Aren/NetBSD
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Avoids signedness bit shift in db_get_value()

Browse Source 
Appease UBSan.
This commit is contained in:
kamil 2019-08-23 14:48:50 +00:00
parent 3fb8db10a2
commit 47022302a1
1 changed files with 7 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
sys/ddb/db_access.c
View File

@ -1,4 +1,4 @@
/* $NetBSD: db_access.c,v 1.23 2018/02/04 09:17:54 mrg Exp $ */
/* $NetBSD: db_access.c,v 1.24 2019/08/23 14:48:50 kamil Exp $ */
/*
* Mach Operating System
@ -30,7 +30,7 @@
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: db_access.c,v 1.23 2018/02/04 09:17:54 mrg Exp $");
__KERNEL_RCSID(0, "$NetBSD: db_access.c,v 1.24 2019/08/23 14:48:50 kamil Exp $");
#if defined(_KERNEL_OPT)
#include "opt_kgdb.h"
@ -59,18 +59,21 @@ db_expr_t
db_get_value(db_addr_t addr, size_t size, bool is_signed)
{
char data[sizeof(db_expr_t)] __aligned(sizeof(db_expr_t));
uintmax_t uvalue;
db_expr_t value;
size_t i;
db_read_bytes(addr, size, data);
value = 0;
uvalue = 0;
#if BYTE_ORDER == LITTLE_ENDIAN
for (i = size; i-- > 0;)
#else /* BYTE_ORDER == BIG_ENDIAN */
for (i = 0; i < size; i++)
#endif /* BYTE_ORDER */
value = (value << 8) + (data[i] & 0xFF);
uvalue = (uvalue << 8) + (data[i] & 0xFF);
value = (db_expr_t)uvalue;
if (size < sizeof(db_expr_t) && is_signed
&& (value & ((db_expr_t)1 << (8*size - 1)))) {