x86/dumpstack: Add a show_ip() function

... which shows the Instruction Pointer along with the insn bytes around
it. Use it whenever rIP is printed. Drop the rIP < PAGE_OFFSET check since
probe_kernel_read() can handle any address properly.

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Link: https://lkml.kernel.org/r/20180417161124.5294-8-bp@alien8.de
This commit is contained in:
Borislav Petkov 2018-04-17 18:11:22 +02:00 committed by Thomas Gleixner
parent ba54d856a9
commit 7cccf0725c
3 changed files with 17 additions and 15 deletions

View File

@ -112,4 +112,5 @@ static inline unsigned long caller_frame_pointer(void)
}
void show_opcodes(u8 *rip, const char *loglvl);
void show_ip(struct pt_regs *regs, const char *loglvl);
#endif /* _ASM_X86_STACKTRACE_H */

View File

@ -94,9 +94,19 @@ void show_opcodes(u8 *rip, const char *loglvl)
pr_cont("\n");
}
void show_ip(struct pt_regs *regs, const char *loglvl)
{
#ifdef CONFIG_X86_32
printk("%sEIP: %pS\n", loglvl, (void *)regs->ip);
#else
printk("%sRIP: %04x:%pS\n", loglvl, (int)regs->cs, (void *)regs->ip);
#endif
show_opcodes((u8 *)regs->ip, loglvl);
}
void show_iret_regs(struct pt_regs *regs)
{
printk(KERN_DEFAULT "RIP: %04x:%pS\n", (int)regs->cs, (void *)regs->ip);
show_ip(regs, KERN_DEFAULT);
printk(KERN_DEFAULT "RSP: %04x:%016lx EFLAGS: %08lx", (int)regs->ss,
regs->sp, regs->flags);
}
@ -392,15 +402,8 @@ void show_regs(struct pt_regs *regs)
__show_regs(regs, all);
/*
* When in-kernel, we also print out the stack and code at the
* time of the fault..
* When in-kernel, we also print out the stack at the time of the fault..
*/
if (!user_mode(regs)) {
if (!user_mode(regs))
show_trace_log_lvl(current, regs, NULL, KERN_DEFAULT);
if (regs->ip < PAGE_OFFSET)
printk(KERN_DEFAULT "Code: Bad RIP value.\n");
else
show_opcodes((u8 *)regs->ip, KERN_DEFAULT);
}
}

View File

@ -76,16 +76,14 @@ void __show_regs(struct pt_regs *regs, int all)
savesegment(gs, gs);
}
printk(KERN_DEFAULT "EIP: %pS\n", (void *)regs->ip);
printk(KERN_DEFAULT "EFLAGS: %08lx CPU: %d\n", regs->flags,
raw_smp_processor_id());
show_ip(regs, KERN_DEFAULT);
printk(KERN_DEFAULT "EAX: %08lx EBX: %08lx ECX: %08lx EDX: %08lx\n",
regs->ax, regs->bx, regs->cx, regs->dx);
printk(KERN_DEFAULT "ESI: %08lx EDI: %08lx EBP: %08lx ESP: %08lx\n",
regs->si, regs->di, regs->bp, sp);
printk(KERN_DEFAULT " DS: %04x ES: %04x FS: %04x GS: %04x SS: %04x\n",
(u16)regs->ds, (u16)regs->es, (u16)regs->fs, gs, ss);
printk(KERN_DEFAULT "DS: %04x ES: %04x FS: %04x GS: %04x SS: %04x EFLAGS: %08lx\n",
(u16)regs->ds, (u16)regs->es, (u16)regs->fs, gs, ss, regs->flags);
if (!all)
return;