Skip to content

Commit

Permalink
media: m88ds3103: don't call a non-initalized function
Browse files Browse the repository at this point in the history
If m88d3103 chip ID is not recognized, the device is not initialized.

However, it returns from probe without any error, causing this OOPS:

[    7.689289] Unable to handle kernel NULL pointer dereference at virtual address 00000000
[    7.689297] pgd = 7b0bd7a7
[    7.689302] [00000000] *pgd=00000000
[    7.689318] Internal error: Oops: 80000005 [#1] SMP ARM
[    7.689322] Modules linked in: dvb_usb_dvbsky(+) m88ds3103 dvb_usb_v2 dvb_core videobuf2_vmalloc videobuf2_memops videobuf2_core crc32_arm_ce videodev media
[    7.689358] CPU: 3 PID: 197 Comm: systemd-udevd Not tainted 4.15.0-mcc+ #23
[    7.689361] Hardware name: BCM2835
[    7.689367] PC is at 0x0
[    7.689382] LR is at m88ds3103_attach+0x194/0x1d0 [m88ds3103]
[    7.689386] pc : [<00000000>]    lr : [<bf0ae1ec>]    psr: 60000013
[    7.689391] sp : ed8e5c20  ip : ed8c1e00  fp : ed8945c0
[    7.689395] r10: ed894000  r9 : ed894378  r8 : eda736c0
[    7.689400] r7 : ed894070  r6 : ed8e5c44  r5 : bf0bb040  r4 : eda77600
[    7.689405] r3 : 00000000  r2 : 00000000  r1 : 00000000  r0 : eda77600
[    7.689412] Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
[    7.689417] Control: 10c5383d  Table: 2d8e806a  DAC: 00000051
[    7.689423] Process systemd-udevd (pid: 197, stack limit = 0xe9dbfb63)
[    7.689428] Stack: (0xed8e5c20 to 0xed8e6000)
[    7.689439] 5c20: ed853a80 eda73640 ed894000 ed8942c0 ed853a80 bf0b9e98 ed894070 bf0b9f10
[    7.689449] 5c40: 00000000 00000000 bf08c17c c08dfc50 00000000 00000000 00000000 00000000
[    7.689459] 5c60: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[    7.689468] 5c80: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[    7.689479] 5ca0: 00000000 00000000 ed8945c0 ed8942c0 ed894000 ed894830 bf0b9e98 00000000
[    7.689490] 5cc0: ed894378 bf0a3cb4 bf0bc3b0 0000533b ed920540 00000000 00000034 bf0a6434
[    7.689500] 5ce0: ee952070 ed826600 bf0a7038 bf0a2dd8 00000001 bf0a6768 bf0a2f90 ed8943c0
[    7.689511] 5d00: 00000000 c08eca68 ed826620 ed826620 00000000 ee952070 bf0bc034 ee952000
[    7.689521] 5d20: ed826600 bf0bb080 ffffffed c0aa9e9c c0aa9dac ed826620 c16edf6c c168c2c8
[    7.689531] 5d40: c16edf70 00000000 bf0bc034 0000000d 00000000 c08e268c bf0bb080 ed826600
[    7.689541] 5d60: bf0bc034 ed826654 ed826620 bf0bc034 c164c8bc 00000000 00000001 00000000
[    7.689553] 5d80: 00000028 c08e2948 00000000 bf0bc034 c08e2848 c08e0778 ee9f0a58 ed88bab4
[    7.689563] 5da0: bf0bc034 ed90ba80 c168c1f0 c08e1934 bf0bb3bc c17045ac bf0bc034 c164c8bc
[    7.689574] 5dc0: bf0bc034 bf0bb3bc ed91f564 c08e34ec bf0bc000 c164c8bc bf0bc034 c0aa8dc4
[    7.689584] 5de0: ffffe000 00000000 bf0bf000 ed91f600 ed91f564 c03021e4 00000001 00000000
[    7.689595] 5e00: c166e040 8040003f ed853a80 bf0bc448 00000000 c1678174 ed853a80 f0f22000
[    7.689605] 5e20: f0f21fff 8040003f 014000c0 ed91e700 ed91e700 c16d8e68 00000001 ed91e6c0
[    7.689615] 5e40: bf0bc400 00000001 bf0bc400 ed91f564 00000001 00000000 00000028 c03c9a24
[    7.689625] 5e60: 00000001 c03c8c94 ed8e5f50 ed8e5f50 00000001 bf0bc400 ed91f540 c03c8cb0
[    7.689637] 5e80: bf0bc40c 00007fff bf0bc400 c03c60b0 00000000 bf0bc448 00000028 c0e09684
[    7.689647] 5ea0: 00000002 bf0bc530 c1234bf8 bf0bc5dc bf0bc514 c10ebbe8 ffffe000 bf000000
[    7.689657] 5ec0: 00011538 00000000 ed8e5f48 00000000 00000000 00000000 00000000 00000000
[    7.689666] 5ee0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
[    7.689676] 5f00: 00000000 00000000 7fffffff 00000000 00000013 b6e55a18 0000017b c0309104
[    7.689686] 5f20: ed8e4000 00000000 00510af0 c03c9430 7fffffff 00000000 00000003 00000000
[    7.689697] 5f40: 00000000 f0f0f000 00011538 00000000 f0f107b0 f0f0f000 00011538 f0f1fdb8
[    7.689707] 5f60: f0f1fbe8 f0f1b974 00004000 000041e0 bf0bc3d0 00000001 00000000 000024c4
[    7.689717] 5f80: 0000002d 0000002e 00000019 00000000 00000010 00000000 16894000 00000000
[    7.689727] 5fa0: 00000000 c0308f20 16894000 00000000 00000013 b6e55a18 00000000 b6e5652c
[    7.689737] 5fc0: 16894000 00000000 00000000 0000017b 00020000 00508110 00000000 00510af0
[    7.689748] 5fe0: bef68948 bef68938 b6e4d3d0 b6d32590 60000010 00000013 00000000 00000000
[    7.689790] [<bf0ae1ec>] (m88ds3103_attach [m88ds3103]) from [<bf0b9f10>] (dvbsky_s960c_attach+0x78/0x280 [dvb_usb_dvbsky])
[    7.689821] [<bf0b9f10>] (dvbsky_s960c_attach [dvb_usb_dvbsky]) from [<bf0a3cb4>] (dvb_usbv2_probe+0xa3c/0x1024 [dvb_usb_v2])
[    7.689849] [<bf0a3cb4>] (dvb_usbv2_probe [dvb_usb_v2]) from [<c0aa9e9c>] (usb_probe_interface+0xf0/0x2a8)
[    7.689869] [<c0aa9e9c>] (usb_probe_interface) from [<c08e268c>] (driver_probe_device+0x2f8/0x4b4)
[    7.689881] [<c08e268c>] (driver_probe_device) from [<c08e2948>] (__driver_attach+0x100/0x11c)
[    7.689895] [<c08e2948>] (__driver_attach) from [<c08e0778>] (bus_for_each_dev+0x4c/0x9c)
[    7.689909] [<c08e0778>] (bus_for_each_dev) from [<c08e1934>] (bus_add_driver+0x1c0/0x264)
[    7.689919] [<c08e1934>] (bus_add_driver) from [<c08e34ec>] (driver_register+0x78/0xf4)
[    7.689931] [<c08e34ec>] (driver_register) from [<c0aa8dc4>] (usb_register_driver+0x70/0x134)
[    7.689946] [<c0aa8dc4>] (usb_register_driver) from [<c03021e4>] (do_one_initcall+0x44/0x168)
[    7.689963] [<c03021e4>] (do_one_initcall) from [<c03c9a24>] (do_init_module+0x64/0x1f4)
[    7.689979] [<c03c9a24>] (do_init_module) from [<c03c8cb0>] (load_module+0x20a0/0x25c8)
[    7.689993] [<c03c8cb0>] (load_module) from [<c03c9430>] (SyS_finit_module+0xb4/0xec)
[    7.690007] [<c03c9430>] (SyS_finit_module) from [<c0308f20>] (ret_fast_syscall+0x0/0x54)
[    7.690018] Code: bad PC value

This may happen on normal circumstances, if, for some reason, the demod
hangs and start returning an invalid chip ID:

[   10.394395] m88ds3103 3-0068: Unknown device. Chip_id=00

So, change the logic to cause probe to fail with -ENODEV, preventing
the OOPS.

Detected while testing DVB MMAP patches on Raspberry Pi 3 with
DVBSky S960CI.

Cc: stable@vger.kernel.org
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
  • Loading branch information
mchehab committed Feb 23, 2018
1 parent 0066c76 commit b9c97c6
Showing 1 changed file with 5 additions and 2 deletions.
7 changes: 5 additions & 2 deletions drivers/media/dvb-frontends/m88ds3103.c
Original file line number Diff line number Diff line change
Expand Up @@ -1262,11 +1262,12 @@ static int m88ds3103_select(struct i2c_mux_core *muxc, u32 chan)
* New users must use I2C client binding directly!
*/
struct dvb_frontend *m88ds3103_attach(const struct m88ds3103_config *cfg,
struct i2c_adapter *i2c, struct i2c_adapter **tuner_i2c_adapter)
struct i2c_adapter *i2c,
struct i2c_adapter **tuner_i2c_adapter)
{
struct i2c_client *client;
struct i2c_board_info board_info;
struct m88ds3103_platform_data pdata;
struct m88ds3103_platform_data pdata = {};

pdata.clk = cfg->clock;
pdata.i2c_wr_max = cfg->i2c_wr_max;
Expand Down Expand Up @@ -1409,6 +1410,8 @@ static int m88ds3103_probe(struct i2c_client *client,
case M88DS3103_CHIP_ID:
break;
default:
ret = -ENODEV;
dev_err(&client->dev, "Unknown device. Chip_id=%02x\n", dev->chip_id);
goto err_kfree;
}

Expand Down

0 comments on commit b9c97c6

Please sign in to comment.