4.8-stable review patch. If anyone has any objections, please let me know.
------------------ From: Al Viro <[email protected]> commit 7798bf2140ebcc36eafec6a4194fffd8d585d471 upstream. On faulting sigreturn we do get SIGSEGV, all right, but anything we'd put into pt_regs could end up in the coredump. And since __copy_from_user() never zeroed on arc, we'd better bugger off on its failure without copying random uninitialized bits of kernel stack into pt_regs... Signed-off-by: Al Viro <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- arch/arc/kernel/signal.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/arch/arc/kernel/signal.c +++ b/arch/arc/kernel/signal.c @@ -107,13 +107,13 @@ static int restore_usr_regs(struct pt_re struct user_regs_struct uregs; err = __copy_from_user(&set, &sf->uc.uc_sigmask, sizeof(set)); - if (!err) - set_current_blocked(&set); - err |= __copy_from_user(&uregs.scratch, &(sf->uc.uc_mcontext.regs.scratch), sizeof(sf->uc.uc_mcontext.regs.scratch)); + if (err) + return err; + set_current_blocked(&set); regs->bta = uregs.scratch.bta; regs->lp_start = uregs.scratch.lp_start; regs->lp_end = uregs.scratch.lp_end; @@ -138,7 +138,7 @@ static int restore_usr_regs(struct pt_re regs->r0 = uregs.scratch.r0; regs->sp = uregs.scratch.sp; - return err; + return 0; } static inline int is_do_ss_needed(unsigned int magic)
