[PATCH 4.4 34/93] MIPS: fix uretprobe implementation

From: Greg Kroah-Hartman
Date: Thu Oct 06 2016 - 04:54:33 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: Marcin Nowakowski <marcin.nowakowski@xxxxxxxxxx>

commit db06068a4fd44a57b642b369d2a295b8448f6b65 upstream.

arch_uretprobe_hijack_return_addr should replace the return address for
a call with a trampoline address.

Signed-off-by: Marcin Nowakowski <marcin.nowakowski@xxxxxxxxxx>
Fixes: 40e084a506eb ('MIPS: Add uprobes support.')
Cc: linux-mips@xxxxxxxxxxxxxx
Patchwork: https://patchwork.linux-mips.org/patch/14298/
Signed-off-by: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/mips/kernel/uprobes.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/mips/kernel/uprobes.c
+++ b/arch/mips/kernel/uprobes.c
@@ -257,7 +257,7 @@ unsigned long arch_uretprobe_hijack_retu
ra = regs->regs[31];

/* Replace the return address with the trampoline address */
- regs->regs[31] = ra;
+ regs->regs[31] = trampoline_vaddr;

return ra;
}