4fc19708b1
To prevent improper use of the PTEs that are used for text patching, the next patches will use a temporary mm struct. Initailize it by copying the init mm. The address that will be used for patching is taken from the lower area that is usually used for the task memory. Doing so prevents the need to frequently synchronize the temporary-mm (e.g., when BPF programs are installed), since different PGDs are used for the task memory. Finally, randomize the address of the PTEs to harden against exploits that use these PTEs. Suggested-by: Andy Lutomirski <luto@kernel.org> Tested-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Nadav Amit <namit@vmware.com> Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Rik van Riel <riel@surriel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: akpm@linux-foundation.org Cc: ard.biesheuvel@linaro.org Cc: deneen.t.dock@intel.com Cc: kernel-hardening@lists.openwall.com Cc: kristen@linux.intel.com Cc: linux_dti@icloud.com Cc: will.deacon@arm.com Link: https://lkml.kernel.org/r/20190426232303.28381-8-nadav.amit@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org> |
||
|---|---|---|
| .. | ||
| Kconfig | ||
| Makefile | ||
| calibrate.c | ||
| do_mounts.c | ||
| do_mounts.h | ||
| do_mounts_initrd.c | ||
| do_mounts_md.c | ||
| do_mounts_rd.c | ||
| init_task.c | ||
| initramfs.c | ||
| main.c | ||
| noinitramfs.c | ||
| version.c | ||