When passed the empty string, tprint() will allocate a zero-length
buffer and then branch on its first element (``if (*buffer) { … }``)
which has never been initialized.
Prevent the invalid access by checking for the empty string and skipping
the printing routine entirely if appropriate.
Signed-off-by: Philipp Gesang
---
source/texk/web2c/luatexdir/tex/printing.w | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/source/texk/web2c/luatexdir/tex/printing.w b/source/texk/web2c/luatexdir/tex/printing.w
index 478d55f..675fa45 100644
--- a/source/texk/web2c/luatexdir/tex/printing.w
+++ b/source/texk/web2c/luatexdir/tex/printing.w
@@ -367,6 +367,10 @@ void tprint(const char *sss)
int newlinechar = int_par(new_line_char_code);
int dolog = 0;
int doterm = 0;
+ const size_t sss_len = strlen(sss);
+ if (sss_len == 0u) { /* nothing to print */
+ return;
+ }
switch (selector) {
case no_print:
return;
@@ -413,7 +417,7 @@ void tprint(const char *sss)
}
/* what is left is the 3 term/log settings */
if (dolog || doterm) {
- buffer = xmalloc(strlen(sss)*3);
+ buffer = xmalloc(sss_len*3);
if (dolog) {
const unsigned char *ss = (const unsigned char *) sss;
while (*ss) {
--
2.8.0
