From daa559570d4b81e98e5a77a5c0f2a88879a9f245 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Thu, 1 Feb 2024 18:28:06 +0100 Subject: ARM: 9349/1: unwind: Add missing "Call trace:" line Every other architecture in Linux includes the line "Call trace:" before backtraces. In some cases ARM would print "Backtrace:", but this was only via 1 specific call path, and wasn't included in CPU Oops nor things like KASAN, UBSAN, etc that called dump_stack(). Regularize this line so CI systems and other things (like LKDTM) that depend on parsing "Call trace:" out of dmesg will see it for ARM. Before this patch: UBSAN: array-index-out-of-bounds in ../drivers/misc/lkdtm/bugs.c:376:16 index 8 is out of range for type 'char [8]' CPU: 0 PID: 1402 Comm: cat Not tainted 6.7.0-rc2 #1 Hardware name: Generic DT based system dump_backtrace from show_stack+0x20/0x24 r7:00000042 r6:00000000 r5:60070013 r4:80cf5d7c show_stack from dump_stack_lvl+0x88/0x98 dump_stack_lvl from dump_stack+0x18/0x1c r7:00000042 r6:00000008 r5:00000008 r4:80fab118 dump_stack from ubsan_epilogue+0x10/0x3c ubsan_epilogue from __ubsan_handle_out_of_bounds+0x80/0x84 ... After this patch: UBSAN: array-index-out-of-bounds in ../drivers/misc/lkdtm/bugs.c:376:16 index 8 is out of range for type 'char [8]' CPU: 0 PID: 1402 Comm: cat Not tainted 6.7.0-rc2 #1 Hardware name: Generic DT based system Call trace: dump_backtrace from show_stack+0x20/0x24 r7:00000042 r6:00000000 r5:60070013 r4:80cf5d7c show_stack from dump_stack_lvl+0x88/0x98 dump_stack_lvl from dump_stack+0x18/0x1c r7:00000042 r6:00000008 r5:00000008 r4:80fab118 dump_stack from ubsan_epilogue+0x10/0x3c ubsan_epilogue from __ubsan_handle_out_of_bounds+0x80/0x84 ... Link: https://lore.kernel.org/r/20240110215554.work.460-kees@kernel.org Reported-by: Mark Brown Cc: Ard Biesheuvel Cc: Arnd Bergmann Cc: Linus Walleij Cc: Vladimir Murzin Cc: Zhen Lei Cc: Keith Packard Cc: Haibo Li Cc: Reviewed-by: Mark Brown Reviewed-by: Linus Walleij Reviewed-by: AngeloGioacchino Del Regno Signed-off-by: Kees Cook Signed-off-by: Russell King (Oracle) --- arch/arm/kernel/traps.c | 2 +- arch/arm/kernel/unwind.c | 2 ++ 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c index 3bad79db5d6e..72c82a4d63ac 100644 --- a/arch/arm/kernel/traps.c +++ b/arch/arm/kernel/traps.c @@ -220,7 +220,7 @@ void dump_backtrace(struct pt_regs *regs, struct task_struct *tsk, unsigned int fp, mode; int ok = 1; - printk("%sBacktrace: ", loglvl); + printk("%sCall trace: ", loglvl); if (!tsk) tsk = current; diff --git a/arch/arm/kernel/unwind.c b/arch/arm/kernel/unwind.c index 9d2192156087..f60547dadc93 100644 --- a/arch/arm/kernel/unwind.c +++ b/arch/arm/kernel/unwind.c @@ -524,6 +524,8 @@ void unwind_backtrace(struct pt_regs *regs, struct task_struct *tsk, { struct stackframe frame; + printk("%sCall trace: ", loglvl); + pr_debug("%s(regs = %p tsk = %p)\n", __func__, regs, tsk); if (!tsk) -- cgit v1.2.3