4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
commit 783c3b53b9506db3e05daacfe34e0287eebb09d8 upstream.
Implement s390 specific arch_uretprobe_is_alive() to avoid SIGSEGVs
observed with uretprobes in combination with setjmp/longjmp.
See commit 2dea1d9c38e4 ("powerpc/uprobes: Implement
arch_uretprobe_is_alive()") for more details.
With this implemented all test cases referenced in the above commit
pass.
Reported-by: Ziqian SUN <zsun@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> # v4.3+
Signed-off-by: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/s390/kernel/uprobes.c | 9 +++++++++
1 file changed, 9 insertions(+)
--- a/arch/s390/kernel/uprobes.c
+++ b/arch/s390/kernel/uprobes.c
@@ -147,6 +147,15 @@ unsigned long arch_uretprobe_hijack_retu
return orig;
}
+bool arch_uretprobe_is_alive(struct return_instance *ret, enum rp_check ctx,
+ struct pt_regs *regs)
+{
+ if (ctx == RP_CHECK_CHAIN_CALL)
+ return user_stack_pointer(regs) <= ret->stack;
+ else
+ return user_stack_pointer(regs) < ret->stack;
+}
+
/* Instruction Emulation */
static void adjust_psw_addr(psw_t *psw, unsigned long len)