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. > --- > 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 > -- Kees Cook