From 3c6c0527e691b4906e8ad2527fb2bfd2a8782cc1 Mon Sep 17 00:00:00 2001 From: jilles Date: Wed, 24 Jun 2015 20:51:48 +0000 Subject: sh: Fix some arithmetic undefined behaviour. Fix shifts of possibly negative numbers found with ubsan and avoid signed integer overflow when hashing an extremely long command name. MFC after: 1 week --- bin/sh/alias.c | 2 +- bin/sh/exec.c | 5 ++--- 2 files changed, 3 insertions(+), 4 deletions(-) (limited to 'bin') diff --git a/bin/sh/alias.c b/bin/sh/alias.c index 21f3f44..a77ce99 100644 --- a/bin/sh/alias.c +++ b/bin/sh/alias.c @@ -248,7 +248,7 @@ hashalias(const char *p) { unsigned int hashval; - hashval = *p << 4; + hashval = (unsigned char)*p << 4; while (*p) hashval+= *p++; return &atab[hashval % ATABSIZE]; diff --git a/bin/sh/exec.c b/bin/sh/exec.c index c9d4126..7d18c3c 100644 --- a/bin/sh/exec.c +++ b/bin/sh/exec.c @@ -522,17 +522,16 @@ static struct tblentry **lastcmdentry; static struct tblentry * cmdlookup(const char *name, int add) { - int hashval; + unsigned int hashval; const char *p; struct tblentry *cmdp; struct tblentry **pp; size_t len; p = name; - hashval = *p << 4; + hashval = (unsigned char)*p << 4; while (*p) hashval += *p++; - hashval &= 0x7FFF; pp = &cmdtable[hashval % CMDTABLESIZE]; for (cmdp = *pp ; cmdp ; cmdp = cmdp->next) { if (equal(cmdp->cmdname, name)) -- cgit v1.1