[binutils-gdb] libctf: fix use-after-free in function dumping

[binutils-gdb] libctf: fix use-after-free in function dumping

[Jose E.Marchesi]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=941accce38bc70a23c62e3c9439b67bf23298124

commit 941accce38bc70a23c62e3c9439b67bf23298124
Author: Nick Alcock <nick.alcock@oracle.com>
Date:   Mon Jun 3 20:26:02 2019 +0100

    libctf: fix use-after-free in function dumping
    
    This is actually a free-before-initializing (i.e. a free of garbage).
    
    libctf/
    	* ctf-dump.c (ctf_dump_funcs): Free in the right place.

Diff:
---
 libctf/ChangeLog  | 4 ++++
 libctf/ctf-dump.c | 2 +-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/libctf/ChangeLog b/libctf/ChangeLog
index d059d58..01b8d8da 100644
--- a/libctf/ChangeLog
+++ b/libctf/ChangeLog
@@ -1,3 +1,7 @@
+2019-06-03  Nick Alcock  <nick.alcock@oracle.com>
+
+	* ctf-dump.c (ctf_dump_funcs): Free in the right place.
+
 2019-05-29  Nick Alcock  <nick.alcock@oracle.com>
 
 	* Makefile.am (ZLIB): New.
diff --git a/libctf/ctf-dump.c b/libctf/ctf-dump.c
index c2ed791..82f63c2 100644
--- a/libctf/ctf-dump.c
+++ b/libctf/ctf-dump.c
@@ -273,7 +273,6 @@ ctf_dump_funcs (ctf_file_t *fp, ctf_dump_state_t *state)
 	goto err;
 
       str = ctf_str_append (str, " ");
-      free (bit);
 
       /* Function name.  */
 
@@ -290,6 +289,7 @@ ctf_dump_funcs (ctf_file_t *fp, ctf_dump_state_t *state)
 	}
       str = ctf_str_append (str, bit);
       str = ctf_str_append (str, " (");
+      free (bit);
 
       /* Function arguments.  */