[PATCH AUTOSEL 4.9 1/8] arm64: fix oops in concurrently setting insn_emulation sysctls

[PATCH AUTOSEL 4.9 1/8] arm64: fix oops in concurrently setting insn_emulation sysctls

[Sasha Levin]

From: haibinzhang (张海斌) <haibinzhang@tencent.com>

[ Upstream commit af483947d472eccb79e42059276c4deed76f99a6 ]

emulation_proc_handler() changes table->data for proc_dointvec_minmax
and can generate the following Oops if called concurrently with itself:

 | Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010
 | Internal error: Oops: 96000006 [#1] SMP
 | Call trace:
 | update_insn_emulation_mode+0xc0/0x148
 | emulation_proc_handler+0x64/0xb8
 | proc_sys_call_handler+0x9c/0xf8
 | proc_sys_write+0x18/0x20
 | __vfs_write+0x20/0x48
 | vfs_write+0xe4/0x1d0
 | ksys_write+0x70/0xf8
 | __arm64_sys_write+0x20/0x28
 | el0_svc_common.constprop.0+0x7c/0x1c0
 | el0_svc_handler+0x2c/0xa0
 | el0_svc+0x8/0x200

To fix this issue, keep the table->data as &insn->current_mode and
use container_of() to retrieve the insn pointer. Another mutex is
used to protect against the current_mode update but not for retrieving
insn_emulation as table->data is no longer changing.

Co-developed-by: hewenliang <hewenliang4@huawei.com>
Signed-off-by: hewenliang <hewenliang4@huawei.com>
Signed-off-by: Haibin Zhang <haibinzhang@tencent.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220128090324.2727688-1-hewenliang4@huawei.com
Link: https://lore.kernel.org/r/9A004C03-250B-46C5-BF39-782D7551B00E@tencent.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/arm64/kernel/armv8_deprecated.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/arch/arm64/kernel/armv8_deprecated.c b/arch/arm64/kernel/armv8_deprecated.c
index 49989207989a..89946ed1adb9 100644
--- a/arch/arm64/kernel/armv8_deprecated.c
+++ b/arch/arm64/kernel/armv8_deprecated.c
@@ -64,6 +64,7 @@ struct insn_emulation {
 static LIST_HEAD(insn_emulation);
 static int nr_insn_emulated __initdata;
 static DEFINE_RAW_SPINLOCK(insn_emulation_lock);
+static DEFINE_MUTEX(insn_emulation_mutex);
 
 static void register_emulation_hooks(struct insn_emulation_ops *ops)
 {
@@ -209,10 +210,10 @@ static int emulation_proc_handler(struct ctl_table *table, int write,
 				  loff_t *ppos)
 {
 	int ret = 0;
-	struct insn_emulation *insn = (struct insn_emulation *) table->data;
+	struct insn_emulation *insn = container_of(table->data, struct insn_emulation, current_mode);
 	enum insn_emulation_mode prev_mode = insn->current_mode;
 
-	table->data = &insn->current_mode;
+	mutex_lock(&insn_emulation_mutex);
 	ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
 
 	if (ret || !write || prev_mode == insn->current_mode)
@@ -225,7 +226,7 @@ static int emulation_proc_handler(struct ctl_table *table, int write,
 		update_insn_emulation_mode(insn, INSN_UNDEF);
 	}
 ret:
-	table->data = insn;
+	mutex_unlock(&insn_emulation_mutex);
 	return ret;
 }
 
@@ -255,7 +256,7 @@ static void __init register_insn_emulation_sysctl(struct ctl_table *table)
 		sysctl->maxlen = sizeof(int);
 
 		sysctl->procname = insn->ops->name;
-		sysctl->data = insn;
+		sysctl->data = &insn->current_mode;
 		sysctl->extra1 = &insn->min;
 		sysctl->extra2 = &insn->max;
 		sysctl->proc_handler = emulation_proc_handler;
-- 
2.35.1

[PATCH AUTOSEL 4.9 1/8] arm64: fix oops in concurrently setting insn_emulation sysctls

[Sasha Levin]

From: haibinzhang (张海斌) <haibinzhang@tencent.com>

[ Upstream commit af483947d472eccb79e42059276c4deed76f99a6 ]

emulation_proc_handler() changes table->data for proc_dointvec_minmax
and can generate the following Oops if called concurrently with itself:

 | Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010
 | Internal error: Oops: 96000006 [#1] SMP
 | Call trace:
 | update_insn_emulation_mode+0xc0/0x148
 | emulation_proc_handler+0x64/0xb8
 | proc_sys_call_handler+0x9c/0xf8
 | proc_sys_write+0x18/0x20
 | __vfs_write+0x20/0x48
 | vfs_write+0xe4/0x1d0
 | ksys_write+0x70/0xf8
 | __arm64_sys_write+0x20/0x28
 | el0_svc_common.constprop.0+0x7c/0x1c0
 | el0_svc_handler+0x2c/0xa0
 | el0_svc+0x8/0x200

To fix this issue, keep the table->data as &insn->current_mode and
use container_of() to retrieve the insn pointer. Another mutex is
used to protect against the current_mode update but not for retrieving
insn_emulation as table->data is no longer changing.

Co-developed-by: hewenliang <hewenliang4@huawei.com>
Signed-off-by: hewenliang <hewenliang4@huawei.com>
Signed-off-by: Haibin Zhang <haibinzhang@tencent.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220128090324.2727688-1-hewenliang4@huawei.com
Link: https://lore.kernel.org/r/9A004C03-250B-46C5-BF39-782D7551B00E@tencent.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/arm64/kernel/armv8_deprecated.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/arch/arm64/kernel/armv8_deprecated.c b/arch/arm64/kernel/armv8_deprecated.c
index 49989207989a..89946ed1adb9 100644
--- a/arch/arm64/kernel/armv8_deprecated.c
+++ b/arch/arm64/kernel/armv8_deprecated.c
@@ -64,6 +64,7 @@ struct insn_emulation {
 static LIST_HEAD(insn_emulation);
 static int nr_insn_emulated __initdata;
 static DEFINE_RAW_SPINLOCK(insn_emulation_lock);
+static DEFINE_MUTEX(insn_emulation_mutex);
 
 static void register_emulation_hooks(struct insn_emulation_ops *ops)
 {
@@ -209,10 +210,10 @@ static int emulation_proc_handler(struct ctl_table *table, int write,
 				  loff_t *ppos)
 {
 	int ret = 0;
-	struct insn_emulation *insn = (struct insn_emulation *) table->data;
+	struct insn_emulation *insn = container_of(table->data, struct insn_emulation, current_mode);
 	enum insn_emulation_mode prev_mode = insn->current_mode;
 
-	table->data = &insn->current_mode;
+	mutex_lock(&insn_emulation_mutex);
 	ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
 
 	if (ret || !write || prev_mode == insn->current_mode)
@@ -225,7 +226,7 @@ static int emulation_proc_handler(struct ctl_table *table, int write,
 		update_insn_emulation_mode(insn, INSN_UNDEF);
 	}
 ret:
-	table->data = insn;
+	mutex_unlock(&insn_emulation_mutex);
 	return ret;
 }
 
@@ -255,7 +256,7 @@ static void __init register_insn_emulation_sysctl(struct ctl_table *table)
 		sysctl->maxlen = sizeof(int);
 
 		sysctl->procname = insn->ops->name;
-		sysctl->data = insn;
+		sysctl->data = &insn->current_mode;
 		sysctl->extra1 = &insn->min;
 		sysctl->extra2 = &insn->max;
 		sysctl->proc_handler = emulation_proc_handler;
-- 
2.35.1


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[PATCH AUTOSEL 4.9 2/8] ext2: Add more validity checks for inode counts

[Sasha Levin]

From: Jan Kara <jack@suse.cz>

[ Upstream commit fa78f336937240d1bc598db817d638086060e7e9 ]

Add checks verifying number of inodes stored in the superblock matches
the number computed from number of inodes per group. Also verify we have
at least one block worth of inodes per group. This prevents crashes on
corrupted filesystems.

Reported-by: syzbot+d273f7d7f58afd93be48@syzkaller.appspotmail.com
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/ext2/super.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/fs/ext2/super.c b/fs/ext2/super.c
index 5ca1f73958b0..7cc83403ebe7 100644
--- a/fs/ext2/super.c
+++ b/fs/ext2/super.c
@@ -1042,9 +1042,10 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent)
 			sbi->s_frags_per_group);
 		goto failed_mount;
 	}
-	if (sbi->s_inodes_per_group > sb->s_blocksize * 8) {
+	if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
+	    sbi->s_inodes_per_group > sb->s_blocksize * 8) {
 		ext2_msg(sb, KERN_ERR,
-			"error: #inodes per group too big: %lu",
+			"error: invalid #inodes per group: %lu",
 			sbi->s_inodes_per_group);
 		goto failed_mount;
 	}
@@ -1054,6 +1055,13 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent)
 	sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
 				le32_to_cpu(es->s_first_data_block) - 1)
 					/ EXT2_BLOCKS_PER_GROUP(sb)) + 1;
+	if ((u64)sbi->s_groups_count * sbi->s_inodes_per_group !=
+	    le32_to_cpu(es->s_inodes_count)) {
+		ext2_msg(sb, KERN_ERR, "error: invalid #inodes: %u vs computed %llu",
+			 le32_to_cpu(es->s_inodes_count),
+			 (u64)sbi->s_groups_count * sbi->s_inodes_per_group);
+		goto failed_mount;
+	}
 	db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
 		   EXT2_DESC_PER_BLOCK(sb);
 	sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);
-- 
2.35.1

[PATCH AUTOSEL 4.9 3/8] ARM: dts: imx6ul: add missing properties for sram

[Sasha Levin]

From: Alexander Stein <alexander.stein@ew.tq-group.com>

[ Upstream commit 5655699cf5cff9f4c4ee703792156bdd05d1addf ]

All 3 properties are required by sram.yaml. Fixes the dtbs_check
warning:
sram@900000: '#address-cells' is a required property
sram@900000: '#size-cells' is a required property
sram@900000: 'ranges' is a required property

Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/arm/boot/dts/imx6ul.dtsi | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/arm/boot/dts/imx6ul.dtsi b/arch/arm/boot/dts/imx6ul.dtsi
index 200d9082caa4..41ae79dc4c21 100644
--- a/arch/arm/boot/dts/imx6ul.dtsi
+++ b/arch/arm/boot/dts/imx6ul.dtsi
@@ -142,6 +142,9 @@ pmu {
 		ocram: sram@00900000 {
 			compatible = "mmio-sram";
 			reg = <0x00900000 0x20000>;
+			ranges = <0 0x00900000 0x20000>;
+			#address-cells = <1>;
+			#size-cells = <1>;
 		};
 
 		dma_apbh: dma-apbh@01804000 {
-- 
2.35.1

[PATCH AUTOSEL 4.9 3/8] ARM: dts: imx6ul: add missing properties for sram

[Sasha Levin]

From: Alexander Stein <alexander.stein@ew.tq-group.com>

[ Upstream commit 5655699cf5cff9f4c4ee703792156bdd05d1addf ]

All 3 properties are required by sram.yaml. Fixes the dtbs_check
warning:
sram@900000: '#address-cells' is a required property
sram@900000: '#size-cells' is a required property
sram@900000: 'ranges' is a required property

Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/arm/boot/dts/imx6ul.dtsi | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/arm/boot/dts/imx6ul.dtsi b/arch/arm/boot/dts/imx6ul.dtsi
index 200d9082caa4..41ae79dc4c21 100644
--- a/arch/arm/boot/dts/imx6ul.dtsi
+++ b/arch/arm/boot/dts/imx6ul.dtsi
@@ -142,6 +142,9 @@ pmu {
 		ocram: sram@00900000 {
 			compatible = "mmio-sram";
 			reg = <0x00900000 0x20000>;
+			ranges = <0 0x00900000 0x20000>;
+			#address-cells = <1>;
+			#size-cells = <1>;
 		};
 
 		dma_apbh: dma-apbh@01804000 {
-- 
2.35.1


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[PATCH AUTOSEL 4.9 4/8] ARM: dts: imx6ul: fix qspi node compatible

[Sasha Levin]

From: Alexander Stein <alexander.stein@ew.tq-group.com>

[ Upstream commit 0c6cf86e1ab433b2d421880fdd9c6e954f404948 ]

imx6ul is not compatible to imx6sx, both have different erratas.
Fixes the dt_binding_check warning:
spi@21e0000: compatible: 'oneOf' conditional failed, one must be fixed:
['fsl,imx6ul-qspi', 'fsl,imx6sx-qspi'] is too long
Additional items are not allowed ('fsl,imx6sx-qspi' was unexpected)
'fsl,imx6ul-qspi' is not one of ['fsl,ls1043a-qspi']
'fsl,imx6ul-qspi' is not one of ['fsl,imx8mq-qspi']
'fsl,ls1021a-qspi' was expected
'fsl,imx7d-qspi' was expected

Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/arm/boot/dts/imx6ul.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/imx6ul.dtsi b/arch/arm/boot/dts/imx6ul.dtsi
index 41ae79dc4c21..5ec16b26f7c7 100644
--- a/arch/arm/boot/dts/imx6ul.dtsi
+++ b/arch/arm/boot/dts/imx6ul.dtsi
@@ -866,7 +866,7 @@ lcdif: lcdif@021c8000 {
 			qspi: qspi@021e0000 {
 				#address-cells = <1>;
 				#size-cells = <0>;
-				compatible = "fsl,imx6ul-qspi", "fsl,imx6sx-qspi";
+				compatible = "fsl,imx6ul-qspi";
 				reg = <0x021e0000 0x4000>, <0x60000000 0x10000000>;
 				reg-names = "QuadSPI", "QuadSPI-memory";
 				interrupts = <GIC_SPI 107 IRQ_TYPE_LEVEL_HIGH>;
-- 
2.35.1

[PATCH AUTOSEL 4.9 4/8] ARM: dts: imx6ul: fix qspi node compatible

[Sasha Levin]

From: Alexander Stein <alexander.stein@ew.tq-group.com>

[ Upstream commit 0c6cf86e1ab433b2d421880fdd9c6e954f404948 ]

imx6ul is not compatible to imx6sx, both have different erratas.
Fixes the dt_binding_check warning:
spi@21e0000: compatible: 'oneOf' conditional failed, one must be fixed:
['fsl,imx6ul-qspi', 'fsl,imx6sx-qspi'] is too long
Additional items are not allowed ('fsl,imx6sx-qspi' was unexpected)
'fsl,imx6ul-qspi' is not one of ['fsl,ls1043a-qspi']
'fsl,imx6ul-qspi' is not one of ['fsl,imx8mq-qspi']
'fsl,ls1021a-qspi' was expected
'fsl,imx7d-qspi' was expected

Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/arm/boot/dts/imx6ul.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/boot/dts/imx6ul.dtsi b/arch/arm/boot/dts/imx6ul.dtsi
index 41ae79dc4c21..5ec16b26f7c7 100644
--- a/arch/arm/boot/dts/imx6ul.dtsi
+++ b/arch/arm/boot/dts/imx6ul.dtsi
@@ -866,7 +866,7 @@ lcdif: lcdif@021c8000 {
 			qspi: qspi@021e0000 {
 				#address-cells = <1>;
 				#size-cells = <0>;
-				compatible = "fsl,imx6ul-qspi", "fsl,imx6sx-qspi";
+				compatible = "fsl,imx6ul-qspi";
 				reg = <0x021e0000 0x4000>, <0x60000000 0x10000000>;
 				reg-names = "QuadSPI", "QuadSPI-memory";
 				interrupts = <GIC_SPI 107 IRQ_TYPE_LEVEL_HIGH>;
-- 
2.35.1


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[PATCH AUTOSEL 4.9 5/8] ACPI: LPSS: Fix missing check in register_device_clock()

[Sasha Levin]

From: huhai <huhai@kylinos.cn>

[ Upstream commit b4f1f61ed5928b1128e60e38d0dffa16966f06dc ]

register_device_clock() misses a check for platform_device_register_simple().
Add a check to fix it.

Signed-off-by: huhai <huhai@kylinos.cn>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/acpi/acpi_lpss.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c
index a9158858f54c..6ca4b3dc11ca 100644
--- a/drivers/acpi/acpi_lpss.c
+++ b/drivers/acpi/acpi_lpss.c
@@ -330,6 +330,9 @@ static int register_device_clock(struct acpi_device *adev,
 	if (!lpss_clk_dev)
 		lpt_register_clock_device();
 
+	if (IS_ERR(lpss_clk_dev))
+		return PTR_ERR(lpss_clk_dev);
+
 	clk_data = platform_get_drvdata(lpss_clk_dev);
 	if (!clk_data)
 		return -ENODEV;
-- 
2.35.1

[PATCH AUTOSEL 4.9 6/8] hwmon: (sht15) Fix wrong assumptions in device remove callback

[Sasha Levin]

From: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

[ Upstream commit 7d4edccc9bbfe1dcdff641343f7b0c6763fbe774 ]

Taking a lock at the beginning of .remove() doesn't prevent new readers.
With the existing approach it can happen, that a read occurs just when
the lock was taken blocking the reader until the lock is released at the
end of the remove callback which then accessed *data that is already
freed then.

To actually fix this problem the hwmon core needs some adaption. Until
this is implemented take the optimistic approach of assuming that all
readers are gone after hwmon_device_unregister() and
sysfs_remove_group() as most other drivers do. (And once the core
implements that, taking the lock would deadlock.)

So drop the lock, move the reset to after device unregistration to keep
the device in a workable state until it's deregistered. Also add a error
message in case the reset fails and return 0 anyhow. (Returning an error
code, doesn't stop the platform device unregistration and only results
in a little helpful error message before the devm cleanup handlers are
called.)

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20220725194344.150098-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/hwmon/sht15.c | 17 ++++++-----------
 1 file changed, 6 insertions(+), 11 deletions(-)

diff --git a/drivers/hwmon/sht15.c b/drivers/hwmon/sht15.c
index a2fdbb7d20ed..3bff2dce3123 100644
--- a/drivers/hwmon/sht15.c
+++ b/drivers/hwmon/sht15.c
@@ -1040,25 +1040,20 @@ static int sht15_probe(struct platform_device *pdev)
 static int sht15_remove(struct platform_device *pdev)
 {
 	struct sht15_data *data = platform_get_drvdata(pdev);
+	int ret;
 
-	/*
-	 * Make sure any reads from the device are done and
-	 * prevent new ones beginning
-	 */
-	mutex_lock(&data->read_lock);
-	if (sht15_soft_reset(data)) {
-		mutex_unlock(&data->read_lock);
-		return -EFAULT;
-	}
 	hwmon_device_unregister(data->hwmon_dev);
 	sysfs_remove_group(&pdev->dev.kobj, &sht15_attr_group);
+
+	ret = sht15_soft_reset(data);
+	if (ret)
+		dev_err(&pdev->dev, "Failed to reset device (%pe)\n", ERR_PTR(ret));
+
 	if (!IS_ERR(data->reg)) {
 		regulator_unregister_notifier(data->reg, &data->nb);
 		regulator_disable(data->reg);
 	}
 
-	mutex_unlock(&data->read_lock);
-
 	return 0;
 }
 
-- 
2.35.1

[PATCH AUTOSEL 4.9 7/8] PM: hibernate: defer device probing when resuming from hibernation

[Sasha Levin]

From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>

[ Upstream commit 8386c414e27caba8501119948e9551e52b527f59 ]

syzbot is reporting hung task at misc_open() [1], for there is a race
window of AB-BA deadlock which involves probe_count variable. Currently
wait_for_device_probe() from snapshot_open() from misc_open() can sleep
forever with misc_mtx held if probe_count cannot become 0.

When a device is probed by hub_event() work function, probe_count is
incremented before the probe function starts, and probe_count is
decremented after the probe function completed.

There are three cases that can prevent probe_count from dropping to 0.

  (a) A device being probed stopped responding (i.e. broken/malicious
      hardware).

  (b) A process emulating a USB device using /dev/raw-gadget interface
      stopped responding for some reason.

  (c) New device probe requests keeps coming in before existing device
      probe requests complete.

The phenomenon syzbot is reporting is (b). A process which is holding
system_transition_mutex and misc_mtx is waiting for probe_count to become
0 inside wait_for_device_probe(), but the probe function which is called
 from hub_event() work function is waiting for the processes which are
blocked at mutex_lock(&misc_mtx) to respond via /dev/raw-gadget interface.

This patch mitigates (b) by deferring wait_for_device_probe() from
snapshot_open() to snapshot_write() and snapshot_ioctl(). Please note that
the possibility of (b) remains as long as any thread which is emulating a
USB device via /dev/raw-gadget interface can be blocked by uninterruptible
blocking operations (e.g. mutex_lock()).

Please also note that (a) and (c) are not addressed. Regarding (c), we
should change the code to wait for only one device which contains the
image for resuming from hibernation. I don't know how to address (a), for
use of timeout for wait_for_device_probe() might result in loss of user
data in the image. Maybe we should require the userland to wait for the
image device before opening /dev/snapshot interface.

Link: https://syzkaller.appspot.com/bug?extid=358c9ab4c93da7b7238c [1]
Reported-by: syzbot <syzbot+358c9ab4c93da7b7238c@syzkaller.appspotmail.com>
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: syzbot <syzbot+358c9ab4c93da7b7238c@syzkaller.appspotmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 kernel/power/user.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/kernel/power/user.c b/kernel/power/user.c
index bc6dde1f1567..a84f9e549ad5 100644
--- a/kernel/power/user.c
+++ b/kernel/power/user.c
@@ -29,6 +29,7 @@
 
 #include "power.h"
 
+static bool need_wait;
 
 #define SNAPSHOT_MINOR	231
 
@@ -82,7 +83,7 @@ static int snapshot_open(struct inode *inode, struct file *filp)
 		 * Resuming.  We may need to wait for the image device to
 		 * appear.
 		 */
-		wait_for_device_probe();
+		need_wait = true;
 
 		data->swap = -1;
 		data->mode = O_WRONLY;
@@ -174,6 +175,11 @@ static ssize_t snapshot_write(struct file *filp, const char __user *buf,
 	ssize_t res;
 	loff_t pg_offp = *offp & ~PAGE_MASK;
 
+	if (need_wait) {
+		wait_for_device_probe();
+		need_wait = false;
+	}
+
 	lock_system_sleep();
 
 	data = filp->private_data;
@@ -209,6 +215,11 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd,
 	loff_t size;
 	sector_t offset;
 
+	if (need_wait) {
+		wait_for_device_probe();
+		need_wait = false;
+	}
+
 	if (_IOC_TYPE(cmd) != SNAPSHOT_IOC_MAGIC)
 		return -ENOTTY;
 	if (_IOC_NR(cmd) > SNAPSHOT_IOC_MAXNR)
-- 
2.35.1

[PATCH AUTOSEL 4.9 8/8] selinux: Add boundary check in put_entry()

[Sasha Levin]

From: Xiu Jianfeng <xiujianfeng@huawei.com>

[ Upstream commit 15ec76fb29be31df2bccb30fc09875274cba2776 ]

Just like next_entry(), boundary check is necessary to prevent memory
out-of-bound access.

Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 security/selinux/ss/policydb.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/security/selinux/ss/policydb.h b/security/selinux/ss/policydb.h
index 725d5945a97e..178d8804ecb1 100644
--- a/security/selinux/ss/policydb.h
+++ b/security/selinux/ss/policydb.h
@@ -349,6 +349,8 @@ static inline int put_entry(const void *buf, size_t bytes, int num, struct polic
 {
 	size_t len = bytes * num;
 
+	if (len > fp->len)
+		return -EINVAL;
 	memcpy(fp->data, buf, len);
 	fp->data += len;
 	fp->len -= len;
-- 
2.35.1