6.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Tudor Ambarus <tudor.ambarus@xxxxxxxxxx>
commit 382b6eabb0316b7334d97afbdcf33a4e20b0ecd8 upstream.
The blamed commit made ffs_func_disable() always return -EINVAL as the
method calls ffs_func_set_alt() with the ``alt`` argument being
``(unsigned)-1``, which is always greater than MAX_ALT_SETTINGS.
Use the MAX_ALT_SETTINGS check just in the f->set_alt() code path,
f->disable() doesn't care about the ``alt`` parameter.
Make a surgical fix, but really the f->disable() code shall be pulled
out from ffs_func_set_alt(), the code will become clearer. A patch will
follow.
Note that ffs_func_disable() always returning -EINVAL made pixel6 crash
on USB disconnect.
Fixes: 2f550553e23c ("usb: gadget: f_fs: Add the missing get_alt callback")
Cc: stable <stable@xxxxxxxxxx>
Reported-by: William McVicker <willmcvicker@xxxxxxxxxx>
Signed-off-by: Tudor Ambarus <tudor.ambarus@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240802140428.2000312-2-tudor.ambarus@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/gadget/function/f_fs.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -3731,10 +3731,10 @@ static int ffs_func_set_alt(struct usb_f
struct ffs_data *ffs = func->ffs;
int ret = 0, intf;
- if (alt > MAX_ALT_SETTINGS)
- return -EINVAL;
-
if (alt != (unsigned)-1) {
+ if (alt > MAX_ALT_SETTINGS)
+ return -EINVAL;
+
intf = ffs_func_revmap_intf(func, interface);
if (intf < 0)
return intf;
