* Oleg Nesterov <[email protected]> [2020-05-04 18:47:25]: > uprobe_write_opcode() must not cross page boundary; prepare_uprobe() > relies on arch_uprobe_analyze_insn() which should validate "vaddr" but > some architectures (csky, s390, and sparc) don't do this. > > We can remove the BUG_ON() check in prepare_uprobe() and validate the > offset early in __uprobe_register(). The new IS_ALIGNED() check matches > the alignment check in arch_prepare_kprobe() on supported architectures, > so I think that all insns must be aligned to UPROBE_SWBP_INSN_SIZE. > > Another problem is __update_ref_ctr() which was wrong from the very > beginning, it can read/write outside of kmap'ed page unless "vaddr" is > aligned to sizeof(short), __uprobe_register() should check this too. > > Cc: [email protected] > Reported-by: Linus Torvalds <[email protected]> > Suggested-by: Linus Torvalds <[email protected]> > Signed-off-by: Oleg Nesterov <[email protected]>
Thanks Oleg. Looks good to me. Reviewed-by: Srikar Dronamraju <[email protected]> > --- -- Thanks and Regards Srikar Dronamraju
