diff options
| author | Greg Kurz <groug@kaod.org> | 2017-02-26 23:43:25 +0100 |
|---|---|---|
| committer | Michael Roth <mdroth@linux.vnet.ibm.com> | 2017-03-16 12:07:37 -0500 |
| commit | d3c54bf9e7f079e43f37bb0d7c2657e8976d3e1d (patch) | |
| tree | ee8142a27cdd0fcecc1fc6bf5fcb81aa79169a01 | |
| parent | 91225c670a0eec5354d679b4fd676e572cc37a57 (diff) | |
9pfs: local: statfs: don't follow symlinks
The local_statfs() callback is vulnerable to symlink attacks because it
calls statfs() which follows symbolic links in all path elements.
This patch converts local_statfs() to rely on open_nofollow() and fstatfs()
instead.
This partly fixes CVE-2016-9602.
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
(cherry picked from commit 31e51d1c15b35dc98b88a301812914b70a2b55dc)
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
| -rw-r--r-- | hw/9pfs/9p-local.c | 10 |
1 files changed, 4 insertions, 6 deletions
diff --git a/hw/9pfs/9p-local.c b/hw/9pfs/9p-local.c index fa1477f6f1..80b3964a59 100644 --- a/hw/9pfs/9p-local.c +++ b/hw/9pfs/9p-local.c @@ -1078,13 +1078,11 @@ static int local_fsync(FsContext *ctx, int fid_type, static int local_statfs(FsContext *s, V9fsPath *fs_path, struct statfs *stbuf) { - char *buffer; - int ret; - char *path = fs_path->data; + int fd, ret; - buffer = rpath(s, path); - ret = statfs(buffer, stbuf); - g_free(buffer); + fd = local_open_nofollow(s, fs_path->data, O_RDONLY, 0); + ret = fstatfs(fd, stbuf); + close_preserve_errno(fd); return ret; } |