| Message ID | 20221108152516.1189165-1-lizetao1@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | ocfs2: fix memory leak in ocfs2_mount_volume() | expand |
Hi, Thanks for so detailed analysis. The patch almost looks good. A minor improvement, please see my comments inline. On 11/8/22 11:25 PM, Li Zetao wrote: > 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. > > Fixes: 9140db04ef18 ("ocfs2: recover orphans in offline slots during recovery and mount") > Signed-off-by: Li Zetao <lizetao1@huawei.com> > --- > 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 126671e6caed..3fb98b4569a2 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 42c993e53924..f8041aebe4ee 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; > > @@ -1822,12 +1823,14 @@ 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_truncate_log; > } > > ocfs2_super_unlock(osb, 1); > return 0; > > +out_truncate_log: I'd like define this label as 'out_check_volume', to indicate that it's the entry to do cleanup work of ocfs2_check_volume(). Other looks good to me. Thanks, Joseph > + ocfs2_free_replay_slots(osb); > out_system_inodes: > if (osb->local_alloc_state == OCFS2_LA_ENABLED) > ocfs2_shutdown_local_alloc(osb);
diff --git a/fs/ocfs2/journal.c b/fs/ocfs2/journal.c index 126671e6caed..3fb98b4569a2 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 42c993e53924..f8041aebe4ee 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; @@ -1822,12 +1823,14 @@ 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_truncate_log; } ocfs2_super_unlock(osb, 1); return 0; +out_truncate_log: + ocfs2_free_replay_slots(osb); out_system_inodes: if (osb->local_alloc_state == OCFS2_LA_ENABLED) ocfs2_shutdown_local_alloc(osb);
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. Fixes: 9140db04ef18 ("ocfs2: recover orphans in offline slots during recovery and mount") Signed-off-by: Li Zetao <lizetao1@huawei.com> --- fs/ocfs2/journal.c | 2 +- fs/ocfs2/journal.h | 1 + fs/ocfs2/super.c | 5 ++++- 3 files changed, 6 insertions(+), 2 deletions(-)