[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH] slirp: use less predictable directory name in /
From: |
Markus Armbruster |
Subject: |
Re: [Qemu-devel] [PATCH] slirp: use less predictable directory name in /tmp for smb config (CVE-2015-4037) |
Date: |
Mon, 01 Jun 2015 10:01:55 +0200 |
User-agent: |
Gnus/5.13 (Gnus v5.13) Emacs/24.3 (gnu/linux) |
Michael Tokarev <address@hidden> writes:
> In this version I used mkdtemp(3) which is:
>
> _BSD_SOURCE
> || /* Since glibc 2.10: */
> (_POSIX_C_SOURCE >= 200809L || _XOPEN_SOURCE >= 700)
>
> so should be available on systems we care about.
>
> Signed-off-by: Michael Tokarev <address@hidden>
> ---
> net/slirp.c | 6 ++----
> 1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/net/slirp.c b/net/slirp.c
> index 9bbed74..0ad32ad 100644
> --- a/net/slirp.c
> +++ b/net/slirp.c
> @@ -481,7 +481,6 @@ static void slirp_smb_cleanup(SlirpState *s)
> static int slirp_smb(SlirpState* s, const char *exported_dir,
> struct in_addr vserver_addr)
> {
> - static int instance;
> char smb_conf[128];
> char smb_cmdline[128];
> struct passwd *passwd;
> @@ -505,9 +504,8 @@ static int slirp_smb(SlirpState* s, const char
> *exported_dir,
> return -1;
> }
>
> - snprintf(s->smb_dir, sizeof(s->smb_dir), "/tmp/qemu-smb.%ld-%d",
> - (long)getpid(), instance++);
> - if (mkdir(s->smb_dir, 0700) < 0) {
> + strcpy(s->smb_dir, "/tmp/qemu-smb.XXXXXX");
> + if (!mkdtemp(s->smb_dir)) {
> error_report("could not create samba server dir '%s'", s->smb_dir);
> return -1;
> }
Uh, I have to suspend my R-by. This clobbers s->smb_dir[] when
mkdtemp() fails. Is that safe? Explain why, and get my R-by back.
The alternative "[PATCH] net: fix insecure temporary file creation in
SLiRP" doesn't clobber it.
http://lists.nongnu.org/archive/html/qemu-devel/2015-06/msg00005.html
- Re: [Qemu-devel] [PATCH] slirp: use less predictable directory name in /tmp for smb config (CVE-2015-4037),
Markus Armbruster <=