[PATCH RESEND] mfd: mc13xxx: Fix null pointer dereference in mc13xxx_common_init

Alexander Shiyan
2013-11-30T04:55:52Z

If this driver being loaded from devicetree, the pdata is NULL.
This cause kernel Oops when "fsl,mc13xxx-uses-codec" and/or
"fsl,mc13xxx-uses-touch" properties is specified.

mc13xxx spi0.0: mc13783: rev: 3.3, fin: 0, fab: 0, icid: 2/0
Unable to handle kernel NULL pointer dereference at virtual address 00000018
pgd = c0004000
[00000018] *pgd=00000000
Internal error: Oops: 5 [#1] PREEMPT ARM
CPU: 0 PID: 1 Comm: swapper Not tainted 3.12.0-next-20131105-00004-g201dd34-dirty #5
task: c7833bc0 ti: c7834000 task.ti: c7834000
PC is at mc13xxx_common_init+0x1fc/0x280
LR is at mfd_add_device+0x2a8/0x308
pc : [<c024875c>] lr : [<c0248d74>] psr: 20000013
sp : c7835d38 ip : 00000002 fp : c786a160
r10: 00000000 r9 : c786a170 r8 : 00000000
r7 : c06eab74 r6 : 00000000 r5 : 00000000 r4 : c79ffa10
r3 : 00000008 r2 : 20000013 r1 : c05079c8 r0 : c79ffa10
Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel
Control: 0005317f Table: a0004000 DAC: 00000017
Process swapper (pid: 1, stack limit = 0xc78341c0)
Stack: (0xc7835d38 to 0xc7836000)
5d20: c0507958 c79ffa10
5d40: c791ab80 0000009b 00000000 c791ab80 c05de138 c023a998 c05a9854 c0293cf8
5d60: c0293ce0 c023a774 c023a998 00000000 c791ab80 c023a998 c79ffc00 c02393ac
5d80: c785a25c c7940e54 c791ab80 c791abb4 c791ab80 c023a4cc c791ab80 c05b2704
5da0: c791ab80 c02395e8 c791ab80 00000000 c791ab88 c0237938 00000000 c01d5ed8
5dc0: 60000013 c791ab80 c791ab80 c791ab80 00000000 c786a170 00000000 c06eaa04
5de0: c786a170 c0294d08 00000001 c79ffc00 c06eab74 c791ab80 00000000 c02953a8
5e00: c79f56a0 00000000 00000063 01312d00 00000000 c79ffc00 c79ffd78 c79ffc00
5e20: c06eaa04 00000000 c79ffd70 c0296cbc c780a840 c02978c0 00000000 c051054c
5e40: c79ffd70 c787c1f0 00000000 c0462b1c 00000000 00000002 c787c1f0 c786a170
5e60: c05b2864 c786a1a4 c05b2864 00000000 c05c5800 c0579430 00000000 c023b614
5e80: c023b5fc c786a170 c05de138 c023a774 00000000 c786a170 c05b2864 c786a1a4
5ea0: 00000000 c023a994 00000000 c05b2864 c023a908 c0239034 c7825d6c c785e610
5ec0: c05b2864 c7a0bae0 c05a9138 c02397dc c051054c c01bd2f8 c05b2864 c05b2864
5ee0: c0585094 579da752 00000000 c023ad38 00000000 00000006 c0585094 c0564a24
5f00: 0000047a 00000000 579da752 00000000 00000000 a0000053 c059b070 00000001
5f20: c06eefc9 c044c6a0 000000a7 c002cd48 c7835f5c c0036f44 c051aae4 c053d7f4
5f40: 00000006 00000006 c059b064 00000006 00000006 c0585094 c058db68 c0564480
5f60: c05850a0 c05c5800 000000a7 c0564c18 00000006 00000006 c0564480 c7833bc0
5f80: c7835f9c c0036da4 00000000 c043013c 00000000 00000000 00000000 00000000
5fa0: 00000000 c0430144 00000000 c0009490 00000000 00000000 00000000 00000000
5fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
5fe0: 00000000 00000000 00000000 00000000 00000013 00000000 df7f9b78 3b477df6
[<c024875c>] (mc13xxx_common_init+0x1fc/0x280) from [<c0293cf8>] (spi_drv_probe+0x18/0x1c)
[<c0293cf8>] (spi_drv_probe+0x18/0x1c) from [<c023a774>] (driver_probe_device+0x78/0x20c)
[<c023a774>] (driver_probe_device+0x78/0x20c) from [<c02393ac>] (bus_for_each_drv+0x48/0x90)
[<c02393ac>] (bus_for_each_drv+0x48/0x90) from [<c023a4cc>] (device_attach+0x74/0x80)
[<c023a4cc>] (device_attach+0x74/0x80) from [<c02395e8>] (bus_probe_device+0x88/0xb0)
[<c02395e8>] (bus_probe_device+0x88/0xb0) from [<c0237938>] (device_add+0x31c/0x4c4)
[<c0237938>] (device_add+0x31c/0x4c4) from [<c0294d08>] (spi_add_device+0xa4/0x118)
[<c0294d08>] (spi_add_device+0xa4/0x118) from [<c02953a8>] (spi_register_master+0x53c/0x6a0)
[<c02953a8>] (spi_register_master+0x53c/0x6a0) from [<c0296cbc>] (spi_bitbang_start+0x88/0x100)
[<c0296cbc>] (spi_bitbang_start+0x88/0x100) from [<c02978c0>] (spi_imx_probe+0x3a8/0x478)
[<c02978c0>] (spi_imx_probe+0x3a8/0x478) from [<c023b614>] (platform_drv_probe+0x18/0x48)
[<c023b614>] (platform_drv_probe+0x18/0x48) from [<c023a774>] (driver_probe_device+0x78/0x20c)
[<c023a774>] (driver_probe_device+0x78/0x20c) from [<c023a994>] (__driver_attach+0x8c/0x90)
[<c023a994>] (__driver_attach+0x8c/0x90) from [<c0239034>] (bus_for_each_dev+0x5c/0x8c)
[<c0239034>] (bus_for_each_dev+0x5c/0x8c) from [<c02397dc>] (bus_add_driver+0xd4/0x1c8)
[<c02397dc>] (bus_add_driver+0xd4/0x1c8) from [<c023ad38>] (driver_register+0x78/0xf4)
[<c023ad38>] (driver_register+0x78/0xf4) from [<c0564a24>] (do_one_initcall+0x5c/0x168)
[<c0564a24>] (do_one_initcall+0x5c/0x168) from [<c0564c18>] (kernel_init_freeable+0xe8/0x1a8)
[<c0564c18>] (kernel_init_freeable+0xe8/0x1a8) from [<c0430144>] (kernel_init+0x8/0x110)
[<c0430144>] (kernel_init+0x8/0x110) from [<c0009490>] (ret_from_fork+0x14/0x24)
Code: eaffffdb e3a03008 e1a00004 e59f107c (e5962018)
---[ end trace 71265dd116f3967e ]---
Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
---
drivers/mfd/mc13xxx-core.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/mfd/mc13xxx-core.c b/drivers/mfd/mc13xxx-core.c
index dbbf8ee..625633a 100644
--- a/drivers/mfd/mc13xxx-core.c
+++ b/drivers/mfd/mc13xxx-core.c
@@ -682,14 +682,14 @@ err_revision:
if (mc13xxx->flags & MC13XXX_USE_ADC)
mc13xxx_add_subdevice(mc13xxx, "%s-adc");

- if (mc13xxx->flags & MC13XXX_USE_CODEC)
+ if ((mc13xxx->flags & MC13XXX_USE_CODEC) && pdata)
mc13xxx_add_subdevice_pdata(mc13xxx, "%s-codec",
pdata->codec, sizeof(*pdata->codec));

if (mc13xxx->flags & MC13XXX_USE_RTC)
mc13xxx_add_subdevice(mc13xxx, "%s-rtc");

- if (mc13xxx->flags & MC13XXX_USE_TOUCHSCREEN)
+ if ((mc13xxx->flags & MC13XXX_USE_CODEC) && pdata)
mc13xxx_add_subdevice_pdata(mc13xxx, "%s-ts",
&pdata->touch, sizeof(pdata->touch));

@@ -701,6 +701,10 @@ err_revision:
mc13xxx_add_subdevice_pdata(mc13xxx, "%s-pwrbutton",
pdata->buttons, sizeof(*pdata->buttons));
} else {
+ if (mc13xxx->flags & MC13XXX_USE_CODEC)
+ mc13xxx_add_subdevice(mc13xxx, "%s-codec");
+ if (mc13xxx->flags & MC13XXX_USE_TOUCHSCREEN)
+ mc13xxx_add_subdevice(mc13xxx, "%s-ts");
mc13xxx_add_subdevice(mc13xxx, "%s-regulator");
mc13xxx_add_subdevice(mc13xxx, "%s-led");
mc13xxx_add_subdevice(mc13xxx, "%s-pwrbutton");
--
1.8.3.2