From: Jeff Layton Date: Fri, 25 Sep 2009 11:03:44 +0000 (-0400) Subject: mount.cifs: check access of credential files before opening X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3ea466e1b8e69d59736bf5b4452769014b17f0f3;p=thirdparty%2Fsamba.git mount.cifs: check access of credential files before opening It's possible for an unprivileged user to pass a setuid mount.cifs a credential or password file to which he does not have access. This can cause mount.cifs to open the file on his behalf and possibly leak the info in the first few lines of the file. Check the access permissions of the file before opening it. Reported-by: Ronald Volgers Signed-off-by: Jeff Layton Acked-by: Steve French Part 1/2 of a fix for CVE-2009-2948. (cherry picked from commit b656deb5d7e97176c32b61b7659258846db16887) --- diff --git a/source/client/mount.cifs.c b/source/client/mount.cifs.c index d05115b892d..cee9188f9f9 100644 --- a/source/client/mount.cifs.c +++ b/source/client/mount.cifs.c @@ -199,6 +199,11 @@ static int open_cred_file(char * file_name) char * temp_val; FILE * fs; int i, length; + + i = access(file_name, R_OK); + if (i) + return i; + fs = fopen(file_name,"r"); if(fs == NULL) return errno; @@ -321,6 +326,12 @@ static int get_password_from_file(int file_descript, char * filename) } if(filename != NULL) { + rc = access(filename, R_OK); + if (rc) { + fprintf(stderr, "mount.cifs failed: access check of %s failed: %s\n", + filename, strerror(errno)); + exit(EX_SYSERR); + } file_descript = open(filename, O_RDONLY); if(file_descript < 0) { printf("mount.cifs failed. %s attempting to open password file %s\n",