From 0134f725b7d254ddbc3cc6dd72399edea832559c Mon Sep 17 00:00:00 2001 From: Patrick Brown Date: Sun, 6 Dec 2015 15:09:42 +0100 Subject: builtin: Reject malformed printf specifications with digits after '*' Dash doesn't notice when a format string has digits following a * width specifier. $ dash -c 'printf "%*0s " 1 2 && echo FAIL || echo OK' %10s FAIL $ bash -c 'printf "%*0s " 1 2 && echo FAIL || echo OK' bash: line 0: printf: `0': invalid format character OK $ mksh -c 'printf "%*0s " 1 2 && echo FAIL || echo OK' printf: %*0: invalid conversion specification OK With this patch dash complains about the malformed specifications. $ ./src/dash -c 'printf "%*0s " 1 2 && echo FAIL || echo OK' ./src/dash: 1: printf: %*0: invalid directive OK Fixes: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=779618 Originally-by: Patrick Brown Forwarded-by: Gioele Barabucci Signed-off-by: Herbert Xu --- src/bltin/printf.c | 23 +++++++++++++++-------- 1 file changed, 15 insertions(+), 8 deletions(-) (limited to 'src/bltin') diff --git a/src/bltin/printf.c b/src/bltin/printf.c index 9673e10..1112253 100644 --- a/src/bltin/printf.c +++ b/src/bltin/printf.c @@ -175,17 +175,24 @@ pc: /* skip to field width */ fmt += strspn(fmt, SKIP1); - if (*fmt == '*') - *param++ = getuintmax(1); - - /* skip to possible '.', get following precision */ - fmt += strspn(fmt, SKIP2); - if (*fmt == '.') + if (*fmt == '*') { ++fmt; - if (*fmt == '*') *param++ = getuintmax(1); + } else { + /* skip to possible '.', + * get following precision + */ + fmt += strspn(fmt, SKIP2); + } - fmt += strspn(fmt, SKIP2); + if (*fmt == '.') { + ++fmt; + if (*fmt == '*') { + ++fmt; + *param++ = getuintmax(1); + } else + fmt += strspn(fmt, SKIP2); + } ch = *fmt; if (!ch) -- cgit 1.4.1