On Mon, Jan 28, 2019 at 11:08:54AM +0800, Yang Yingliang wrote:
> When we excute the following commands, we got oops
> rmmod ipmi_si
> cat /proc/ioports
>
snip..
>
> If io_setup is called successful in try_smi_init() but try_smi_init()
> goes out_err before calling ipmi_register_smi(), so ipmi_unregister_smi()
> will not be called while removing module. It leads to the resource that
> allocated in io_setup() can not be freed, but the name(DEVICE_NAME) of
> resource is freed while removing the module. It causes use-after-free
> when cat /proc/ioports.
>
> Fix this by calling io_cleanup() while try_smi_init() goes to out_err.
> and don't call io_cleanup() until io_setup() returns successful to avoid
> warning prints.
Thanks a bunch for working on this. Fix is in my next tree now, if it
is stable in there then I will send up to Linus.
-corey
>
> Fixes: 93c303d2045b ("ipmi_si: Clean up shutdown a bit")
> Cc: stable@xxxxxxxxxxxxxxx
> Reported-by: NuoHan Qiao <qiaonuohan@xxxxxxxxxx>
> Suggested-by: Corey Minyard <cminyard@xxxxxxxxxx>
> Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx>
> ---
> drivers/char/ipmi/ipmi_si_intf.c | 5 +++++
> drivers/char/ipmi/ipmi_si_mem_io.c | 5 +++--
> drivers/char/ipmi/ipmi_si_port_io.c | 5 +++--
> 3 files changed, 11 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c
> index dc8603d..f1b9fda 100644
> --- a/drivers/char/ipmi/ipmi_si_intf.c
> +++ b/drivers/char/ipmi/ipmi_si_intf.c
> @@ -2085,6 +2085,11 @@ static int try_smi_init(struct smi_info *new_smi)
> WARN_ON(new_smi->io.dev->init_name != NULL);
>
> out_err:
> + if (rv && new_smi->io.io_cleanup) {
> + new_smi->io.io_cleanup(&new_smi->io);
> + new_smi->io.io_cleanup = NULL;
> + }
> +
> kfree(init_name);
> return rv;
> }
> diff --git a/drivers/char/ipmi/ipmi_si_mem_io.c b/drivers/char/ipmi/ipmi_si_mem_io.c
> index fd0ec8d..7558361 100644
> --- a/drivers/char/ipmi/ipmi_si_mem_io.c
> +++ b/drivers/char/ipmi/ipmi_si_mem_io.c
> @@ -81,8 +81,6 @@ int ipmi_si_mem_setup(struct si_sm_io *io)
> if (!addr)
> return -ENODEV;
>
> - io->io_cleanup = mem_cleanup;
> -
> /*
> * Figure out the actual readb/readw/readl/etc routine to use based
> * upon the register size.
> @@ -141,5 +139,8 @@ int ipmi_si_mem_setup(struct si_sm_io *io)
> mem_region_cleanup(io, io->io_size);
> return -EIO;
> }
> +
> + io->io_cleanup = mem_cleanup;
> +
> return 0;
> }
> diff --git a/drivers/char/ipmi/ipmi_si_port_io.c b/drivers/char/ipmi/ipmi_si_port_io.c
> index ef6dffc..03924c3 100644
> --- a/drivers/char/ipmi/ipmi_si_port_io.c
> +++ b/drivers/char/ipmi/ipmi_si_port_io.c
> @@ -68,8 +68,6 @@ int ipmi_si_port_setup(struct si_sm_io *io)
> if (!addr)
> return -ENODEV;
>
> - io->io_cleanup = port_cleanup;
> -
> /*
> * Figure out the actual inb/inw/inl/etc routine to use based
> * upon the register size.
> @@ -109,5 +107,8 @@ int ipmi_si_port_setup(struct si_sm_io *io)
> return -EIO;
> }
> }
> +
> + io->io_cleanup = port_cleanup;
> +
> return 0;
> }
> --
> 1.8.3
>
>
