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staging/rdma/hfi1: Guard i2c access against cp

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An attempt to cp or cat /sys/kernel/debug/hfi1/hfi1_0/i2c1
produces this message:

hfi1 0000:81:00.0: hfi1_0: IB0:1 I2C failed even retrying

Fix the issue by explicitly rejecting a simple cat/cp with an
-EINVAL error return.

Reviewed-by: Easwar Hariharan <easwar.hariharan@intel.com>
Signed-off-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
This commit is contained in:
Dean Luick 2016-02-18 11:12:51 -08:00 committed by Doug Ledford
parent 9debaaecb9
commit 7b47622d78
1 changed files with 20 additions and 8 deletions
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28
drivers/staging/rdma/hfi1/debugfs.c
View file

@ -446,6 +446,16 @@ static ssize_t __i2c_debugfs_write(struct file *file, const char __user *buf,
rcu_read_lock();
ppd = private2ppd(file);
/* byte offset format: [offsetSize][i2cAddr][offsetHigh][offsetLow] */
i2c_addr = (*ppos >> 16) & 0xffff;
offset = *ppos & 0xffff;
/* explicitly reject invalid address 0 to catch cp and cat */
if (i2c_addr == 0) {
ret = -EINVAL;
goto _return;
}
buff = kmalloc(count, GFP_KERNEL);
if (!buff) {
ret = -ENOMEM;
@ -458,10 +468,6 @@ static ssize_t __i2c_debugfs_write(struct file *file, const char __user *buf,
goto _free;
}
/* byte offset format: [offsetSize][i2cAddr][offsetHigh][offsetLow] */
i2c_addr = (*ppos >> 16) & 0xffff;
offset = *ppos & 0xffff;
total_written = i2c_write(ppd, target, i2c_addr, offset, buff, count);
if (total_written < 0) {
ret = total_written;
@ -507,16 +513,22 @@ static ssize_t __i2c_debugfs_read(struct file *file, char __user *buf,
rcu_read_lock();
ppd = private2ppd(file);
/* byte offset format: [offsetSize][i2cAddr][offsetHigh][offsetLow] */
i2c_addr = (*ppos >> 16) & 0xffff;
offset = *ppos & 0xffff;
/* explicitly reject invalid address 0 to catch cp and cat */
if (i2c_addr == 0) {
ret = -EINVAL;
goto _return;
}
buff = kmalloc(count, GFP_KERNEL);
if (!buff) {
ret = -ENOMEM;
goto _return;
}
/* byte offset format: [offsetSize][i2cAddr][offsetHigh][offsetLow] */
i2c_addr = (*ppos >> 16) & 0xffff;
offset = *ppos & 0xffff;
total_read = i2c_read(ppd, target, i2c_addr, offset, buff, count);
if (total_read < 0) {
ret = total_read;