4.4-stable review patch. If anyone has any objections, please let me know.
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From: Heiko Carstens heiko.carstens@de.ibm.com
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@redhat.com Cc: stable@vger.kernel.org # v4.3+ Signed-off-by: Heiko Carstens heiko.carstens@de.ibm.com Signed-off-by: Martin Schwidefsky schwidefsky@de.ibm.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- 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)