mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-05 18:14:07 +08:00
x86: Avoid pr_cont() in show_opcodes()
If concurrent printk() messages are emitted, then pr_cont() is making it extremly hard to decode which part of the output belongs to what. See the convoluted example at: https://syzkaller.appspot.com/text?tag=CrashReport&x=139d342c400000 Avoid this by using a proper prefix for each line and by using %ph format in show_opcodes() which emits the 'Code:' line in one go. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: joe@perches.com Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@suse.de> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lkml.kernel.org/r/1532009278-5953-1-git-send-email-penguin-kernel@I-love.SAKURA.ne.jp
This commit is contained in:
parent
9d3cce1e8b
commit
8e974b3b8e
@ -22,8 +22,6 @@
|
||||
#include <asm/stacktrace.h>
|
||||
#include <asm/unwind.h>
|
||||
|
||||
#define OPCODE_BUFSIZE 64
|
||||
|
||||
int panic_on_unrecovered_nmi;
|
||||
int panic_on_io_nmi;
|
||||
static int die_counter;
|
||||
@ -93,26 +91,18 @@ static void printk_stack_address(unsigned long address, int reliable,
|
||||
*/
|
||||
void show_opcodes(u8 *rip, const char *loglvl)
|
||||
{
|
||||
unsigned int code_prologue = OPCODE_BUFSIZE * 2 / 3;
|
||||
#define PROLOGUE_SIZE 42
|
||||
#define EPILOGUE_SIZE 21
|
||||
#define OPCODE_BUFSIZE (PROLOGUE_SIZE + 1 + EPILOGUE_SIZE)
|
||||
u8 opcodes[OPCODE_BUFSIZE];
|
||||
u8 *ip;
|
||||
int i;
|
||||
|
||||
printk("%sCode: ", loglvl);
|
||||
|
||||
ip = (u8 *)rip - code_prologue;
|
||||
if (probe_kernel_read(opcodes, ip, OPCODE_BUFSIZE)) {
|
||||
pr_cont("Bad RIP value.\n");
|
||||
return;
|
||||
if (probe_kernel_read(opcodes, rip - PROLOGUE_SIZE, OPCODE_BUFSIZE)) {
|
||||
printk("%sCode: Bad RIP value.\n", loglvl);
|
||||
} else {
|
||||
printk("%sCode: %" __stringify(PROLOGUE_SIZE) "ph <%02x> %"
|
||||
__stringify(EPILOGUE_SIZE) "ph\n", loglvl, opcodes,
|
||||
opcodes[PROLOGUE_SIZE], opcodes + PROLOGUE_SIZE + 1);
|
||||
}
|
||||
|
||||
for (i = 0; i < OPCODE_BUFSIZE; i++, ip++) {
|
||||
if (ip == rip)
|
||||
pr_cont("<%02x> ", opcodes[i]);
|
||||
else
|
||||
pr_cont("%02x ", opcodes[i]);
|
||||
}
|
||||
pr_cont("\n");
|
||||
}
|
||||
|
||||
void show_ip(struct pt_regs *regs, const char *loglvl)
|
||||
|
Loading…
Reference in New Issue
Block a user