ALSA: dummy: Disable switching timer backend via sysfs Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 04/67] posix-timers: Handle relative timers with CONFIG_TIME_LOW_RES proper Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 32/67] ALSA: rawmidi: Remove kernel WARNING for NULL user-space buffer check Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 46/67] scsi_dh_rdac: always retry MODE SELECT on command lock violation Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 24/67] tty: Fix unsafe ldisc reference via ioctl(TIOCGETD) Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 28/67] x86/mm/pat: Avoid truncation when converting cpa->numpages to address Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 27/67] drm/vmwgfx: respect 'nomodeset' Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 07/67] cdc-acm:exclude Samsung phone 04e8:685d Ben Hutchings
2016-02-23 21:42 ` Ben Hutchings [this message]
2016-02-23 21:42 ` [PATCH 3.2 56/67] ALSA: timer: Fix race between stop and interrupt Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 12/67] USB: visor: fix null-deref at probe Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 17/67] USB: serial: ftdi_sio: add support for Yaesu SCU-18 cable Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 58/67] ahci: Intel DNV device IDs SATA Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 33/67] ALSA: pcm: Fix potential deadlock in OSS emulation Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 23/67] SCSI: fix crashes in sd and sr runtime PM Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 57/67] ALSA: timer: Fix race at concurrent reads Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 19/67] libata: disable forced PORTS_IMPL for >= AHCI 1.3 Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 39/67] ALSA: seq: Fix lockdep warnings due to double mutex locks Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 60/67] btrfs: properly set the termination value of ctx->pos in readdir Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 67/67] sched: fix __sched_setscheduler() vs load balancing race Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 59/67] ARM: 8519/1: ICST: try other dividends than 1 Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 21/67] rfkill: fix rfkill_fop_read wait_event usage Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 49/67] crypto: user - lock crypto_alg_list on alg dump Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 22/67] perf annotate browser: Fix behaviour of Shift-Tab with nothing focussed Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 41/67] usb: xhci: apply XHCI_PME_STUCK_QUIRK to Intel Broxton-M platforms Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 65/67] iw_cxgb3: Fix incorrectly returning error on success Ben Hutchings
2016-02-23 21:42 ` [PATCH 3.2 37/67] ALSA: rawmidi: Make snd_rawmidi_transmit() race-free Ben Hutchings
2016-02-24 0:48 ` [PATCH 3.2 00/67] 3.2.78-rc1 review Ben Hutchings
2016-02-24 2:48 ` Guenter Roeck
2016-02-24 14:41 ` Ben Hutchings
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