ping On 2020/10/16 10:31, Xiaoming Ni wrote:
Printing raw pointer values in backtraces has potential security implications and are of questionable value anyway.This patch follows x86 and arm64's lead and removes the "Exception stack:" dump from kernel backtraces: commit a25ffd3a6302a6 ("arm64: traps: Don't print stack or raw PC/LR values in backtraces") commit bb5e5ce545f203 ("x86/dumpstack: Remove kernel text addresses from stack dump") Signed-off-by: Xiaoming Ni <nixiaom...@huawei.com> ------- v2: Delete [<hex numbers>] from the stack according to the email discussion in patch V1, Other information processing will be discussed in subsequent patches. v1: https://lore.kernel.org/lkml/20201009075957.110017-1-nixiaom...@huawei.com/ 1. Don't print stack or raw PC/LR hex values in backtraces 2. Don't print stack mem in backtraces 3. if (!panic_on_oops), Don't print stack mem in __die() --- arch/arm/kernel/process.c | 3 +-- arch/arm/kernel/traps.c | 4 ++-- 2 files changed, 3 insertions(+), 4 deletions(-) diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 8e6ace03e960..71c9e5597d39 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -121,8 +121,7 @@ void __show_regs(struct pt_regs *regs)printk("PC is at %pS\n", (void *)instruction_pointer(regs));printk("LR is at %pS\n", (void *)regs->ARM_lr); - printk("pc : [<%08lx>] lr : [<%08lx>] psr: %08lx\n", - regs->ARM_pc, regs->ARM_lr, regs->ARM_cpsr); + printk("psr: %08lx\n", regs->ARM_cpsr); printk("sp : %08lx ip : %08lx fp : %08lx\n", regs->ARM_sp, regs->ARM_ip, regs->ARM_fp); printk("r10: %08lx r9 : %08lx r8 : %08lx\n", diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c index 17d5a785df28..911bbf164875 100644 --- a/arch/arm/kernel/traps.c +++ b/arch/arm/kernel/traps.c @@ -68,8 +68,8 @@ void dump_backtrace_entry(unsigned long where, unsigned long from, unsigned long end = frame + 4 + sizeof(struct pt_regs);#ifdef CONFIG_KALLSYMS- printk("%s[<%08lx>] (%ps) from [<%08lx>] (%pS)\n", - loglvl, where, (void *)where, from, (void *)from); + printk("%s (%ps) from (%pS)\n", + loglvl, (void *)where, (void *)from); #else printk("%sFunction entered at [<%08lx>] from [<%08lx>]\n", loglvl, where, from);
