Messages in this thread Patch in this message | | | From | Nathan Chancellor <> | Subject | [PATCH] qemu_fw_cfg: Make fw_cfg_rev_attr a proper kobj_attribute | Date | Thu, 11 Feb 2021 12:42:58 -0700 |
| |
fw_cfg_showrev() is called by an indirect call in kobj_attr_show(), which violates clang's CFI checking because fw_cfg_showrev()'s second parameter is 'struct attribute', whereas the ->show() member of 'struct kobj_structure' expects the second parameter to be of type 'struct kobj_attribute'.
$ cat /sys/firmware/qemu_fw_cfg/rev 3
$ dmesg | grep "CFI failure" [ 26.016832] CFI failure (target: fw_cfg_showrev+0x0/0x8):
Fix this by converting fw_cfg_rev_attr to 'struct kobj_attribute' where this would have been caught automatically by the incompatible pointer types compiler warning. Update fw_cfg_showrev() accordingly.
Fixes: 75f3e8e47f38 ("firmware: introduce sysfs driver for QEMU's fw_cfg device") Link: https://github.com/ClangBuiltLinux/linux/issues/1299 Signed-off-by: Nathan Chancellor <nathan@kernel.org> --- drivers/firmware/qemu_fw_cfg.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-)
diff --git a/drivers/firmware/qemu_fw_cfg.c b/drivers/firmware/qemu_fw_cfg.c index 0078260fbabe..172c751a4f6c 100644 --- a/drivers/firmware/qemu_fw_cfg.c +++ b/drivers/firmware/qemu_fw_cfg.c @@ -299,15 +299,13 @@ static int fw_cfg_do_platform_probe(struct platform_device *pdev) return 0; } -static ssize_t fw_cfg_showrev(struct kobject *k, struct attribute *a, char *buf) +static ssize_t fw_cfg_showrev(struct kobject *k, struct kobj_attribute *a, + char *buf) { return sprintf(buf, "%u\n", fw_cfg_rev); } -static const struct { - struct attribute attr; - ssize_t (*show)(struct kobject *k, struct attribute *a, char *buf); -} fw_cfg_rev_attr = { +static const struct kobj_attribute fw_cfg_rev_attr = { .attr = { .name = "rev", .mode = S_IRUSR }, .show = fw_cfg_showrev, }; base-commit: 92bf22614b21a2706f4993b278017e437f7785b3 -- 2.30.1
| |