2017-12-12 02:16:44

by Jia-Ju Bai

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Subject: [BUG] drivers/scsi/dpt_i2o: a possible sleep-in-atomic bug in adpt_i2o_post_this

According to drivers/scsi/dpt_i2o.c, the kernel module may sleep under a
spinlock.
The function call paths are:
adpt_abort (acquire the spinlock)
adpt_i2o_post_wait
adpt_i2o_post_this
schedule_timeout_uninterruptible--> may sleep

adpt_device_reset (acquire the spinlock)
adpt_i2o_post_wait
adpt_i2o_post_this
schedule_timeout_uninterruptible--> may sleep

adpt_bus_reset (acquire the spinlock)
adpt_i2o_post_wait
adpt_i2o_post_this
schedule_timeout_uninterruptible--> may sleep

A possible fixing is to replace "schedule_timeout_uninterruptible" with
"mdelay".
If this fixing is correct, I can send a patch.
This possible bug is found by my static analysis tool (DSAC) and checked
by my code review.


Thanks,
Jia-Ju Bai