This is a note to let you know that I've just added the patch titled
ALSA: seq: Fix OSS sysex delivery in OSS emulation
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
alsa-seq-fix-oss-sysex-delivery-in-oss-emulation.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 132d358b183ac6ad8b3fea32ad5e0663456d18d1 Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai(a)suse.de>
Date: Tue, 7 Nov 2017 16:05:24 +0100
Subject: ALSA: seq: Fix OSS sysex delivery in OSS emulation
From: Takashi Iwai <tiwai(a)suse.de>
commit 132d358b183ac6ad8b3fea32ad5e0663456d18d1 upstream.
The SYSEX event delivery in OSS sequencer emulation assumed that the
event is encoded in the variable-length data with the straight
buffering. This was the normal behavior in the past, but during the
development, the chained buffers were introduced for carrying more
data, while the OSS code was left intact. As a result, when a SYSEX
event with the chained buffer data is passed to OSS sequencer port,
it may end up with the wrong memory access, as if it were having a too
large buffer.
This patch addresses the bug, by applying the buffer data expansion by
the generic snd_seq_dump_var_event() helper function.
Reported-by: syzbot <syzkaller(a)googlegroups.com>
Reported-by: Mark Salyzyn <salyzyn(a)android.com>
Signed-off-by: Takashi Iwai <tiwai(a)suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
sound/core/seq/oss/seq_oss_midi.c | 4 +---
sound/core/seq/oss/seq_oss_readq.c | 29 +++++++++++++++++++++++++++++
sound/core/seq/oss/seq_oss_readq.h | 2 ++
3 files changed, 32 insertions(+), 3 deletions(-)
--- a/sound/core/seq/oss/seq_oss_midi.c
+++ b/sound/core/seq/oss/seq_oss_midi.c
@@ -612,9 +612,7 @@ send_midi_event(struct seq_oss_devinfo *
if (!dp->timer->running)
len = snd_seq_oss_timer_start(dp->timer);
if (ev->type == SNDRV_SEQ_EVENT_SYSEX) {
- if ((ev->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) == SNDRV_SEQ_EVENT_LENGTH_VARIABLE)
- snd_seq_oss_readq_puts(dp->readq, mdev->seq_device,
- ev->data.ext.ptr, ev->data.ext.len);
+ snd_seq_oss_readq_sysex(dp->readq, mdev->seq_device, ev);
} else {
len = snd_midi_event_decode(mdev->coder, msg, sizeof(msg), ev);
if (len > 0)
--- a/sound/core/seq/oss/seq_oss_readq.c
+++ b/sound/core/seq/oss/seq_oss_readq.c
@@ -118,6 +118,35 @@ snd_seq_oss_readq_puts(struct seq_oss_re
}
/*
+ * put MIDI sysex bytes; the event buffer may be chained, thus it has
+ * to be expanded via snd_seq_dump_var_event().
+ */
+struct readq_sysex_ctx {
+ struct seq_oss_readq *readq;
+ int dev;
+};
+
+static int readq_dump_sysex(void *ptr, void *buf, int count)
+{
+ struct readq_sysex_ctx *ctx = ptr;
+
+ return snd_seq_oss_readq_puts(ctx->readq, ctx->dev, buf, count);
+}
+
+int snd_seq_oss_readq_sysex(struct seq_oss_readq *q, int dev,
+ struct snd_seq_event *ev)
+{
+ struct readq_sysex_ctx ctx = {
+ .readq = q,
+ .dev = dev
+ };
+
+ if ((ev->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) != SNDRV_SEQ_EVENT_LENGTH_VARIABLE)
+ return 0;
+ return snd_seq_dump_var_event(ev, readq_dump_sysex, &ctx);
+}
+
+/*
* copy an event to input queue:
* return zero if enqueued
*/
--- a/sound/core/seq/oss/seq_oss_readq.h
+++ b/sound/core/seq/oss/seq_oss_readq.h
@@ -44,6 +44,8 @@ void snd_seq_oss_readq_delete(struct seq
void snd_seq_oss_readq_clear(struct seq_oss_readq *readq);
unsigned int snd_seq_oss_readq_poll(struct seq_oss_readq *readq, struct file *file, poll_table *wait);
int snd_seq_oss_readq_puts(struct seq_oss_readq *readq, int dev, unsigned char *data, int len);
+int snd_seq_oss_readq_sysex(struct seq_oss_readq *q, int dev,
+ struct snd_seq_event *ev);
int snd_seq_oss_readq_put_event(struct seq_oss_readq *readq, union evrec *ev);
int snd_seq_oss_readq_put_timestamp(struct seq_oss_readq *readq, unsigned long curt, int seq_mode);
int snd_seq_oss_readq_pick(struct seq_oss_readq *q, union evrec *rec);
Patches currently in stable-queue which might be from tiwai(a)suse.de are
queue-4.9/alsa-seq-avoid-invalid-lockdep-class-warning.patch
queue-4.9/alsa-seq-fix-oss-sysex-delivery-in-oss-emulation.patch
This is a note to let you know that I've just added the patch titled
ARM: 8720/1: ensure dump_instr() checks addr_limit
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
arm-8720-1-ensure-dump_instr-checks-addr_limit.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From b9dd05c7002ee0ca8b676428b2268c26399b5e31 Mon Sep 17 00:00:00 2001
From: Mark Rutland <mark.rutland(a)arm.com>
Date: Thu, 2 Nov 2017 18:44:28 +0100
Subject: ARM: 8720/1: ensure dump_instr() checks addr_limit
From: Mark Rutland <mark.rutland(a)arm.com>
commit b9dd05c7002ee0ca8b676428b2268c26399b5e31 upstream.
When CONFIG_DEBUG_USER is enabled, it's possible for a user to
deliberately trigger dump_instr() with a chosen kernel address.
Let's avoid problems resulting from this by using get_user() rather than
__get_user(), ensuring that we don't erroneously access kernel memory.
So that we can use the same code to dump user instructions and kernel
instructions, the common dumping code is factored out to __dump_instr(),
with the fs manipulated appropriately in dump_instr() around calls to
this.
Signed-off-by: Mark Rutland <mark.rutland(a)arm.com>
Signed-off-by: Russell King <rmk+kernel(a)armlinux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
arch/arm/kernel/traps.c | 28 ++++++++++++++++++----------
1 file changed, 18 insertions(+), 10 deletions(-)
--- a/arch/arm/kernel/traps.c
+++ b/arch/arm/kernel/traps.c
@@ -152,30 +152,26 @@ static void dump_mem(const char *lvl, co
set_fs(fs);
}
-static void dump_instr(const char *lvl, struct pt_regs *regs)
+static void __dump_instr(const char *lvl, struct pt_regs *regs)
{
unsigned long addr = instruction_pointer(regs);
const int thumb = thumb_mode(regs);
const int width = thumb ? 4 : 8;
- mm_segment_t fs;
char str[sizeof("00000000 ") * 5 + 2 + 1], *p = str;
int i;
/*
- * We need to switch to kernel mode so that we can use __get_user
- * to safely read from kernel space. Note that we now dump the
- * code first, just in case the backtrace kills us.
+ * Note that we now dump the code first, just in case the backtrace
+ * kills us.
*/
- fs = get_fs();
- set_fs(KERNEL_DS);
for (i = -4; i < 1 + !!thumb; i++) {
unsigned int val, bad;
if (thumb)
- bad = __get_user(val, &((u16 *)addr)[i]);
+ bad = get_user(val, &((u16 *)addr)[i]);
else
- bad = __get_user(val, &((u32 *)addr)[i]);
+ bad = get_user(val, &((u32 *)addr)[i]);
if (!bad)
p += sprintf(p, i == 0 ? "(%0*x) " : "%0*x ",
@@ -186,8 +182,20 @@ static void dump_instr(const char *lvl,
}
}
printk("%sCode: %s\n", lvl, str);
+}
- set_fs(fs);
+static void dump_instr(const char *lvl, struct pt_regs *regs)
+{
+ mm_segment_t fs;
+
+ if (!user_mode(regs)) {
+ fs = get_fs();
+ set_fs(KERNEL_DS);
+ __dump_instr(lvl, regs);
+ set_fs(fs);
+ } else {
+ __dump_instr(lvl, regs);
+ }
}
#ifdef CONFIG_ARM_UNWIND
Patches currently in stable-queue which might be from mark.rutland(a)arm.com are
queue-4.9/arm-8720-1-ensure-dump_instr-checks-addr_limit.patch
This is a note to let you know that I've just added the patch titled
ALSA: seq: Avoid invalid lockdep class warning
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
alsa-seq-avoid-invalid-lockdep-class-warning.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 3510c7aa069aa83a2de6dab2b41401a198317bdc Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai(a)suse.de>
Date: Mon, 6 Nov 2017 20:16:50 +0100
Subject: ALSA: seq: Avoid invalid lockdep class warning
From: Takashi Iwai <tiwai(a)suse.de>
commit 3510c7aa069aa83a2de6dab2b41401a198317bdc upstream.
The recent fix for adding rwsem nesting annotation was using the given
"hop" argument as the lock subclass key. Although the idea itself
works, it may trigger a kernel warning like:
BUG: looking up invalid subclass: 8
....
since the lockdep has a smaller number of subclasses (8) than we
currently allow for the hops there (10).
The current definition is merely a sanity check for avoiding the too
deep delivery paths, and the 8 hops are already enough. So, as a
quick fix, just follow the max hops as same as the max lockdep
subclasses.
Fixes: 1f20f9ff57ca ("ALSA: seq: Fix nested rwsem annotation for lockdep splat")
Reported-by: syzbot <syzkaller(a)googlegroups.com>
Signed-off-by: Takashi Iwai <tiwai(a)suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
include/sound/seq_kernel.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/include/sound/seq_kernel.h
+++ b/include/sound/seq_kernel.h
@@ -49,7 +49,8 @@ typedef union snd_seq_timestamp snd_seq_
#define SNDRV_SEQ_DEFAULT_CLIENT_EVENTS 200
/* max delivery path length */
-#define SNDRV_SEQ_MAX_HOPS 10
+/* NOTE: this shouldn't be greater than MAX_LOCKDEP_SUBCLASSES */
+#define SNDRV_SEQ_MAX_HOPS 8
/* max size of event size */
#define SNDRV_SEQ_MAX_EVENT_LEN 0x3fffffff
Patches currently in stable-queue which might be from tiwai(a)suse.de are
queue-4.9/alsa-seq-avoid-invalid-lockdep-class-warning.patch
queue-4.9/alsa-seq-fix-oss-sysex-delivery-in-oss-emulation.patch
This is a note to let you know that I've just added the patch titled
x86/uaccess, sched/preempt: Verify access_ok() context
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
x86-uaccess-sched-preempt-verify-access_ok-context.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 7c4788950ba5922fde976d80b72baf46f14dee8d Mon Sep 17 00:00:00 2001
From: Peter Zijlstra <peterz(a)infradead.org>
Date: Tue, 22 Nov 2016 10:57:15 +0100
Subject: x86/uaccess, sched/preempt: Verify access_ok() context
From: Peter Zijlstra <peterz(a)infradead.org>
commit 7c4788950ba5922fde976d80b72baf46f14dee8d upstream.
I recently encountered wreckage because access_ok() was used where it
should not be, add an explicit WARN when access_ok() is used wrongly.
Signed-off-by: Peter Zijlstra (Intel) <peterz(a)infradead.org>
Cc: Andy Lutomirski <luto(a)amacapital.net>
Cc: H. Peter Anvin <hpa(a)zytor.com>
Cc: Linus Torvalds <torvalds(a)linux-foundation.org>
Cc: Peter Zijlstra <peterz(a)infradead.org>
Cc: Thomas Gleixner <tglx(a)linutronix.de>
Cc: linux-kernel(a)vger.kernel.org
Signed-off-by: Ingo Molnar <mingo(a)kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
arch/x86/include/asm/uaccess.h | 13 +++++++++++--
include/linux/preempt.h | 21 +++++++++++++--------
2 files changed, 24 insertions(+), 10 deletions(-)
--- a/arch/x86/include/asm/uaccess.h
+++ b/arch/x86/include/asm/uaccess.h
@@ -66,6 +66,12 @@ static inline bool __chk_range_not_ok(un
__chk_range_not_ok((unsigned long __force)(addr), size, limit); \
})
+#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
+# define WARN_ON_IN_IRQ() WARN_ON_ONCE(!in_task())
+#else
+# define WARN_ON_IN_IRQ()
+#endif
+
/**
* access_ok: - Checks if a user space pointer is valid
* @type: Type of access: %VERIFY_READ or %VERIFY_WRITE. Note that
@@ -86,8 +92,11 @@ static inline bool __chk_range_not_ok(un
* checks that the pointer is in the user space range - after calling
* this function, memory access functions may still return -EFAULT.
*/
-#define access_ok(type, addr, size) \
- likely(!__range_not_ok(addr, size, user_addr_max()))
+#define access_ok(type, addr, size) \
+({ \
+ WARN_ON_IN_IRQ(); \
+ likely(!__range_not_ok(addr, size, user_addr_max())); \
+})
/*
* The exception table consists of pairs of addresses relative to the
--- a/include/linux/preempt.h
+++ b/include/linux/preempt.h
@@ -65,19 +65,24 @@
/*
* Are we doing bottom half or hardware interrupt processing?
- * Are we in a softirq context? Interrupt context?
- * in_softirq - Are we currently processing softirq or have bh disabled?
- * in_serving_softirq - Are we currently processing softirq?
+ *
+ * in_irq() - We're in (hard) IRQ context
+ * in_softirq() - We have BH disabled, or are processing softirqs
+ * in_interrupt() - We're in NMI,IRQ,SoftIRQ context or have BH disabled
+ * in_serving_softirq() - We're in softirq context
+ * in_nmi() - We're in NMI context
+ * in_task() - We're in task context
+ *
+ * Note: due to the BH disabled confusion: in_softirq(),in_interrupt() really
+ * should not be used in new code.
*/
#define in_irq() (hardirq_count())
#define in_softirq() (softirq_count())
#define in_interrupt() (irq_count())
#define in_serving_softirq() (softirq_count() & SOFTIRQ_OFFSET)
-
-/*
- * Are we in NMI context?
- */
-#define in_nmi() (preempt_count() & NMI_MASK)
+#define in_nmi() (preempt_count() & NMI_MASK)
+#define in_task() (!(preempt_count() & \
+ (NMI_MASK | HARDIRQ_MASK | SOFTIRQ_OFFSET)))
/*
* The preempt_count offset after preempt_disable();
Patches currently in stable-queue which might be from peterz(a)infradead.org are
queue-4.4/x86-uaccess-sched-preempt-verify-access_ok-context.patch
This is a note to let you know that I've just added the patch titled
platform/x86: hp-wmi: Fix error value for hp_wmi_tablet_state
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
platform-x86-hp-wmi-fix-error-value-for-hp_wmi_tablet_state.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From c7dfc2facbd69dad89b75e13c608da709668dcd0 Mon Sep 17 00:00:00 2001
From: Carlo Caione <carlo(a)endlessm.com>
Date: Sun, 9 Apr 2017 15:56:07 +0200
Subject: platform/x86: hp-wmi: Fix error value for hp_wmi_tablet_state
From: Carlo Caione <carlo(a)endlessm.com>
commit c7dfc2facbd69dad89b75e13c608da709668dcd0 upstream.
hp_wmi_tablet_state() fails to return the correct error code when
hp_wmi_perform_query() returns the HP WMI query specific error code
that is a positive value.
Signed-off-by: Carlo Caione <carlo(a)endlessm.com>
Signed-off-by: Darren Hart (VMware) <dvhart(a)infradead.org>
Cc: Philip Müller <philm(a)manjaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/platform/x86/hp-wmi.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/platform/x86/hp-wmi.c
+++ b/drivers/platform/x86/hp-wmi.c
@@ -291,7 +291,7 @@ static int hp_wmi_tablet_state(void)
int ret = hp_wmi_perform_query(HPWMI_HARDWARE_QUERY, 0, &state,
sizeof(state), sizeof(state));
if (ret)
- return ret;
+ return -EINVAL;
return (state & 0x4) ? 1 : 0;
}
Patches currently in stable-queue which might be from carlo(a)endlessm.com are
queue-4.4/platform-x86-hp-wmi-do-not-shadow-error-values.patch
queue-4.4/platform-x86-hp-wmi-fix-detection-for-dock-and-tablet-mode.patch
queue-4.4/platform-x86-hp-wmi-fix-error-value-for-hp_wmi_tablet_state.patch
This is a note to let you know that I've just added the patch titled
platform/x86: hp-wmi: Do not shadow error values
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
platform-x86-hp-wmi-do-not-shadow-error-values.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From d313876925f3e7a480a02773fd333bcab9202d5e Mon Sep 17 00:00:00 2001
From: Carlo Caione <carlo(a)endlessm.com>
Date: Wed, 19 Apr 2017 22:36:39 +0200
Subject: platform/x86: hp-wmi: Do not shadow error values
From: Carlo Caione <carlo(a)endlessm.com>
commit d313876925f3e7a480a02773fd333bcab9202d5e upstream.
All the helper functions (i.e. hp_wmi_dock_state, hp_wmi_tablet_state,
...) using hp_wmi_perform_query to perform an HP WMI query shadow the
returned value in case of error.
We return -EINVAL only when the HP WMI query returns a positive value
(the specific error code) to not mix this up with the actual value
returned by the helper function.
Suggested-by: Andy Shevchenko <andriy.shevchenko(a)linux.intel.com>
Signed-off-by: Carlo Caione <carlo(a)endlessm.com>
Signed-off-by: Darren Hart (VMware) <dvhart(a)infradead.org>
Cc: Philip Müller <philm(a)manjaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
drivers/platform/x86/hp-wmi.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)
--- a/drivers/platform/x86/hp-wmi.c
+++ b/drivers/platform/x86/hp-wmi.c
@@ -249,7 +249,7 @@ static int hp_wmi_display_state(void)
int ret = hp_wmi_perform_query(HPWMI_DISPLAY_QUERY, 0, &state,
sizeof(state), sizeof(state));
if (ret)
- return -EINVAL;
+ return ret < 0 ? ret : -EINVAL;
return state;
}
@@ -259,7 +259,7 @@ static int hp_wmi_hddtemp_state(void)
int ret = hp_wmi_perform_query(HPWMI_HDDTEMP_QUERY, 0, &state,
sizeof(state), sizeof(state));
if (ret)
- return -EINVAL;
+ return ret < 0 ? ret : -EINVAL;
return state;
}
@@ -269,7 +269,7 @@ static int hp_wmi_als_state(void)
int ret = hp_wmi_perform_query(HPWMI_ALS_QUERY, 0, &state,
sizeof(state), sizeof(state));
if (ret)
- return -EINVAL;
+ return ret < 0 ? ret : -EINVAL;
return state;
}
@@ -280,7 +280,7 @@ static int hp_wmi_dock_state(void)
sizeof(state), sizeof(state));
if (ret)
- return -EINVAL;
+ return ret < 0 ? ret : -EINVAL;
return state & 0x1;
}
@@ -291,7 +291,7 @@ static int hp_wmi_tablet_state(void)
int ret = hp_wmi_perform_query(HPWMI_HARDWARE_QUERY, 0, &state,
sizeof(state), sizeof(state));
if (ret)
- return -EINVAL;
+ return ret < 0 ? ret : -EINVAL;
return (state & 0x4) ? 1 : 0;
}
@@ -324,7 +324,7 @@ static int __init hp_wmi_enable_hotkeys(
int ret = hp_wmi_perform_query(HPWMI_BIOS_QUERY, 1, &value,
sizeof(value), 0);
if (ret)
- return -EINVAL;
+ return ret < 0 ? ret : -EINVAL;
return 0;
}
@@ -337,7 +337,7 @@ static int hp_wmi_set_block(void *data,
ret = hp_wmi_perform_query(HPWMI_WIRELESS_QUERY, 1,
&query, sizeof(query), 0);
if (ret)
- return -EINVAL;
+ return ret < 0 ? ret : -EINVAL;
return 0;
}
@@ -429,7 +429,7 @@ static int hp_wmi_post_code_state(void)
int ret = hp_wmi_perform_query(HPWMI_POSTCODEERROR_QUERY, 0, &state,
sizeof(state), sizeof(state));
if (ret)
- return -EINVAL;
+ return ret < 0 ? ret : -EINVAL;
return state;
}
@@ -495,7 +495,7 @@ static ssize_t set_als(struct device *de
int ret = hp_wmi_perform_query(HPWMI_ALS_QUERY, 1, &tmp,
sizeof(tmp), sizeof(tmp));
if (ret)
- return -EINVAL;
+ return ret < 0 ? ret : -EINVAL;
return count;
}
@@ -516,7 +516,7 @@ static ssize_t set_postcode(struct devic
ret = hp_wmi_perform_query(HPWMI_POSTCODEERROR_QUERY, 1, &tmp,
sizeof(tmp), sizeof(tmp));
if (ret)
- return -EINVAL;
+ return ret < 0 ? ret : -EINVAL;
return count;
}
Patches currently in stable-queue which might be from carlo(a)endlessm.com are
queue-4.4/platform-x86-hp-wmi-do-not-shadow-error-values.patch
queue-4.4/platform-x86-hp-wmi-fix-detection-for-dock-and-tablet-mode.patch
queue-4.4/platform-x86-hp-wmi-fix-error-value-for-hp_wmi_tablet_state.patch
This is a note to let you know that I've just added the patch titled
workqueue: Fix NULL pointer dereference
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
workqueue-fix-null-pointer-dereference.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From cef572ad9bd7f85035ba8272e5352040e8be0152 Mon Sep 17 00:00:00 2001
From: Li Bin <huawei.libin(a)huawei.com>
Date: Sat, 28 Oct 2017 11:07:28 +0800
Subject: workqueue: Fix NULL pointer dereference
From: Li Bin <huawei.libin(a)huawei.com>
commit cef572ad9bd7f85035ba8272e5352040e8be0152 upstream.
When queue_work() is used in irq (not in task context), there is
a potential case that trigger NULL pointer dereference.
----------------------------------------------------------------
worker_thread()
|-spin_lock_irq()
|-process_one_work()
|-worker->current_pwq = pwq
|-spin_unlock_irq()
|-worker->current_func(work)
|-spin_lock_irq()
|-worker->current_pwq = NULL
|-spin_unlock_irq()
//interrupt here
|-irq_handler
|-__queue_work()
//assuming that the wq is draining
|-is_chained_work(wq)
|-current_wq_worker()
//Here, 'current' is the interrupted worker!
|-current->current_pwq is NULL here!
|-schedule()
----------------------------------------------------------------
Avoid it by checking for task context in current_wq_worker(), and
if not in task context, we shouldn't use the 'current' to check the
condition.
Reported-by: Xiaofei Tan <tanxiaofei(a)huawei.com>
Signed-off-by: Li Bin <huawei.libin(a)huawei.com>
Reviewed-by: Lai Jiangshan <jiangshanlai(a)gmail.com>
Signed-off-by: Tejun Heo <tj(a)kernel.org>
Fixes: 8d03ecfe4718 ("workqueue: reimplement is_chained_work() using current_wq_worker()")
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
kernel/workqueue_internal.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/kernel/workqueue_internal.h
+++ b/kernel/workqueue_internal.h
@@ -9,6 +9,7 @@
#include <linux/workqueue.h>
#include <linux/kthread.h>
+#include <linux/preempt.h>
struct worker_pool;
@@ -59,7 +60,7 @@ struct worker {
*/
static inline struct worker *current_wq_worker(void)
{
- if (current->flags & PF_WQ_WORKER)
+ if (in_task() && (current->flags & PF_WQ_WORKER))
return kthread_data(current);
return NULL;
}
Patches currently in stable-queue which might be from huawei.libin(a)huawei.com are
queue-4.4/workqueue-fix-null-pointer-dereference.patch
This is a note to let you know that I've just added the patch titled
MIPS: SMP: Use a completion event to signal CPU up
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
mips-smp-use-a-completion-event-to-signal-cpu-up.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From a00eeede507c975087b7b8df8cf2c9f88ba285de Mon Sep 17 00:00:00 2001
From: Matt Redfearn <matt.redfearn(a)imgtec.com>
Date: Fri, 4 Nov 2016 09:28:56 +0000
Subject: MIPS: SMP: Use a completion event to signal CPU up
From: Matt Redfearn <matt.redfearn(a)imgtec.com>
commit a00eeede507c975087b7b8df8cf2c9f88ba285de upstream.
If a secondary CPU failed to start, for any reason, the CPU requesting
the secondary to start would get stuck in the loop waiting for the
secondary to be present in the cpu_callin_map.
Rather than that, use a completion event to signal that the secondary
CPU has started and is waiting to synchronise counters.
Since the CPU presence will no longer be marked in cpu_callin_map,
remove the redundant test from arch_cpu_idle_dead().
Signed-off-by: Matt Redfearn <matt.redfearn(a)imgtec.com>
Cc: Maciej W. Rozycki <macro(a)imgtec.com>
Cc: Jiri Slaby <jslaby(a)suse.cz>
Cc: Paul Gortmaker <paul.gortmaker(a)windriver.com>
Cc: Chris Metcalf <cmetcalf(a)mellanox.com>
Cc: Thomas Gleixner <tglx(a)linutronix.de>
Cc: Qais Yousef <qsyousef(a)gmail.com>
Cc: James Hogan <james.hogan(a)imgtec.com>
Cc: Paul Burton <paul.burton(a)imgtec.com>
Cc: Marcin Nowakowski <marcin.nowakowski(a)imgtec.com>
Cc: Andrew Morton <akpm(a)linux-foundation.org>
Cc: linux-mips(a)linux-mips.org
Cc: linux-kernel(a)vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14502/
Signed-off-by: Ralf Baechle <ralf(a)linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
arch/mips/kernel/process.c | 4 +---
arch/mips/kernel/smp.c | 15 +++++++++------
2 files changed, 10 insertions(+), 9 deletions(-)
--- a/arch/mips/kernel/process.c
+++ b/arch/mips/kernel/process.c
@@ -49,9 +49,7 @@
#ifdef CONFIG_HOTPLUG_CPU
void arch_cpu_idle_dead(void)
{
- /* What the heck is this check doing ? */
- if (!cpumask_test_cpu(smp_processor_id(), &cpu_callin_map))
- play_dead();
+ play_dead();
}
#endif
--- a/arch/mips/kernel/smp.c
+++ b/arch/mips/kernel/smp.c
@@ -64,6 +64,8 @@ EXPORT_SYMBOL(cpu_sibling_map);
cpumask_t cpu_core_map[NR_CPUS] __read_mostly;
EXPORT_SYMBOL(cpu_core_map);
+static DECLARE_COMPLETION(cpu_running);
+
/*
* A logcal cpu mask containing only one VPE per core to
* reduce the number of IPIs on large MT systems.
@@ -174,7 +176,7 @@ asmlinkage void start_secondary(void)
cpumask_set_cpu(cpu, &cpu_coherent_mask);
notify_cpu_starting(cpu);
- cpumask_set_cpu(cpu, &cpu_callin_map);
+ complete(&cpu_running);
synchronise_count_slave(cpu);
set_cpu_online(cpu, true);
@@ -242,7 +244,6 @@ void smp_prepare_boot_cpu(void)
{
set_cpu_possible(0, true);
set_cpu_online(0, true);
- cpumask_set_cpu(0, &cpu_callin_map);
}
int __cpu_up(unsigned int cpu, struct task_struct *tidle)
@@ -250,11 +251,13 @@ int __cpu_up(unsigned int cpu, struct ta
mp_ops->boot_secondary(cpu, tidle);
/*
- * Trust is futile. We should really have timeouts ...
+ * We must check for timeout here, as the CPU will not be marked
+ * online until the counters are synchronised.
*/
- while (!cpumask_test_cpu(cpu, &cpu_callin_map)) {
- udelay(100);
- schedule();
+ if (!wait_for_completion_timeout(&cpu_running,
+ msecs_to_jiffies(1000))) {
+ pr_crit("CPU%u: failed to start\n", cpu);
+ return -EIO;
}
synchronise_count_master(cpu);
Patches currently in stable-queue which might be from matt.redfearn(a)imgtec.com are
queue-4.4/mips-smp-fix-deadlock-online-race.patch
queue-4.4/mips-smp-use-a-completion-event-to-signal-cpu-up.patch
This is a note to let you know that I've just added the patch titled
MIPS: SMP: Fix deadlock & online race
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
mips-smp-fix-deadlock-online-race.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 9e8c399a88f0b87e41a894911475ed2a8f8dff9e Mon Sep 17 00:00:00 2001
From: Matt Redfearn <matt.redfearn(a)imgtec.com>
Date: Wed, 27 Sep 2017 10:13:25 +0100
Subject: MIPS: SMP: Fix deadlock & online race
From: Matt Redfearn <matt.redfearn(a)imgtec.com>
commit 9e8c399a88f0b87e41a894911475ed2a8f8dff9e upstream.
Commit 6f542ebeaee0 ("MIPS: Fix race on setting and getting
cpu_online_mask") effectively reverted commit 8f46cca1e6c06 ("MIPS: SMP:
Fix possibility of deadlock when bringing CPUs online") and thus has
reinstated the possibility of deadlock.
The commit was based on testing of kernel v4.4, where the CPU hotplug
core code issued a BUG() if the starting CPU is not marked online when
the boot CPU returns from __cpu_up. The commit fixes this race (in
v4.4), but re-introduces the deadlock situation.
As noted in the commit message, upstream differs in this area. Commit
8df3e07e7f21f ("cpu/hotplug: Let upcoming cpu bring itself fully up")
adds a completion event in the CPU hotplug core code, making this race
impossible. However, people were unhappy with relying on the core code
to do the right thing.
To address the issues both commits were trying to fix, add a second
completion event in the MIPS smp hotplug path. It removes the
possibility of a race, since the MIPS smp hotplug code now synchronises
both the boot and secondary CPUs before they return to the hotplug core
code. It also addresses the deadlock by ensuring that the secondary CPU
is not marked online before it's counters are synchronised.
This fix should also be backported to fix the race condition introduced
by the backport of commit 8f46cca1e6c06 ("MIPS: SMP: Fix possibility of
deadlock when bringing CPUs online"), through really that race only
existed before commit 8df3e07e7f21f ("cpu/hotplug: Let upcoming cpu
bring itself fully up").
Signed-off-by: Matt Redfearn <matt.redfearn(a)imgtec.com>
Fixes: 6f542ebeaee0 ("MIPS: Fix race on setting and getting cpu_online_mask")
CC: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext(a)nokia.com>
Patchwork: https://patchwork.linux-mips.org/patch/17376/
Signed-off-by: James Hogan <jhogan(a)kernel.org>
[jhogan(a)kernel.org: Backported 4.1..4.9]
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
arch/mips/kernel/smp.c | 22 ++++++++++++++++------
1 file changed, 16 insertions(+), 6 deletions(-)
--- a/arch/mips/kernel/smp.c
+++ b/arch/mips/kernel/smp.c
@@ -64,6 +64,7 @@ EXPORT_SYMBOL(cpu_sibling_map);
cpumask_t cpu_core_map[NR_CPUS] __read_mostly;
EXPORT_SYMBOL(cpu_core_map);
+static DECLARE_COMPLETION(cpu_starting);
static DECLARE_COMPLETION(cpu_running);
/*
@@ -176,6 +177,12 @@ asmlinkage void start_secondary(void)
cpumask_set_cpu(cpu, &cpu_coherent_mask);
notify_cpu_starting(cpu);
+ /* Notify boot CPU that we're starting & ready to sync counters */
+ complete(&cpu_starting);
+
+ synchronise_count_slave(cpu);
+
+ /* The CPU is running and counters synchronised, now mark it online */
set_cpu_online(cpu, true);
set_cpu_sibling_map(cpu);
@@ -183,8 +190,11 @@ asmlinkage void start_secondary(void)
calculate_cpu_foreign_map();
+ /*
+ * Notify boot CPU that we're up & online and it can safely return
+ * from __cpu_up
+ */
complete(&cpu_running);
- synchronise_count_slave(cpu);
/*
* irq will be enabled in ->smp_finish(), enabling it too early
@@ -250,17 +260,17 @@ int __cpu_up(unsigned int cpu, struct ta
{
mp_ops->boot_secondary(cpu, tidle);
- /*
- * We must check for timeout here, as the CPU will not be marked
- * online until the counters are synchronised.
- */
- if (!wait_for_completion_timeout(&cpu_running,
+ /* Wait for CPU to start and be ready to sync counters */
+ if (!wait_for_completion_timeout(&cpu_starting,
msecs_to_jiffies(1000))) {
pr_crit("CPU%u: failed to start\n", cpu);
return -EIO;
}
synchronise_count_master(cpu);
+
+ /* Wait for CPU to finish startup & mark itself online before return */
+ wait_for_completion(&cpu_running);
return 0;
}
Patches currently in stable-queue which might be from matt.redfearn(a)imgtec.com are
queue-4.4/mips-smp-fix-deadlock-online-race.patch
queue-4.4/mips-smp-use-a-completion-event-to-signal-cpu-up.patch
This is a note to let you know that I've just added the patch titled
MIPS: Fix race on setting and getting cpu_online_mask
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=sum…
The filename of the patch is:
mips-fix-race-on-setting-and-getting-cpu_online_mask.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable(a)vger.kernel.org> know about it.
>From 6f542ebeaee0ee552a902ce3892220fc22c7ec8e Mon Sep 17 00:00:00 2001
From: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext(a)nokia.com>
Date: Thu, 3 Aug 2017 08:20:22 +0200
Subject: MIPS: Fix race on setting and getting cpu_online_mask
From: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext(a)nokia.com>
commit 6f542ebeaee0ee552a902ce3892220fc22c7ec8e upstream.
While testing cpu hoptlug (cpu down and up in loops) on kernel 4.4, it was
observed that occasionally check for cpu online will fail in kernel/cpu.c,
_cpu_up:
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/tre…
518 /* Arch-specific enabling code. */
519 ret = __cpu_up(cpu, idle);
520
521 if (ret != 0)
522 goto out_notify;
523 BUG_ON(!cpu_online(cpu));
Reason is race between start_secondary and _cpu_up. cpu_callin_map is set
before cpu_online_mask. In __cpu_up, cpu_callin_map is waited for, but cpu
online mask is not, resulting in race in which secondary processor started
and set cpu_callin_map, but not yet set the online mask,resulting in above
BUG being hit.
Upstream differs in the area. cpu_online check is in bringup_wait_for_ap,
which is after cpu reached AP_ONLINE_IDLE,where secondary passed its start
function. Nonetheless, fix makes start_secondary safe and not depending on
other locks throughout the code. It protects as well against cpu_online
checks put in between sometimes in the future.
Fix this by moving completion after all flags are set.
Signed-off-by: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext(a)nokia.com>
Cc: Alexander Sverdlin <alexander.sverdlin(a)nokia.com>
Cc: linux-mips(a)linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16925/
Signed-off-by: Ralf Baechle <ralf(a)linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org>
---
arch/mips/kernel/smp.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
--- a/arch/mips/kernel/smp.c
+++ b/arch/mips/kernel/smp.c
@@ -176,9 +176,6 @@ asmlinkage void start_secondary(void)
cpumask_set_cpu(cpu, &cpu_coherent_mask);
notify_cpu_starting(cpu);
- complete(&cpu_running);
- synchronise_count_slave(cpu);
-
set_cpu_online(cpu, true);
set_cpu_sibling_map(cpu);
@@ -186,6 +183,9 @@ asmlinkage void start_secondary(void)
calculate_cpu_foreign_map();
+ complete(&cpu_running);
+ synchronise_count_slave(cpu);
+
/*
* irq will be enabled in ->smp_finish(), enabling it too early
* is dangerous.
Patches currently in stable-queue which might be from matija.glavinic-pecotic.ext(a)nokia.com are
queue-4.4/mips-fix-race-on-setting-and-getting-cpu_online_mask.patch
queue-4.4/mips-smp-fix-deadlock-online-race.patch