diff options
author | Pan Xinhui <xinhuix.pan@intel.com> | 2015-03-28 10:42:56 +0800 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-06-06 08:19:35 -0700 |
commit | ad34c79b5fda56d036ce3274f286a454887d76cc (patch) | |
tree | 82fa790f470266a2e0a7c4b7a5709cb8eca8dedf /fs/ext4 | |
parent | 68275f52fca669da9aba3692c08048faa36059f9 (diff) |
tty/n_gsm.c: fix a memory leak when gsmtty is removed
commit 8f9cfeed3eae86c70d3b04445a6f2036b27b6304 upstream.
when gsmtty_remove put dlci, it will cause memory leak if dlci->port's refcount is zero.
So we do the cleanup work in .cleanup callback instead.
dlci will be last put in two call chains.
1) gsmld_close -> gsm_cleanup_mux -> gsm_dlci_release -> dlci_put
2) gsmld_remove -> dlci_put
so there is a race. the memory leak depends on the race.
In call chain 2. we hit the memory leak. below comment tells.
release_tty -> tty_driver_remove_tty -> gsmtty_remove -> dlci_put -> tty_port_destructor (WARN_ON(port->itty) and return directly)
|
tty->port->itty = NULL;
|
tty_kref_put ---> release_one_tty -> gsmtty_cleanup (added by our patch)
So our patch fix the memory leak by doing the cleanup work after tty core did.
Signed-off-by: Pan Xinhui <xinhuix.pan@intel.com>
Fixes: dfabf7ffa30585
Acked-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/ext4')
0 files changed, 0 insertions, 0 deletions