f5c9edcc8f
Resolves: RHEL-28047 Signed-off-by: Paulo Alcantara <paalcant@redhat.com>
47 lines
1.4 KiB
Diff
47 lines
1.4 KiB
Diff
From 73146385da0945c78af0fbdc08d2bf260db709d5 Mon Sep 17 00:00:00 2001
|
|
From: Paulo Alcantara <pc@manguebit.com>
|
|
Date: Fri, 8 Mar 2024 12:06:15 -0300
|
|
Subject: [PATCH] cifs.upcall: fix UAF in get_cachename_from_process_env()
|
|
|
|
Whether lseek(2) fails or @bufsize * 2 > ENV_BUF_MAX, then @buf would
|
|
end up being freed twice. For instance:
|
|
|
|
cifs-utils-7.0/cifs.upcall.c:501: freed_arg: "free" frees "buf".
|
|
cifs-utils-7.0/cifs.upcall.c:524: double_free: Calling "free" frees
|
|
pointer "buf" which has already been freed.
|
|
522| }
|
|
523| out_close:
|
|
524|-> free(buf);
|
|
525| close(fd);
|
|
526| return cachename;
|
|
|
|
Fix this by setting @buf to NULL after freeing it to prevent UAF.
|
|
|
|
Fixes: ed97e4ecab4e ("cifs.upcall: allow scraping of KRB5CCNAME out of initiating task's /proc/<pid>/environ file")
|
|
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
|
|
---
|
|
cifs.upcall.c | 5 +++--
|
|
1 file changed, 3 insertions(+), 2 deletions(-)
|
|
|
|
diff --git a/cifs.upcall.c b/cifs.upcall.c
|
|
index 52c03280dbe0..ff6f2bd271bc 100644
|
|
--- a/cifs.upcall.c
|
|
+++ b/cifs.upcall.c
|
|
@@ -498,10 +498,11 @@ retry:
|
|
/* We read to the end of the buffer. Double and try again */
|
|
syslog(LOG_DEBUG, "%s: read to end of buffer (%zu bytes)\n",
|
|
__func__, bufsize);
|
|
- free(buf);
|
|
- bufsize *= 2;
|
|
if (lseek(fd, 0, SEEK_SET) < 0)
|
|
goto out_close;
|
|
+ free(buf);
|
|
+ buf = NULL;
|
|
+ bufsize *= 2;
|
|
goto retry;
|
|
}
|
|
|
|
--
|
|
2.44.0
|
|
|