summaryrefslogtreecommitdiff
path: root/drivers/misc/lkdtm/perms.c
diff options
context:
space:
mode:
authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2025-05-02 08:59:33 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2025-05-02 08:59:33 +0300
commitb004c046df92c429202e899f3f117814a5eb02d3 (patch)
tree1ac2b86f3a22d67776025c40840f522e269558e3 /drivers/misc/lkdtm/perms.c
parentc04005ef3576893e2db315d9ea2cfa4cf88b2c05 (diff)
parentc72e4daa7ab2814e402f2b67dd1681ea4db446af (diff)
downloadlinux-rolling-lts.tar.xz
Merge v6.12.26linux-rolling-lts
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/misc/lkdtm/perms.c')
-rw-r--r--drivers/misc/lkdtm/perms.c14
1 files changed, 11 insertions, 3 deletions
diff --git a/drivers/misc/lkdtm/perms.c b/drivers/misc/lkdtm/perms.c
index 5b861dbff27e..6c24426104ba 100644
--- a/drivers/misc/lkdtm/perms.c
+++ b/drivers/misc/lkdtm/perms.c
@@ -29,6 +29,13 @@ static const unsigned long rodata = 0xAA55AA55;
static unsigned long ro_after_init __ro_after_init = 0x55AA5500;
/*
+ * This is a pointer to do_nothing() which is initialized at runtime rather
+ * than build time to avoid objtool IBT validation warnings caused by an
+ * inlined unrolled memcpy() in execute_location().
+ */
+static void __ro_after_init *do_nothing_ptr;
+
+/*
* This just returns to the caller. It is designed to be copied into
* non-executable memory regions.
*/
@@ -65,13 +72,12 @@ static noinline __nocfi void execute_location(void *dst, bool write)
{
void (*func)(void);
func_desc_t fdesc;
- void *do_nothing_text = dereference_function_descriptor(do_nothing);
- pr_info("attempting ok execution at %px\n", do_nothing_text);
+ pr_info("attempting ok execution at %px\n", do_nothing_ptr);
do_nothing();
if (write == CODE_WRITE) {
- memcpy(dst, do_nothing_text, EXEC_SIZE);
+ memcpy(dst, do_nothing_ptr, EXEC_SIZE);
flush_icache_range((unsigned long)dst,
(unsigned long)dst + EXEC_SIZE);
}
@@ -267,6 +273,8 @@ static void lkdtm_ACCESS_NULL(void)
void __init lkdtm_perms_init(void)
{
+ do_nothing_ptr = dereference_function_descriptor(do_nothing);
+
/* Make sure we can write to __ro_after_init values during __init */
ro_after_init |= 0xAA;
}