[PATCH 2/5] modpost: fix ishtp MODULE_DEVICE_TABLE built on big endian host

From: Masahiro Yamada
Date: Sat Oct 07 2023 - 13:05:22 EST


When MODULE_DEVICE_TABLE(ishtp, ) is built on a host with a different
endianness from the target architecture, it results in an incorrect
MODULE_ALIAS().

For example, see a case where drivers/platform/x86/intel/ishtp_eclite.c
is built as a module.

If you build it on a little endian host, you will get the correct
MODULE_ALIAS:

$ grep MODULE_ALIAS drivers/platform/x86/intel/ishtp_eclite.mod.c
MODULE_ALIAS("ishtp:{6A19CC4B-D760-4DE3-B14D-F25EBD0FBCD9}");

However, if you build it on a big endian host, you will get a wrong
MODULE_ALIAS:

$ grep MODULE_ALIAS drivers/platform/x86/intel/ishtp_eclite.mod.c
MODULE_ALIAS("ishtp:{BD0FBCD9-F25E-B14D-4DE3-D7606A19CC4B}");

This issue has been unnoticed because the x86 kernel is most likely built
natively on an x86 host.

The guid field must not be reversed because guid_t is an array of __u8.

Fixes: fa443bc3c1e4 ("HID: intel-ish-hid: add support for MODULE_DEVICE_TABLE()")
Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
---

scripts/mod/file2alias.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c
index 70bf6a2f585c..6583b36dbe69 100644
--- a/scripts/mod/file2alias.c
+++ b/scripts/mod/file2alias.c
@@ -1401,10 +1401,10 @@ static int do_mhi_ep_entry(const char *filename, void *symval, char *alias)
/* Looks like: ishtp:{guid} */
static int do_ishtp_entry(const char *filename, void *symval, char *alias)
{
- DEF_FIELD(symval, ishtp_device_id, guid);
+ DEF_FIELD_ADDR(symval, ishtp_device_id, guid);

strcpy(alias, ISHTP_MODULE_PREFIX "{");
- add_guid(alias, guid);
+ add_guid(alias, *guid);
strcat(alias, "}");

return 1;
--
2.39.2