On Wed, 6 May 2020 10:59:55 +0530 Srikar Dronamraju <[email protected]> wrote:
> * 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 Oleg, Srikar and Sven. As this is in the kernel/events/ directory, I'm guessing it should be taken through the tip tree? -- Steve
