cifs-utils/0012-mount.cifs-Fix-invalid-free.patch
2019-10-09 16:13:33 +00:00

78 lines
2.4 KiB
Diff

From d48a8d61c07e3841ffd71f3aafa5db28dd35b6a7 Mon Sep 17 00:00:00 2001
From: "Paulo Alcantara (SUSE)" <pc@cjr.nz>
Date: Thu, 19 Sep 2019 08:35:47 -0300
Subject: [PATCH] mount.cifs: Fix invalid free
When attemping to chdir into non-existing directories, mount.cifs
crashes.
This patch fixes the following ASAN report:
$ ./mount.cifs //localhost/foo /mnt/invalid-dir -o ...
/mnt/bar -o username=foo,password=foo,vers=1.0
Couldn't chdir to /mnt/bar: No such file or directory
=================================================================
==11846==ERROR: AddressSanitizer: attempting free on address which was
not malloc()-ed: 0x7ffd86332e97 in thread T0
#0 0x7f0860ca01e7 in
__interceptor_free (/usr/lib64/libasan.so.5+0x10a1e7)
#1 0x557edece9ccb in
acquire_mountpoint (/home/paulo/src/cifs-utils/mount.cifs+0xeccb)
#2 0x557edecea63d in
main (/home/paulo/src/cifs-utils/mount.cifs+0xf63d)
#3 0x7f08609f0bca in __libc_start_main (/lib64/libc.so.6+0x26bca)
#4 0x557edece27d9 in
_start (/home/paulo/src/cifs-utils/mount.cifs+0x77d9)
Address 0x7ffd86332e97 is located in stack of thread T0 at offset 8951
in frame
#0 0x557edece9ce0 in
main (/home/paulo/src/cifs-utils/mount.cifs+0xece0)
This frame has 2 object(s):
[48, 52) 'rc' (line 1959)
[64, 72) 'mountpoint' (line 1955) <== Memory access at offset 8951
overflows this variable
HINT: this may be a false positive if your program uses some custom
stack unwind mechanism, swapcontext or vfork
(longjmp and C++ exceptions *are* supported)
SUMMARY: AddressSanitizer: bad-free (/usr/lib64/libasan.so.5+0x10a1e7)
in __interceptor_free
==11846==ABORTING
Fixes: bf7f48f4c7dc ("mount.cifs.c: fix memory leaks in main func")
Signed-off-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
---
mount.cifs.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/mount.cifs.c b/mount.cifs.c
index 7748d54aa814..0c38adcd99b1 100644
--- a/mount.cifs.c
+++ b/mount.cifs.c
@@ -1893,7 +1893,7 @@ acquire_mountpoint(char **mountpointp)
int rc, dacrc;
uid_t realuid, oldfsuid;
gid_t oldfsgid;
- char *mountpoint;
+ char *mountpoint = NULL;
/*
* Acquire the necessary privileges to chdir to the mountpoint. If
@@ -1942,9 +1942,9 @@ restore_privs:
gid_t __attribute__((unused)) gignore = setfsgid(oldfsgid);
}
- if (rc) {
- free(*mountpointp);
- }
+ if (rc)
+ free(mountpoint);
+
return rc;
}
--
2.23.0