On Wed, Aug 26, 2020 at 6:36 PM Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > On Wed, Aug 26, 2020 at 05:02:38PM +0200, Marek Szyprowski wrote: > > On 26.08.2020 15:43, Greg KH wrote: > > > Brooke Basile (2): > > > USB: gadget: u_f: add overflow checks to VLA macros > > > > Sorry, but the above patch breaks USB Ethernet Gadget operation. It also > > didn't get the proper testing in linux-next (next-20200826 is the first > > one with this patch). > > > > This is how it explodes on Samsung Exynos (ARM 32bit) based board with > > g_ether module loaded: > Odd, for a "normal" descriptor, the logic should have remained the same > as without this patch. > Brooke, any ideas? I have an idea. Does below fix this? -- With Best Regards, Andy Shevchenko
diff --git a/drivers/usb/gadget/u_f.h b/drivers/usb/gadget/u_f.h index df4e1dcb357d..0b5c5f0dd073 100644 --- a/drivers/usb/gadget/u_f.h +++ b/drivers/usb/gadget/u_f.h @@ -25,8 +25,8 @@ size_t offset = 0; \ if (groupname##__next != SIZE_MAX) { \ size_t align_mask = __alignof__(type) - 1; \ - size_t offset = (groupname##__next + align_mask) \ - & ~align_mask; \ + offset = (groupname##__next + align_mask) & \ + ~align_mask; \ size_t size = array_size(n, sizeof(type)); \ if (check_add_overflow(offset, size, \ &groupname##__next)) { \ @@ -43,8 +43,8 @@ size_t offset = 0; \ if (groupname##__next != SIZE_MAX) { \ size_t align_mask = __alignof__(type) - 1; \ - size_t offset = (groupname##__next + align_mask) \ - & ~align_mask; \ + offset = (groupname##__next + align_mask) & \ + ~align_mask; \ if (check_add_overflow(offset, groupname##_##name##__sz,\ &groupname##__next)) { \ groupname##__next = SIZE_MAX; \