- Userspace wants to write a string with `len` bytes, not counting the
terminating NULL, so we should allocate `len+1` bytes. It looks like the
current code relied on having a nullbyte directly behind `kern_buff`,
which happens to work reliably as long as `len` isn't one of the kmalloc
size classes.
- strncpy_from_user() is completely wrong here; userspace is giving us a
(not necessarily null-terminated) buffer and its length.
strncpy_from_user() is for cases in which we don't know the length.
- Don't let broken userspace allocate arbitrarily big kmalloc allocations.
Just use memdup_user_nul(), which is designed precisely for things like
this.
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Jolly Shah <jolly.shah@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Add debugfs file to query platform specific data from firmware
using debugfs interface.
Signed-off-by: Rajan Vaja <rajanv@xilinx.com>
Signed-off-by: Jolly Shah <jollys@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Firmware-debug provides debugfs interface to all APIs.
Debugfs can be used to call firmware APIs with required
parameters.
Usage:
* Calling firmware API through debugfs:
# echo "<api-name> <arg1> .. <argn>" > /sys/.../zynqmp-firmware/pm
* Read output of last called firmware API:
# cat /sys/.../zynqmp-firmware/pm
Refer ug1200 for more information on these APIs:
* https://www.xilinx.com/support/documentation/user_guides/ug1200-eemi-api.pdf
Add basic debugfs file to get API version.
Signed-off-by: Rajan Vaja <rajanv@xilinx.com>
Signed-off-by: Jolly Shah <jollys@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
