On Wed, Aug 18, 2021 at 07:29:39PM -0700, Kevin Mitchell wrote:
> When scsi_dispatch_cmd was moved to scsi_lib.c and made static, some
> compilers (i.e., at least gcc 8.4.0) decided to compile this
> inline. This is a problem for lkdtm.ko, which inserted a kprobe
> on this function for the SCSI_DISPATCH_CMD crashpoint.
>
> Move this crashpoint one function up the call chain to
> scsi_queue_rq. Though this is also a static function, it should never be
> inlined because it is assigned as a structure entry. Therefore,
> kprobe_register should always be able to find it.
>
> Fixes: 82042a2cdb55 ("scsi: move scsi_dispatch_cmd to scsi_lib.c")
> Signed-off-by: Kevin Mitchell <kevmitch@xxxxxxxxxx>
Thanks!
Acked-by: Kees Cook <keescook@xxxxxxxxxxxx>
-Kees
> ---
> Documentation/fault-injection/provoke-crashes.rst | 2 +-
> drivers/misc/lkdtm/core.c | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/Documentation/fault-injection/provoke-crashes.rst b/Documentation/fault-injection/provoke-crashes.rst
> index a20ba5d93932..18de17354206 100644
> --- a/Documentation/fault-injection/provoke-crashes.rst
> +++ b/Documentation/fault-injection/provoke-crashes.rst
> @@ -29,7 +29,7 @@ recur_count
> cpoint_name
> Where in the kernel to trigger the action. It can be
> one of INT_HARDWARE_ENTRY, INT_HW_IRQ_EN, INT_TASKLET_ENTRY,
> - FS_DEVRW, MEM_SWAPOUT, TIMERADD, SCSI_DISPATCH_CMD,
> + FS_DEVRW, MEM_SWAPOUT, TIMERADD, SCSI_QUEUE_RQ,
> IDE_CORE_CP, or DIRECT
>
> cpoint_type
> diff --git a/drivers/misc/lkdtm/core.c b/drivers/misc/lkdtm/core.c
> index 9dda87c6b54a..016cb0b150fc 100644
> --- a/drivers/misc/lkdtm/core.c
> +++ b/drivers/misc/lkdtm/core.c
> @@ -82,7 +82,7 @@ static struct crashpoint crashpoints[] = {
> CRASHPOINT("FS_DEVRW", "ll_rw_block"),
> CRASHPOINT("MEM_SWAPOUT", "shrink_inactive_list"),
> CRASHPOINT("TIMERADD", "hrtimer_start"),
> - CRASHPOINT("SCSI_DISPATCH_CMD", "scsi_dispatch_cmd"),
> + CRASHPOINT("SCSI_QUEUE_RQ", "scsi_queue_rq"),
> CRASHPOINT("IDE_CORE_CP", "generic_ide_ioctl"),
> #endif
> };
> --
> 2.32.0
>
--
Kees Cook
