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Subject[PATCH] m68k: use get_kernel_nofault in show_registers
Date
Use the proper get_kernel_nofault helper to access an unsafe kernel
pointer without faulting instead of playing with set_fs and get_user.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
arch/m68k/kernel/traps.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/arch/m68k/kernel/traps.c b/arch/m68k/kernel/traps.c
index df6fc782754f73..c265355fa244d4 100644
--- a/arch/m68k/kernel/traps.c
+++ b/arch/m68k/kernel/traps.c
@@ -846,7 +846,6 @@ static void show_trace(unsigned long *stack, const char *loglvl)
void show_registers(struct pt_regs *regs)
{
struct frame *fp = (struct frame *)regs;
- mm_segment_t old_fs = get_fs();
u16 c, *cp;
unsigned long addr;
int i;
@@ -919,10 +918,9 @@ void show_registers(struct pt_regs *regs)
show_stack(NULL, (unsigned long *)addr, KERN_INFO);

pr_info("Code:");
- set_fs(KERNEL_DS);
cp = (u16 *)regs->pc;
for (i = -8; i < 16; i++) {
- if (get_user(c, cp + i) && i >= 0) {
+ if (get_kernel_nofault(c, cp + i) && i >= 0) {
pr_cont(" Bad PC value.");
break;
}
@@ -931,7 +929,6 @@ void show_registers(struct pt_regs *regs)
else
pr_cont(" <%04x>", c);
}
- set_fs(old_fs);
pr_cont("\n");
}

--
2.27.0
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