[PATCH 6.0 0148/1073] ocfs2: fix memory leak in ocfs2_mount_volume()

Greg Kroah-Hartman
2022-12-28T15:13:07Z

From: Li Zetao <ocfs2-devel@oss.oracle.com>

[ Upstream commit ce2fcf1516d674a174d9b34d1e1024d64de9fba3 ]

There is a memory leak reported by kmemleak:

unreferenced object 0xffff88810cc65e60 (size 32):
comm "mount.ocfs2", pid 23753, jiffies 4302528942 (age 34735.105s)
hex dump (first 32 bytes):
10 00 00 00 00 00 00 00 00 01 01 01 01 01 01 01 ................
01 01 01 01 01 01 01 01 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff8170f73d>] __kmalloc+0x4d/0x150
[<ffffffffa0ac3f51>] ocfs2_compute_replay_slots+0x121/0x330 [ocfs2]
[<ffffffffa0b65165>] ocfs2_check_volume+0x485/0x900 [ocfs2]
[<ffffffffa0b68129>] ocfs2_mount_volume.isra.0+0x1e9/0x650 [ocfs2]
[<ffffffffa0b7160b>] ocfs2_fill_super+0xe0b/0x1740 [ocfs2]
[<ffffffff818e1fe2>] mount_bdev+0x312/0x400
[<ffffffff819a086d>] legacy_get_tree+0xed/0x1d0
[<ffffffff818de82d>] vfs_get_tree+0x7d/0x230
[<ffffffff81957f92>] path_mount+0xd62/0x1760
[<ffffffff81958a5a>] do_mount+0xca/0xe0
[<ffffffff81958d3c>] __x64_sys_mount+0x12c/0x1a0
[<ffffffff82f26f15>] do_syscall_64+0x35/0x80
[<ffffffff8300006a>] entry_SYSCALL_64_after_hwframe+0x46/0xb0

This call stack is related to two problems. Firstly, the ocfs2 super uses
"replay_map" to trace online/offline slots, in order to recover offline
slots during recovery and mount. But when ocfs2_truncate_log_init()
returns an error in ocfs2_mount_volume(), the memory of "replay_map" will
not be freed in error handling path. Secondly, the memory of "replay_map"
will not be freed if d_make_root() returns an error in ocfs2_fill_super().
But the memory of "replay_map" will be freed normally when completing
recovery and mount in ocfs2_complete_mount_recovery().

Fix the first problem by adding error handling path to free "replay_map"
when ocfs2_truncate_log_init() fails. And fix the second problem by
calling ocfs2_free_replay_slots(osb) in the error handling path
"out_dismount". In addition, since ocfs2_free_replay_slots() is static,
it is necessary to remove its static attribute and declare it in header
file.

Link: https://lkml.kernel.org/r/20221109074627.2303950-1-lizetao1@huawei.com
Fixes: 9140db04ef18 ("ocfs2: recover orphans in offline slots during recovery and mount")
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Gang He <ghe@suse.com>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/ocfs2/journal.c | 2 +-
fs/ocfs2/journal.h | 1 +
fs/ocfs2/super.c | 5 ++++-
3 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/fs/ocfs2/journal.c b/fs/ocfs2/journal.c
index fa87d89cf754..1be7d440eff3 100644
--- a/fs/ocfs2/journal.c
+++ b/fs/ocfs2/journal.c
@@ -157,7 +157,7 @@ static void ocfs2_queue_replay_slots(struct ocfs2_super *osb,
replay_map->rm_state = REPLAY_DONE;
}

-static void ocfs2_free_replay_slots(struct ocfs2_super *osb)
+void ocfs2_free_replay_slots(struct ocfs2_super *osb)
{
struct ocfs2_replay_map *replay_map = osb->replay_map;

diff --git a/fs/ocfs2/journal.h b/fs/ocfs2/journal.h
index 969d0aa28718..41c382f68529 100644
--- a/fs/ocfs2/journal.h
+++ b/fs/ocfs2/journal.h
@@ -150,6 +150,7 @@ int ocfs2_recovery_init(struct ocfs2_super *osb);
void ocfs2_recovery_exit(struct ocfs2_super *osb);

int ocfs2_compute_replay_slots(struct ocfs2_super *osb);
+void ocfs2_free_replay_slots(struct ocfs2_super *osb);
/*
* Journal Control:
* Initialize, Load, Shutdown, Wipe a journal.
diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index e2cc9eec287c..78441e466e6f 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -1159,6 +1159,7 @@ static int ocfs2_fill_super(struct super_block *sb, void *data, int silent)
out_dismount:
atomic_set(&osb->vol_state, VOLUME_DISABLED);
wake_up(&osb->osb_mount_event);
+ ocfs2_free_replay_slots(osb);
ocfs2_dismount_volume(sb, 1);
goto out;

@@ -1824,12 +1825,14 @@ static int ocfs2_mount_volume(struct super_block *sb)
status = ocfs2_truncate_log_init(osb);
if (status < 0) {
mlog_errno(status);
- goto out_system_inodes;
+ goto out_check_volume;
}

ocfs2_super_unlock(osb, 1);
return 0;

+out_check_volume:
+ ocfs2_free_replay_slots(osb);
out_system_inodes:
if (osb->local_alloc_state == OCFS2_LA_ENABLED)
ocfs2_shutdown_local_alloc(osb);
--
2.35.1