96ae522795
This allows user memory to be written to during the course of a kprobe. It shouldn't be used to implement any kind of security mechanism because of TOC-TOU attacks, but rather to debug, divert, and manipulate execution of semi-cooperative processes. Although it uses probe_kernel_write, we limit the address space the probe can write into by checking the space with access_ok. We do this as opposed to calling copy_to_user directly, in order to avoid sleeping. In addition we ensure the threads's current fs / segment is USER_DS and the thread isn't exiting nor a kernel thread. Given this feature is meant for experiments, and it has a risk of crashing the system, and running programs, we print a warning on when a proglet that attempts to use this helper is installed, along with the pid and process name. Signed-off-by: Sargun Dhillon <sargun@sargun.me> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> |
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| .. | ||
| bpf | ||
| configfs | ||
| connector | ||
| hidraw | ||
| hw_breakpoint | ||
| kdb | ||
| kfifo | ||
| kobject | ||
| kprobes | ||
| livepatch | ||
| pktgen | ||
| rpmsg | ||
| seccomp | ||
| trace_events | ||
| uhid | ||
| v4l | ||
| Kconfig | ||
| Makefile | ||