[PATCH] samples/ftrace: mark my_tramp[12]? global

From: Sami Tolvanen
Date: Fri Nov 13 2020 - 13:34:24 EST


my_tramp[12]? are declared as global functions in C, but they are not
marked global in the inline assembly definition. This mismatch confuses
Clang's Control-Flow Integrity checking. Fix the definitions by adding
.globl.

Signed-off-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx>
---
samples/ftrace/ftrace-direct-modify.c | 2 ++
samples/ftrace/ftrace-direct-too.c | 1 +
samples/ftrace/ftrace-direct.c | 1 +
3 files changed, 4 insertions(+)

diff --git a/samples/ftrace/ftrace-direct-modify.c b/samples/ftrace/ftrace-direct-modify.c
index c13a5bc5095b..5b9a09957c6e 100644
--- a/samples/ftrace/ftrace-direct-modify.c
+++ b/samples/ftrace/ftrace-direct-modify.c
@@ -21,6 +21,7 @@ static unsigned long my_ip = (unsigned long)schedule;
asm (
" .pushsection .text, \"ax\", @progbits\n"
" .type my_tramp1, @function\n"
+" .globl my_tramp1\n"
" my_tramp1:"
" pushq %rbp\n"
" movq %rsp, %rbp\n"
@@ -29,6 +30,7 @@ asm (
" .size my_tramp1, .-my_tramp1\n"
" ret\n"
" .type my_tramp2, @function\n"
+" .globl my_tramp2\n"
" my_tramp2:"
" pushq %rbp\n"
" movq %rsp, %rbp\n"
diff --git a/samples/ftrace/ftrace-direct-too.c b/samples/ftrace/ftrace-direct-too.c
index d5c5022be664..3f0079c9bd6f 100644
--- a/samples/ftrace/ftrace-direct-too.c
+++ b/samples/ftrace/ftrace-direct-too.c
@@ -16,6 +16,7 @@ extern void my_tramp(void *);
asm (
" .pushsection .text, \"ax\", @progbits\n"
" .type my_tramp, @function\n"
+" .globl my_tramp\n"
" my_tramp:"
" pushq %rbp\n"
" movq %rsp, %rbp\n"
diff --git a/samples/ftrace/ftrace-direct.c b/samples/ftrace/ftrace-direct.c
index 63ca06d42c80..a2729d1ef17f 100644
--- a/samples/ftrace/ftrace-direct.c
+++ b/samples/ftrace/ftrace-direct.c
@@ -14,6 +14,7 @@ extern void my_tramp(void *);
asm (
" .pushsection .text, \"ax\", @progbits\n"
" .type my_tramp, @function\n"
+" .globl my_tramp\n"
" my_tramp:"
" pushq %rbp\n"
" movq %rsp, %rbp\n"

base-commit: 585e5b17b92dead8a3aca4e3c9876fbca5f7e0ba
--
2.29.2.299.gdc1121823c-goog