linux/net/9p
piaojun c290fba8c4 net/9p/client.c: put refcount of trans_mod in error case in parse_opts()
In my testing, the second mount will fail after umounting successfully.
The reason is that we put refcount of trans_mod in the correct case
rather than the error case in parse_opts() at last.  That will cause the
refcount decrease to -1, and when we try to get trans_mod again in
try_module_get(), we could only increase refcount to 0 which will cause
failure as follows:

parse_opts
  v9fs_get_trans_by_name
    try_module_get : return NULL to caller which cause error

So we should put refcount of trans_mod in error case.

Link: http://lkml.kernel.org/r/5B3F39A0.2030509@huawei.com
Fixes: 9421c3e641 ("net/9p/client.c: fix potential refcnt problem of trans module")
Signed-off-by: Jun Piao <piaojun@huawei.com>
Reviewed-by: Yiwen Jiang <jiangyiwen@huawei.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Dominique Martinet <dominique.martinet@cea.fr>
Tested-by: Dominique Martinet <dominique.martinet@cea.fr>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Ron Minnich <rminnich@sandia.gov>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-07-14 11:11:09 -07:00
..
client.c net/9p/client.c: put refcount of trans_mod in error case in parse_opts() 2018-07-14 11:11:09 -07:00
error.c hlist: drop the node parameter from iterators 2013-02-27 19:10:24 -08:00
Kconfig IB: Revert "remove redundant INFINIBAND kconfig dependencies" 2018-05-28 10:40:16 -06:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mod.c net/9p: correct the variable name in v9fs_get_trans_by_name() comment 2018-05-07 23:38:15 -04:00
protocol.c treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
protocol.h net/9p: Convert net/9p protocol dumps to tracepoints 2011-10-24 11:13:12 -05:00
trans_common.c net/9p: correct some comment errors in 9p file system code 2018-05-10 08:21:53 -04:00
trans_common.h net/9p: remove (now-)unused helpers 2015-04-11 22:28:29 -04:00
trans_fd.c Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
trans_rdma.c net/9p: correct some comment errors in 9p file system code 2018-05-10 08:21:53 -04:00
trans_virtio.c treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
trans_xen.c net/9p/trans_xen.c: don't inclide rwlock.h directly 2018-06-07 17:34:34 -07:00
util.c net/9p: convert to idr_alloc() 2013-02-27 19:10:20 -08:00