From e2944af43eeb95ec612a48cc930a71f9e6a2f219 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Sat, 1 Aug 2009 06:53:03 +0200 Subject: libbb: prevent resursion on malloc failure Signed-off-by: Denys Vlasenko --- libbb/verror_msg.c | 41 +++++++++++++++++++++++++---------------- 1 file changed, 25 insertions(+), 16 deletions(-) diff --git a/libbb/verror_msg.c b/libbb/verror_msg.c index 58846d5..506b906 100644 --- a/libbb/verror_msg.c +++ b/libbb/verror_msg.c @@ -15,7 +15,7 @@ const char *msg_eol = "\n"; void FAST_FUNC bb_verror_msg(const char *s, va_list p, const char* strerr) { - char *msg; + char *msg, *msg1; int applet_len, strerr_len, msgeol_len, used; if (!logmode) @@ -36,27 +36,36 @@ void FAST_FUNC bb_verror_msg(const char *s, va_list p, const char* strerr) applet_len = strlen(applet_name) + 2; /* "applet: " */ strerr_len = strerr ? strlen(strerr) : 0; msgeol_len = strlen(msg_eol); + /* can't use xrealloc: it calls error_msg on failure, + * that may result in a recursion */ /* +3 is for ": " before strerr and for terminating NUL */ - msg = xrealloc(msg, applet_len + used + strerr_len + msgeol_len + 3); - /* TODO: maybe use writev instead of memmoving? Need full_writev? */ - memmove(msg + applet_len, msg, used); - used += applet_len; - strcpy(msg, applet_name); - msg[applet_len - 2] = ':'; - msg[applet_len - 1] = ' '; - if (strerr) { - if (s[0]) { /* not perror_nomsg? */ - msg[used++] = ':'; - msg[used++] = ' '; + msg1 = realloc(msg, applet_len + used + strerr_len + msgeol_len + 3); + if (!msg1) { + msg[used++] = '\n'; /* overwrites NUL */ + applet_len = 0; + } else { + msg = msg1; + /* TODO: maybe use writev instead of memmoving? Need full_writev? */ + memmove(msg + applet_len, msg, used); + used += applet_len; + strcpy(msg, applet_name); + msg[applet_len - 2] = ':'; + msg[applet_len - 1] = ' '; + if (strerr) { + if (s[0]) { /* not perror_nomsg? */ + msg[used++] = ':'; + msg[used++] = ' '; + } + strcpy(&msg[used], strerr); + used += strerr_len; } - strcpy(&msg[used], strerr); - used += strerr_len; + strcpy(&msg[used], msg_eol); + used += msgeol_len; } - strcpy(&msg[used], msg_eol); if (logmode & LOGMODE_STDIO) { fflush(stdout); - full_write(STDERR_FILENO, msg, used + msgeol_len); + full_write(STDERR_FILENO, msg, used); } if (logmode & LOGMODE_SYSLOG) { syslog(LOG_ERR, "%s", msg + applet_len); -- cgit v1.1