From 2f661dc20617ba6fdeb2d7e243dc898653faafea Mon Sep 17 00:00:00 2001 From: Lubomir Rintel Date: Tue, 26 Apr 2011 21:50:26 +0200 Subject: [PATCH] Always copy the string before expanding it It might get freed during expansion, e.g. with eval function. A simple reproducer: TRUE = $(eval TRUE := true) all: $(TRUE) --- ChangeLog | 5 +++++ expand.c | 18 +++++++++--------- 2 files changed, 14 insertions(+), 9 deletions(-) diff --git a/ChangeLog b/ChangeLog index 91878fb..7519164 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,8 @@ +2011-04-26 Lubomir Rintel + + * expand.c (variable_expand_string): Always copy the string + to expand. + 2010-08-13 Paul Smith * NEWS: Accidentally forgot to back out the sorted wildcard diff --git a/expand.c b/expand.c index 2315b06..3e6e346 100644 --- a/expand.c +++ b/expand.c @@ -197,7 +197,7 @@ variable_expand_string (char *line, const char *string, long length) { struct variable *v; const char *p, *p1; - char *abuf = NULL; + char *abuf; char *o; unsigned int line_offset; @@ -214,14 +214,15 @@ variable_expand_string (char *line, const char *string, long length) /* If we want a subset of the string, allocate a temporary buffer for it. Most of the functions we use here don't work with length limits. */ - if (length > 0 && string[length] != '\0') + if (length == -1) { - abuf = xmalloc(length+1); - memcpy(abuf, string, length); - abuf[length] = '\0'; - string = abuf; + length = strlen (string); } - p = string; + + abuf = xmalloc(length+1); + memcpy(abuf, string, length); + abuf[length] = '\0'; + p = abuf; while (1) { @@ -411,8 +412,7 @@ variable_expand_string (char *line, const char *string, long length) ++p; } - if (abuf) - free (abuf); + free (abuf); variable_buffer_output (o, "", 1); return (variable_buffer + line_offset); -- 1.7.4.1