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From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	stable@vger.kernel.org, Evan Green <evgreen@chromium.org>,
	Matthias Kaehlcke <mka@chromium.org>,
	Stable@vger.kernel.org,
	Jonathan Cameron <Jonathan.Cameron@huawei.com>
Subject: [PATCH 4.20 43/65] iio: adc: qcom-spmi-adc5: Initialize prescale properly
Date: Fri, 11 Jan 2019 15:15:29 +0100	[thread overview]
Message-ID: <20190111131102.331712210@linuxfoundation.org> (raw)
In-Reply-To: <20190111131055.331350141@linuxfoundation.org>

4.20-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Evan Green <evgreen@chromium.org>

commit db23d88756abd38e0995ea8449d0025b3de4b26b upstream.

adc5_get_dt_data uses a local, prop, feeds it to adc5_get_dt_channel_data,
and then puts the result into adc->chan_props. The problem is
adc5_get_dt_channel_data may not initialize that structure fully, so a
garbage value is used for prescale if the optional "qcom,pre-scaling" is
not defined in DT. adc5_read_raw then uses this as an array index,
generating a crash that looks like this:

[    6.683186] Unable to handle kernel paging request at virtual address ffffff90e78c7964
Call trace:
qcom_vadc_scale_code_voltage_factor+0x74/0x104
qcom_vadc_scale_hw_calib_die_temp+0x20/0x60
qcom_adc5_hw_scale+0x78/0xa4
adc5_read_raw+0x3d0/0x65c
iio_channel_read+0x240/0x30c
iio_read_channel_processed+0x10c/0x150
qpnp_tm_get_temp+0xc0/0x40c
of_thermal_get_temp+0x7c/0x98
thermal_zone_get_temp+0xac/0xd8
thermal_zone_device_update+0xc0/0x38c
qpnp_tm_probe+0x624/0x81c
platform_drv_probe+0xe4/0x11c
really_probe+0x188/0x3fc
driver_probe_device+0xb8/0x188
__device_attach_driver+0x114/0x180
bus_for_each_drv+0xd8/0x118
__device_attach+0x180/0x27c
device_initial_probe+0x20/0x2c
bus_probe_device+0x78/0x124
deferred_probe_work_func+0xfc/0x138
process_one_work+0x3d8/0x8b0
process_scheduled_works+0x48/0x6c
worker_thread+0x488/0x7cc
kthread+0x24c/0x264
ret_from_fork+0x10/0x18

Unfortunately, when I went to add the initializer for this and tried to
boot it, my machine shut down immediately, complaining that it was
hotter than the sun. It appears that adc5_chans_pmic and adc5_chans_rev2
were initializing prescale_index as if it were directly a divisor,
rather than the index into adc5_prescale_ratios that it is.

Fix the uninitialized value, and change the static initialization to use
indices into adc5_prescale_ratios.

Signed-off-by: Evan Green <evgreen@chromium.org>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/iio/adc/qcom-spmi-adc5.c |   58 ++++++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 27 deletions(-)

--- a/drivers/iio/adc/qcom-spmi-adc5.c
+++ b/drivers/iio/adc/qcom-spmi-adc5.c
@@ -423,6 +423,7 @@ struct adc5_channels {
 	enum vadc_scale_fn_type scale_fn_type;
 };
 
+/* In these definitions, _pre refers to an index into adc5_prescale_ratios. */
 #define ADC5_CHAN(_dname, _type, _mask, _pre, _scale)			\
 	{								\
 		.datasheet_name = _dname,				\
@@ -443,63 +444,63 @@ struct adc5_channels {
 		  _pre, _scale)						\
 
 static const struct adc5_channels adc5_chans_pmic[ADC5_MAX_CHANNEL] = {
-	[ADC5_REF_GND]		= ADC5_CHAN_VOLT("ref_gnd", 1,
+	[ADC5_REF_GND]		= ADC5_CHAN_VOLT("ref_gnd", 0,
 					SCALE_HW_CALIB_DEFAULT)
-	[ADC5_1P25VREF]		= ADC5_CHAN_VOLT("vref_1p25", 1,
+	[ADC5_1P25VREF]		= ADC5_CHAN_VOLT("vref_1p25", 0,
 					SCALE_HW_CALIB_DEFAULT)
-	[ADC5_VPH_PWR]		= ADC5_CHAN_VOLT("vph_pwr", 3,
+	[ADC5_VPH_PWR]		= ADC5_CHAN_VOLT("vph_pwr", 1,
 					SCALE_HW_CALIB_DEFAULT)
-	[ADC5_VBAT_SNS]		= ADC5_CHAN_VOLT("vbat_sns", 3,
+	[ADC5_VBAT_SNS]		= ADC5_CHAN_VOLT("vbat_sns", 1,
 					SCALE_HW_CALIB_DEFAULT)
-	[ADC5_DIE_TEMP]		= ADC5_CHAN_TEMP("die_temp", 1,
+	[ADC5_DIE_TEMP]		= ADC5_CHAN_TEMP("die_temp", 0,
 					SCALE_HW_CALIB_PMIC_THERM)
-	[ADC5_USB_IN_I]		= ADC5_CHAN_VOLT("usb_in_i_uv", 1,
+	[ADC5_USB_IN_I]		= ADC5_CHAN_VOLT("usb_in_i_uv", 0,
 					SCALE_HW_CALIB_DEFAULT)
-	[ADC5_USB_IN_V_16]	= ADC5_CHAN_VOLT("usb_in_v_div_16", 16,
+	[ADC5_USB_IN_V_16]	= ADC5_CHAN_VOLT("usb_in_v_div_16", 8,
 					SCALE_HW_CALIB_DEFAULT)
-	[ADC5_CHG_TEMP]		= ADC5_CHAN_TEMP("chg_temp", 1,
+	[ADC5_CHG_TEMP]		= ADC5_CHAN_TEMP("chg_temp", 0,
 					SCALE_HW_CALIB_PM5_CHG_TEMP)
 	/* Charger prescales SBUx and MID_CHG to fit within 1.8V upper unit */
-	[ADC5_SBUx]		= ADC5_CHAN_VOLT("chg_sbux", 3,
+	[ADC5_SBUx]		= ADC5_CHAN_VOLT("chg_sbux", 1,
 					SCALE_HW_CALIB_DEFAULT)
-	[ADC5_MID_CHG_DIV6]	= ADC5_CHAN_VOLT("chg_mid_chg", 6,
+	[ADC5_MID_CHG_DIV6]	= ADC5_CHAN_VOLT("chg_mid_chg", 3,
 					SCALE_HW_CALIB_DEFAULT)
-	[ADC5_XO_THERM_100K_PU]	= ADC5_CHAN_TEMP("xo_therm", 1,
+	[ADC5_XO_THERM_100K_PU]	= ADC5_CHAN_TEMP("xo_therm", 0,
 					SCALE_HW_CALIB_XOTHERM)
-	[ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 1,
+	[ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 0,
 					SCALE_HW_CALIB_THERM_100K_PULLUP)
-	[ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 1,
+	[ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 0,
 					SCALE_HW_CALIB_THERM_100K_PULLUP)
-	[ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 1,
+	[ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 0,
 					SCALE_HW_CALIB_THERM_100K_PULLUP)
-	[ADC5_AMUX_THM2]	= ADC5_CHAN_TEMP("amux_thm2", 1,
+	[ADC5_AMUX_THM2]	= ADC5_CHAN_TEMP("amux_thm2", 0,
 					SCALE_HW_CALIB_PM5_SMB_TEMP)
 };
 
 static const struct adc5_channels adc5_chans_rev2[ADC5_MAX_CHANNEL] = {
-	[ADC5_REF_GND]		= ADC5_CHAN_VOLT("ref_gnd", 1,
+	[ADC5_REF_GND]		= ADC5_CHAN_VOLT("ref_gnd", 0,
 					SCALE_HW_CALIB_DEFAULT)
-	[ADC5_1P25VREF]		= ADC5_CHAN_VOLT("vref_1p25", 1,
+	[ADC5_1P25VREF]		= ADC5_CHAN_VOLT("vref_1p25", 0,
 					SCALE_HW_CALIB_DEFAULT)
-	[ADC5_VPH_PWR]		= ADC5_CHAN_VOLT("vph_pwr", 3,
+	[ADC5_VPH_PWR]		= ADC5_CHAN_VOLT("vph_pwr", 1,
 					SCALE_HW_CALIB_DEFAULT)
-	[ADC5_VBAT_SNS]		= ADC5_CHAN_VOLT("vbat_sns", 3,
+	[ADC5_VBAT_SNS]		= ADC5_CHAN_VOLT("vbat_sns", 1,
 					SCALE_HW_CALIB_DEFAULT)
-	[ADC5_VCOIN]		= ADC5_CHAN_VOLT("vcoin", 3,
+	[ADC5_VCOIN]		= ADC5_CHAN_VOLT("vcoin", 1,
 					SCALE_HW_CALIB_DEFAULT)
-	[ADC5_DIE_TEMP]		= ADC5_CHAN_TEMP("die_temp", 1,
+	[ADC5_DIE_TEMP]		= ADC5_CHAN_TEMP("die_temp", 0,
 					SCALE_HW_CALIB_PMIC_THERM)
-	[ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 1,
+	[ADC5_AMUX_THM1_100K_PU] = ADC5_CHAN_TEMP("amux_thm1_100k_pu", 0,
 					SCALE_HW_CALIB_THERM_100K_PULLUP)
-	[ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 1,
+	[ADC5_AMUX_THM2_100K_PU] = ADC5_CHAN_TEMP("amux_thm2_100k_pu", 0,
 					SCALE_HW_CALIB_THERM_100K_PULLUP)
-	[ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 1,
+	[ADC5_AMUX_THM3_100K_PU] = ADC5_CHAN_TEMP("amux_thm3_100k_pu", 0,
 					SCALE_HW_CALIB_THERM_100K_PULLUP)
-	[ADC5_AMUX_THM4_100K_PU] = ADC5_CHAN_TEMP("amux_thm4_100k_pu", 1,
+	[ADC5_AMUX_THM4_100K_PU] = ADC5_CHAN_TEMP("amux_thm4_100k_pu", 0,
 					SCALE_HW_CALIB_THERM_100K_PULLUP)
-	[ADC5_AMUX_THM5_100K_PU] = ADC5_CHAN_TEMP("amux_thm5_100k_pu", 1,
+	[ADC5_AMUX_THM5_100K_PU] = ADC5_CHAN_TEMP("amux_thm5_100k_pu", 0,
 					SCALE_HW_CALIB_THERM_100K_PULLUP)
-	[ADC5_XO_THERM_100K_PU]	= ADC5_CHAN_TEMP("xo_therm_100k_pu", 1,
+	[ADC5_XO_THERM_100K_PU]	= ADC5_CHAN_TEMP("xo_therm_100k_pu", 0,
 					SCALE_HW_CALIB_THERM_100K_PULLUP)
 };
 
@@ -558,6 +559,9 @@ static int adc5_get_dt_channel_data(stru
 			return ret;
 		}
 		prop->prescale = ret;
+	} else {
+		prop->prescale =
+			adc->data->adc_chans[prop->channel].prescale_index;
 	}
 
 	ret = of_property_read_u32(node, "qcom,hw-settle-time", &value);



  parent reply	other threads:[~2019-01-11 14:46 UTC|newest]

Thread overview: 75+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-01-11 14:14 [PATCH 4.20 00/65] 4.20.2-stable review Greg Kroah-Hartman
2019-01-11 14:14 ` [PATCH 4.20 01/65] scsi: zfcp: fix posting too many status read buffers leading to adapter shutdown Greg Kroah-Hartman
2019-01-11 14:14 ` [PATCH 4.20 02/65] scsi: lpfc: do not set queue->page_count to 0 if pc_sli4_params.wqpcnt is invalid Greg Kroah-Hartman
2019-01-11 14:14 ` [PATCH 4.20 03/65] fork: record start_time late Greg Kroah-Hartman
2019-01-11 14:14 ` [PATCH 4.20 04/65] zram: fix double free backing device Greg Kroah-Hartman
2019-01-11 14:14 ` [PATCH 4.20 05/65] hwpoison, memory_hotplug: allow hwpoisoned pages to be offlined Greg Kroah-Hartman
2019-01-11 14:14 ` [PATCH 4.20 06/65] mm, devm_memremap_pages: mark devm_memremap_pages() EXPORT_SYMBOL_GPL Greg Kroah-Hartman
2019-01-11 14:14 ` [PATCH 4.20 07/65] mm, devm_memremap_pages: kill mapping "System RAM" support Greg Kroah-Hartman
2019-01-11 14:14 ` [PATCH 4.20 08/65] mm, devm_memremap_pages: fix shutdown handling Greg Kroah-Hartman
2019-01-11 14:14 ` [PATCH 4.20 09/65] memcg, oom: notify on oom killer invocation from the charge path Greg Kroah-Hartman
2019-01-11 14:14 ` [PATCH 4.20 10/65] sunrpc: fix cache_head leak due to queued request Greg Kroah-Hartman
2019-01-11 14:14 ` [PATCH 4.20 11/65] sunrpc: use SVC_NET() in svcauth_gss_* functions Greg Kroah-Hartman
2019-01-11 14:14 ` [PATCH 4.20 12/65] mm, devm_memremap_pages: add MEMORY_DEVICE_PRIVATE support Greg Kroah-Hartman
2019-01-11 14:14 ` [PATCH 4.20 13/65] mm, hmm: use devm semantics for hmm_devmem_{add, remove} Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 14/65] mm, hmm: replace hmm_devmem_pages_create() with devm_memremap_pages() Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 15/65] mm, hmm: mark hmm_devmem_{add, add_resource} EXPORT_SYMBOL_GPL Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 16/65] mm, swap: fix swapoff with KSM pages Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 17/65] media: cx23885: only reset DMA on problematic CPUs Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 18/65] ALSA: cs46xx: Potential NULL dereference in probe Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 19/65] ALSA: usb-audio: Avoid access before bLength check in build_audio_procunit() Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 20/65] ALSA: usb-audio: Check mixer unit descriptors more strictly Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 21/65] ALSA: usb-audio: Fix an out-of-bound read in create_composite_quirks Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 22/65] ALSA: usb-audio: Always check descriptor sizes in parser code Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 23/65] srcu: Lock srcu_data structure in srcu_gp_start() Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 24/65] driver core: Add missing dev->bus->need_parent_lock checks Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 25/65] Fix failure path in alloc_pid() Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 26/65] block: deactivate blk_stat timer in wbt_disable_default() Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 27/65] block: mq-deadline: Fix write completion handling Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 28/65] dm: do not allow readahead to limit IO size Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 29/65] dlm: fixed memory leaks after failed ls_remove_names allocation Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 30/65] dlm: possible memory leak on error path in create_lkb() Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 31/65] dlm: lost put_lkb on error path in receive_convert() and receive_unlock() Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 32/65] dlm: memory leaks on error path in dlm_user_request() Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 33/65] gfs2: Get rid of potential double-freeing in gfs2_create_inode Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 34/65] gfs2: Fix loop in gfs2_rbm_find Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 35/65] b43: Fix error in cordic routine Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 36/65] selinux: policydb - fix byte order and alignment issues Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 37/65] PCI / PM: Allow runtime PM without callback functions Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 38/65] lockd: Show pid of lockd for remote locks Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 39/65] xprtrdma: Yet another double DMA-unmap Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 40/65] nfsd4: zero-length WRITE should succeed Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 41/65] Revert "powerpc/tm: Unset MSR[TS] if not recheckpointing" Greg Kroah-Hartman
2019-01-12 21:35   ` Christoph Biedl
2019-01-13  7:11     ` Greg Kroah-Hartman
2019-01-14  0:00       ` Michael Ellerman
2019-01-14  8:10         ` Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 42/65] powerpc/tm: Set MSR[TS] just prior to recheckpoint Greg Kroah-Hartman
2019-01-11 14:15 ` Greg Kroah-Hartman [this message]
2019-01-11 14:15 ` [PATCH 4.20 44/65] iio: dac: ad5686: fix bit shift read register Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 45/65] 9p/net: put a lower bound on msize Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 46/65] rxe: fix error completion wr_id and qp_num Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 47/65] stm class: Fix a module refcount leak in policy creation error path Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 48/65] RDMA/srpt: Fix a use-after-free in the channel release code Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 49/65] RDMA/iwcm: Dont copy past the end of dev_name() string Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 50/65] iommu/vt-d: Handle domain agaw being less than iommu agaw Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 51/65] sched/fair: Fix infinite loop in update_blocked_averages() by reverting a9e7f6544b9c Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 52/65] ceph: dont update importing caps mseq when handing cap export Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 53/65] video: fbdev: pxafb: Fix "WARNING: invalid free of devm_ allocated data" Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 54/65] drivers/perf: hisi: Fixup one DDRC PMU register offset Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 55/65] powerpc/4xx/ocm: Fix compilation error due to PAGE_KERNEL usage Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 56/65] selftests: Fix test errors related to lib.mk khdr target Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 57/65] genwqe: Fix size check Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 58/65] intel_th: msu: Fix an off-by-one in attribute store Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 59/65] power: supply: olpc_battery: correct the temperature units Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 60/65] of: of_node_get()/of_node_put() nodes held in phandle cache Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 61/65] of: __of_detach_node() - remove node from " Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 62/65] lib: fix build failure in CONFIG_DEBUG_VIRTUAL test Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 63/65] drm/nouveau/drm/nouveau: Check rc from drm_dp_mst_topology_mgr_resume() Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 64/65] drm/vc4: Set ->is_yuv to false when num_planes == 1 Greg Kroah-Hartman
2019-01-11 14:15 ` [PATCH 4.20 65/65] drm/rockchip: psr: do not dereference encoder before it is null checked Greg Kroah-Hartman
2019-01-11 21:35 ` [PATCH 4.20 00/65] 4.20.2-stable review shuah
2019-01-12  8:03   ` Greg Kroah-Hartman
2019-01-12  8:28 ` Naresh Kamboju
2019-01-12 17:35   ` Greg Kroah-Hartman
2019-01-12 17:45 ` Guenter Roeck

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