From: Guenter Roeck linux@roeck-us.net
[ Upstream commit 79da533d3cc717ccc05ddbd3190da8a72bc2408b ]
Paweł Marciniak reports the following crash, observed when clearing the chassis intrusion alarm.
BUG: kernel NULL pointer dereference, address: 0000000000000028 PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 3 PID: 4815 Comm: bash Tainted: G S 5.16.2-200.fc35.x86_64 #1 Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./Z97 Extreme4, BIOS P2.60A 05/03/2018 RIP: 0010:clear_caseopen+0x5a/0x120 [nct6775] Code: 68 70 e8 e9 32 b1 e3 85 c0 0f 85 d2 00 00 00 48 83 7c 24 ... RSP: 0018:ffffabcb02803dd8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000002 RCX: 0000000000000000 RDX: ffff8e8808192880 RSI: 0000000000000000 RDI: ffff8e87c7509a68 RBP: 0000000000000000 R08: 0000000000000001 R09: 000000000000000a R10: 000000000000000a R11: f000000000000000 R12: 000000000000001f R13: ffff8e87c7509828 R14: ffff8e87c7509a68 R15: ffff8e88494527a0 FS: 00007f4db9151740(0000) GS:ffff8e8ebfec0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000028 CR3: 0000000166b66001 CR4: 00000000001706e0 Call Trace: <TASK> kernfs_fop_write_iter+0x11c/0x1b0 new_sync_write+0x10b/0x180 vfs_write+0x209/0x2a0 ksys_write+0x4f/0xc0 do_syscall_64+0x3b/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae
The problem is that the device passed to clear_caseopen() is the hwmon device, not the platform device, and the platform data is not set in the hwmon device. Store the pointer to sio_data in struct nct6775_data and get if from there if needed.
Fixes: 2e7b9886968b ("hwmon: (nct6775) Use superio_*() function pointers in sio_data.") Cc: Denis Pauk pauk.denis@gmail.com Cc: Bernhard Seibold mail@bernhard-seibold.de Reported-by: Paweł Marciniak pmarciniak@lodz.home.pl Tested-by: Denis Pauk pauk.denis@gmail.com Signed-off-by: Guenter Roeck linux@roeck-us.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/hwmon/nct6775.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/hwmon/nct6775.c b/drivers/hwmon/nct6775.c index 57ce8633a7256..3496a823e4d4f 100644 --- a/drivers/hwmon/nct6775.c +++ b/drivers/hwmon/nct6775.c @@ -1175,7 +1175,7 @@ static inline u8 in_to_reg(u32 val, u8 nr)
struct nct6775_data { int addr; /* IO base of hw monitor block */ - int sioreg; /* SIO register address */ + struct nct6775_sio_data *sio_data; enum kinds kind; const char *name;
@@ -3561,7 +3561,7 @@ clear_caseopen(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct nct6775_data *data = dev_get_drvdata(dev); - struct nct6775_sio_data *sio_data = dev_get_platdata(dev); + struct nct6775_sio_data *sio_data = data->sio_data; int nr = to_sensor_dev_attr(attr)->index - INTRUSION_ALARM_BASE; unsigned long val; u8 reg; @@ -3969,7 +3969,7 @@ static int nct6775_probe(struct platform_device *pdev) return -ENOMEM;
data->kind = sio_data->kind; - data->sioreg = sio_data->sioreg; + data->sio_data = sio_data;
if (sio_data->access == access_direct) { data->addr = res->start;