On Wed, 2022-07-13 at 11:53 -0700, Kees Cook wrote: > On Wed, Jul 13, 2022 at 11:37:34PM +0800, Ning Qiang wrote: > > In do_adb_query function of drivers/macintosh/adb.c, req->data is > > copy > > form userland. the parameter "req->data[2]" is Missing check, the > > array size of adb_handler[] is 16, so "adb_handler[ > > req->data[2]].original_address" and "adb_handler[ > > req->data[2]].handler_id" will lead to oob read. > > > > Signed-off-by: Ning Qiang <sohu0...@126.com> > > Thanks for catching this! > > Do you have a reproducer for this? I'd expect CONFIG_UBSAN_BOUNDS=y > to notice this at runtime, at least.
For that you would need an ancient Mac with an ADB bus which might be tricky ... I have some in the basement that could possibly be revived if you really insist but I'd rather not waste the time... Cheers, Ben. > > > --- > > drivers/macintosh/adb.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/macintosh/adb.c b/drivers/macintosh/adb.c > > index 439fab4eaa85..1bbb9ca08d40 100644 > > --- a/drivers/macintosh/adb.c > > +++ b/drivers/macintosh/adb.c > > @@ -647,7 +647,7 @@ do_adb_query(struct adb_request *req) > > > > switch(req->data[1]) { > > case ADB_QUERY_GETDEVINFO: > > - if (req->nbytes < 3) > > + if (req->nbytes < 3 || req->data[2] >= 16) > > I'd prefer this was: > > + if (req->nbytes < 3 || req->data[2] >= > ARRAY_SIZE(adb_handler)) > > so it's tied to the actual variable (if its size ever changes). > > With that: > > Reviewed-by: Kees Cook <keesc...@chromium.org> > > -Kees > > > break; > > mutex_lock(&adb_handler_mutex); > > req->reply[0] = adb_handler[req- > > >data[2]].original_address; > > -- > > 2.25.1 > >