]> git.proxmox.com Git - mirror_ubuntu-eoan-kernel.git/commitdiff
stackleak: Mark stackleak_track_stack() as notrace
authorAnders Roxell <anders.roxell@linaro.org>
Fri, 30 Nov 2018 15:08:59 +0000 (16:08 +0100)
committerKees Cook <keescook@chromium.org>
Thu, 6 Dec 2018 03:31:44 +0000 (19:31 -0800)
Function graph tracing recurses into itself when stackleak is enabled,
causing the ftrace graph selftest to run for up to 90 seconds and
trigger the softlockup watchdog.

Breakpoint 2, ftrace_graph_caller () at ../arch/arm64/kernel/entry-ftrace.S:200
200             mcount_get_lr_addr        x0    //     pointer to function's saved lr
(gdb) bt
\#0  ftrace_graph_caller () at ../arch/arm64/kernel/entry-ftrace.S:200
\#1  0xffffff80081d5280 in ftrace_caller () at ../arch/arm64/kernel/entry-ftrace.S:153
\#2  0xffffff8008555484 in stackleak_track_stack () at ../kernel/stackleak.c:106
\#3  0xffffff8008421ff8 in ftrace_ops_test (ops=0xffffff8009eaa840 <graph_ops>, ip=18446743524091297036, regs=<optimized out>) at ../kernel/trace/ftrace.c:1507
\#4  0xffffff8008428770 in __ftrace_ops_list_func (regs=<optimized out>, ignored=<optimized out>, parent_ip=<optimized out>, ip=<optimized out>) at ../kernel/trace/ftrace.c:6286
\#5  ftrace_ops_no_ops (ip=18446743524091297036, parent_ip=18446743524091242824) at ../kernel/trace/ftrace.c:6321
\#6  0xffffff80081d5280 in ftrace_caller () at ../arch/arm64/kernel/entry-ftrace.S:153
\#7  0xffffff800832fd10 in irq_find_mapping (domain=0xffffffc03fc4bc80, hwirq=27) at ../kernel/irq/irqdomain.c:876
\#8  0xffffff800832294c in __handle_domain_irq (domain=0xffffffc03fc4bc80, hwirq=27, lookup=true, regs=0xffffff800814b840) at ../kernel/irq/irqdesc.c:650
\#9  0xffffff80081d52b4 in ftrace_graph_caller () at ../arch/arm64/kernel/entry-ftrace.S:205

Rework so we mark stackleak_track_stack as notrace

Co-developed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
kernel/stackleak.c

index 08cb57eed3893d191b53d7e8b46a8d5ae4ba2747..b193a59fc05b0aae11a8c3173f5e1aca099ff113 100644 (file)
@@ -104,7 +104,7 @@ asmlinkage void notrace stackleak_erase(void)
 }
 NOKPROBE_SYMBOL(stackleak_erase);
 
-void __used stackleak_track_stack(void)
+void __used notrace stackleak_track_stack(void)
 {
        /*
         * N.B. stackleak_erase() fills the kernel stack with the poison value,