[Cluster-devel] [PATCH dlm/next 3/7] fs: dlm: fix dlm_local_addr memory leak

[Alexander Aring <aahringo@redhat.com>]

This patch fixes the following memory detected by kmemleak and umount
gfs2 filesystem which removed the last lockspace:

unreferenced object 0xffff9264f4f48f00 (size 128):
  comm "mount", pid 425, jiffies 4294690253 (age 48.159s)
  hex dump (first 32 bytes):
    02 00 52 48 c0 a8 7a fb 00 00 00 00 00 00 00 00  ..RH..z.........
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<0000000067a34940>] kmemdup+0x18/0x40
    [<00000000c935f9ab>] init_local+0x4c/0xa0
    [<00000000bbd286ef>] dlm_lowcomms_start+0x28/0x160
    [<00000000a86625cb>] dlm_new_lockspace+0x7e/0xb80
    [<000000008df6cd63>] gdlm_mount+0x1cc/0x5de
    [<00000000b67df8c7>] gfs2_lm_mount.constprop.0+0x1a3/0x1d3
    [<000000006642ac5e>] gfs2_fill_super+0x717/0xba9
    [<00000000d3ab7118>] get_tree_bdev+0x17f/0x280
    [<000000001975926e>] gfs2_get_tree+0x21/0x90
    [<00000000561ce1c4>] vfs_get_tree+0x28/0xc0
    [<000000007fecaf63>] path_mount+0x434/0xc00
    [<00000000636b9594>] __x64_sys_mount+0xe3/0x120
    [<00000000cc478a33>] do_syscall_64+0x33/0x40
    [<00000000ce9ccf01>] entry_SYSCALL_64_after_hwframe+0x44/0xa9

Signed-off-by: Alexander Aring <aahringo@redhat.com>
---
 fs/dlm/lowcomms.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/fs/dlm/lowcomms.c b/fs/dlm/lowcomms.c
index 9db7126de793..d0ece252a0d9 100644
--- a/fs/dlm/lowcomms.c
+++ b/fs/dlm/lowcomms.c
@@ -1234,6 +1234,14 @@ static void init_local(void)
 	}
 }
 
+static void deinit_local(void)
+{
+	int i;
+
+	for (i = 0; i < dlm_local_count; i++)
+		kfree(dlm_local_addr[i]);
+}
+
 /* Initialise SCTP socket and bind to all interfaces */
 static int sctp_listen_for_all(void)
 {
@@ -1663,6 +1671,7 @@ void dlm_lowcomms_stop(void)
 	clean_writequeues();
 	foreach_conn(free_conn);
 	work_stop();
+	deinit_local();
 }
 
 int dlm_lowcomms_start(void)
-- 
2.26.2