From f2913d006fcdb61719635e093d1b5dd0dafecac7 Mon Sep 17 00:00:00 2001 From: Palmer Dabbelt Date: Tue, 20 Sep 2022 13:00:37 -0700 Subject: [PATCH] RISC-V: Avoid dereferening NULL regs in die() I don't think we can actually die() without a regs pointer, but the compiler was warning about a NULL check after a dereference. It seems prudent to just avoid the possibly-NULL dereference, given that when die()ing the system is already toast so who knows how we got there. Reported-by: kernel test robot Reported-by: Dan Carpenter Reviewed-by: Conor Dooley Link: https://lore.kernel.org/r/20220920200037.6727-1-palmer@rivosinc.com Signed-off-by: Palmer Dabbelt --- arch/riscv/kernel/traps.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c index 635e6ec..f3e96d6 100644 --- a/arch/riscv/kernel/traps.c +++ b/arch/riscv/kernel/traps.c @@ -33,6 +33,7 @@ void die(struct pt_regs *regs, const char *str) { static int die_counter; int ret; + long cause; oops_enter(); @@ -42,11 +43,13 @@ void die(struct pt_regs *regs, const char *str) pr_emerg("%s [#%d]\n", str, ++die_counter); print_modules(); - show_regs(regs); + if (regs) + show_regs(regs); - ret = notify_die(DIE_OOPS, str, regs, 0, regs->cause, SIGSEGV); + cause = regs ? regs->cause : -1; + ret = notify_die(DIE_OOPS, str, regs, 0, cause, SIGSEGV); - if (regs && kexec_should_crash(current)) + if (kexec_should_crash(current)) crash_kexec(regs); bust_spinlocks(0); -- 2.7.4