tree ab0b3311333669d4363b7219d678adc0569a8ad6
parent ea998a663879047e949988b44f754e2c899b0e10
author Bart Van Assche <bvanassche@acm.org> 1400574821 +0200
committer chrmhoffmann <chrmhoffmann@gmail.com> 1586074826 +0200

IB/umad: Fix error handling

commit 8ec0a0e6b58218bdc1db91dd70ebfcd6ad8dd6cd upstream.

Avoid leaking a kref count in ib_umad_open() if port->ib_dev == NULL
or if nonseekable_open() fails.

Avoid leaking a kref count, that sm_sem is kept down and also that the
IB_PORT_SM capability mask is not cleared in ib_umad_sm_open() if
nonseekable_open() fails.

Since container_of() never returns NULL, remove the code that tests
whether container_of() returns NULL.

Moving the kref_get() call from the start of ib_umad_*open() to the
end is safe since it is the responsibility of the caller of these
functions to ensure that the cdev pointer remains valid until at least
when these functions return.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>

[ydroneaud@opteya.com: rework a bit to reduce the amount of code changed]

Signed-off-by: Yann Droneaud <ydroneaud@opteya.com>

[ nonseekable_open() can't actually fail, but....  - Roland ]

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>