[PATCH] sepdebugcrcfix: Don't crash if .gnu_debuglink doesn't contain a file string.

[Mark Wielaard]

If the .gnu_debuglink section didn't contain a valid file string then we would crash.
Produce an error instead.

	* tools/sepdebugcrcfix.c (process): Produce an error when zerop is NULL.

Signed-off-by: Mark Wielaard <mark@klomp.org>
---
 tools/sepdebugcrcfix.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/tools/sepdebugcrcfix.c b/tools/sepdebugcrcfix.c
index 20800ba..024d09c 100644
--- a/tools/sepdebugcrcfix.c
+++ b/tools/sepdebugcrcfix.c
@@ -258,10 +258,13 @@ process (Elf *elf, int fd, const char *fname)
 	  continue;
 	}
       const uint8_t *zerop = memchr (data->d_buf, '\0', data->d_size);
-      const uint8_t *crcp = (zerop == NULL
-			     ? NULL
-			     : (const uint8_t *) ((uintptr_t) (zerop + 1 + 3)
-						  & -4));
+      if (zerop == NULL)
+	{
+	  error (0, 0, _("no file string in section \"%s\" # %zu in \"%s\""),
+		 scnname, elf_ndxscn (scn), fname);
+	  continue;
+	}
+      const uint8_t *crcp = (const uint8_t *) ((uintptr_t) (zerop + 1 + 3) & -4);
       if (crcp + 4 != (uint8_t *) data->d_buf + data->d_size)
 	{
 	  error (0, 0, _("invalid format of section \"%s\" # %zu in \"%s\""),
-- 
2.32.0