From 7ada13f3a40e2f58aea335cf910666378e7dd99a Mon Sep 17 00:00:00 2001 From: Eugene Syromyatnikov Date: Fri, 12 Jul 2019 14:38:33 +0200 Subject: [PATCH] evdev: avoid bit vector decoding on non-successful and 0 return codes Reported by Clang. strace/evdev.c:157:3: note: The value 0 is assigned to 'size' # size = tcp->u_rval * 8; # ^~~~~~~~~~~~~~~~~~~~~~ strace/evdev.c:158:2: warning: Declared variable-length array (VLA) has zero size # char decoded_arg[size]; # ^ * evdev.c (decode_bitset_): Bail out before decoded_arg VLA definition. --- evdev.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/evdev.c b/evdev.c index e402d26e..4b811cf8 100644 --- a/evdev.c +++ b/evdev.c @@ -155,6 +155,13 @@ decode_bitset_(struct tcb *const tcp, const kernel_ulong_t arg, size = max_nr; else size = tcp->u_rval * 8; + + if (syserror(tcp) || !size) { + printaddr(arg); + + return RVAL_IOCTL_DECODED; + } + char decoded_arg[size]; if (umove_or_printaddr(tcp, arg, &decoded_arg)) -- 2.40.0