Commit d63fb193 authored Mar 27, 2017 by Li Qiang Committed by Greg Kurz Mar 27, 2017

9pfs: fix file descriptor leak



The v9fs_create() and v9fs_lcreate() functions are used to create a file
on the backend and to associate it to a fid. The fid shouldn't be already
in-use, otherwise both functions may silently leak a file descriptor or
allocated memory. The current code doesn't check that.

This patch ensures that the fid isn't already associated to anything
before using it.

Signed-off-by: Li Qiang <liqiang6-s@360.cn>
(reworded the changelog, Greg Kurz)
Signed-off-by: Greg Kurz <groug@kaod.org>

parent eb06c9e2

hw/9pfs/9p.c

+8 −0

Original line number	Diff line number	Diff line
		@@ -1550,6 +1550,10 @@ static void coroutine_fn v9fs_lcreate(void *opaque)
		err = -ENOENT;
		goto out_nofid;
		}
		if (fidp->fid_type != P9_FID_NONE) {
		err = -EINVAL;
		goto out;
		}

		flags = get_dotl_openflags(pdu->s, flags);
		err = v9fs_co_open2(pdu, fidp, &name, gid,
		@@ -2153,6 +2157,10 @@ static void coroutine_fn v9fs_create(void *opaque)
		err = -EINVAL;
		goto out_nofid;
		}
		if (fidp->fid_type != P9_FID_NONE) {
		err = -EINVAL;
		goto out;
		}
		if (perm & P9_STAT_MODE_DIR) {
		err = v9fs_co_mkdir(pdu, fidp, &name, perm & 0777,
		fidp->uid, -1, &stbuf);