diff options
Diffstat (limited to 'arch/x86/kernel/dumpstack.c')
| -rw-r--r-- | arch/x86/kernel/dumpstack.c | 27 |
1 files changed, 17 insertions, 10 deletions
diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c index b037cfa7c0c5..7401cc12c3cc 100644 --- a/arch/x86/kernel/dumpstack.c +++ b/arch/x86/kernel/dumpstack.c @@ -71,6 +71,22 @@ static void printk_stack_address(unsigned long address, int reliable, printk("%s %s%pB\n", log_lvl, reliable ? "" : "? ", (void *)address); } +static int copy_code(struct pt_regs *regs, u8 *buf, unsigned long src, + unsigned int nbytes) +{ + if (!user_mode(regs)) + return copy_from_kernel_nofault(buf, (u8 *)src, nbytes); + + /* + * Make sure userspace isn't trying to trick us into dumping kernel + * memory by pointing the userspace instruction pointer at it. + */ + if (__chk_range_not_ok(src, nbytes, TASK_SIZE_MAX)) + return -EINVAL; + + return copy_from_user_nmi(buf, (void __user *)src, nbytes); +} + /* * There are a couple of reasons for the 2/3rd prologue, courtesy of Linus: * @@ -97,17 +113,8 @@ void show_opcodes(struct pt_regs *regs, const char *loglvl) #define OPCODE_BUFSIZE (PROLOGUE_SIZE + 1 + EPILOGUE_SIZE) u8 opcodes[OPCODE_BUFSIZE]; unsigned long prologue = regs->ip - PROLOGUE_SIZE; - bool bad_ip; - - /* - * Make sure userspace isn't trying to trick us into dumping kernel - * memory by pointing the userspace instruction pointer at it. - */ - bad_ip = user_mode(regs) && - __chk_range_not_ok(prologue, OPCODE_BUFSIZE, TASK_SIZE_MAX); - if (bad_ip || copy_from_kernel_nofault(opcodes, (u8 *)prologue, - OPCODE_BUFSIZE)) { + if (copy_code(regs, opcodes, prologue, sizeof(opcodes))) { printk("%sCode: Bad RIP value.\n", loglvl); } else { printk("%sCode: %" __stringify(PROLOGUE_SIZE) "ph <%02x> %" |