strace/SOURCES/0031-evdev-fix-array-size-calculation-in-decode_bitset_.patch
2021-09-10 04:55:58 +00:00

58 lines
1.7 KiB
Diff

From 96194ed74158f0b9976fae43a910ad14eaea141e Mon Sep 17 00:00:00 2001
From: Eugene Syromyatnikov <evgsyr@gmail.com>
Date: Fri, 12 Jul 2019 14:57:28 +0200
Subject: [PATCH 2/3] evdev: fix array size calculation in decode_bitset_
max_nr is in bits (as it is a number of flags), result is in bytes, and
the array allocation has to be in personality words.
There's still an open question, however, what to do on big-endian
architectures when a non-divisible-by-4 value is returned.
* evdev.c (decode_bitset_): Declare size_bits, initialise it and use it
later instead of size; round up size by personality's word boundary.
---
evdev.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/evdev.c b/evdev.c
index 4b811cf8..a3d9cb55 100644
--- a/evdev.c
+++ b/evdev.c
@@ -151,10 +151,14 @@ decode_bitset_(struct tcb *const tcp, const kernel_ulong_t arg,
tprints(", ");
unsigned int size;
+ unsigned int size_bits;
+
if ((kernel_ulong_t) tcp->u_rval > max_nr / 8)
- size = max_nr;
+ size_bits = max_nr;
else
- size = tcp->u_rval * 8;
+ size_bits = tcp->u_rval * 8;
+
+ size = ROUNDUP(ROUNDUP_DIV(size_bits, 8), current_wordsize);
if (syserror(tcp) || !size) {
printaddr(arg);
@@ -170,13 +174,13 @@ decode_bitset_(struct tcb *const tcp, const kernel_ulong_t arg,
tprints("[");
int bit_displayed = 0;
- int i = next_set_bit(decoded_arg, 0, size);
+ int i = next_set_bit(decoded_arg, 0, size_bits);
if (i < 0) {
tprints(" 0 ");
} else {
printxval_dispatch(decode_nr, decode_nr_size, i, dflt, xt);
- while ((i = next_set_bit(decoded_arg, i + 1, size)) > 0) {
+ while ((i = next_set_bit(decoded_arg, i + 1, size_bits)) > 0) {
if (abbrev(tcp) && bit_displayed >= 3) {
tprints(", ...");
break;
--
2.13.6