[PATCH] f2fs: fix slab leak of rpages pointer
From: Jaegeuk Kim
Date: Wed Sep 23 2020 - 04:45:17 EST
This fixes the below mem leak.
[ 130.157600] =============================================================================
[ 130.159662] BUG f2fs_page_array_entry-252:16 (Tainted: G W O ): Objects remaining in f2fs_page_array_entry-252:16 on __kmem_cache_shutdown()
[ 130.162742] -----------------------------------------------------------------------------
[ 130.162742]
[ 130.164979] Disabling lock debugging due to kernel taint
[ 130.166188] INFO: Slab 0x000000009f5a52d2 objects=22 used=4 fp=0x00000000ba72c3e9 flags=0xfffffc0010200
[ 130.168269] CPU: 7 PID: 3560 Comm: umount Tainted: G B W O 5.9.0-rc4+ #35
[ 130.170019] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1 04/01/2014
[ 130.171941] Call Trace:
[ 130.172528] dump_stack+0x74/0x9a
[ 130.173298] slab_err+0xb7/0xdc
[ 130.174044] ? kernel_poison_pages+0xc0/0xc0
[ 130.175065] ? on_each_cpu_cond_mask+0x48/0x90
[ 130.176096] __kmem_cache_shutdown.cold+0x34/0x141
[ 130.177190] kmem_cache_destroy+0x59/0x100
[ 130.178223] f2fs_destroy_page_array_cache+0x15/0x20 [f2fs]
[ 130.179527] f2fs_put_super+0x1bc/0x380 [f2fs]
[ 130.180538] generic_shutdown_super+0x72/0x110
[ 130.181547] kill_block_super+0x27/0x50
[ 130.182438] kill_f2fs_super+0x76/0xe0 [f2fs]
[ 130.183448] deactivate_locked_super+0x3b/0x80
[ 130.184456] deactivate_super+0x3e/0x50
[ 130.185363] cleanup_mnt+0x109/0x160
[ 130.186179] __cleanup_mnt+0x12/0x20
[ 130.187003] task_work_run+0x70/0xb0
[ 130.187841] exit_to_user_mode_prepare+0x18f/0x1b0
[ 130.188917] syscall_exit_to_user_mode+0x31/0x170
[ 130.189989] do_syscall_64+0x45/0x90
[ 130.190828] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 130.191986] RIP: 0033:0x7faf868ea2eb
[ 130.192815] Code: 7b 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 90 f3 0f 1e fa 31 f6 e9 05 00 00 00 0f 1f 44 00 00 f3 0f 1e fa b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 75 7b 0c 00 f7 d8 64 89 01
[ 130.196872] RSP: 002b:00007fffb7edb478 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
[ 130.198494] RAX: 0000000000000000 RBX: 00007faf86a18204 RCX: 00007faf868ea2eb
[ 130.201021] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000055971df71c50
[ 130.203415] RBP: 000055971df71a40 R08: 0000000000000000 R09: 00007fffb7eda1f0
[ 130.205772] R10: 00007faf86a04339 R11: 0000000000000246 R12: 000055971df71c50
[ 130.208150] R13: 0000000000000000 R14: 000055971df71b38 R15: 0000000000000000
[ 130.210515] INFO: Object 0x00000000a980843a @offset=744
[ 130.212476] INFO: Allocated in page_array_alloc+0x3d/0xe0 [f2fs] age=1572 cpu=0 pid=3297
[ 130.215030] __slab_alloc+0x20/0x40
[ 130.216566] kmem_cache_alloc+0x2a0/0x2e0
[ 130.218217] page_array_alloc+0x3d/0xe0 [f2fs]
[ 130.219940] f2fs_init_compress_ctx+0x1f/0x40 [f2fs]
[ 130.221736] f2fs_write_cache_pages+0x3db/0x860 [f2fs]
[ 130.223591] f2fs_write_data_pages+0x2c9/0x300 [f2fs]
[ 130.225414] do_writepages+0x43/0xd0
[ 130.226907] __filemap_fdatawrite_range+0xd5/0x110
[ 130.228632] filemap_write_and_wait_range+0x48/0xb0
[ 130.230336] __generic_file_write_iter+0x18a/0x1d0
[ 130.232035] f2fs_file_write_iter+0x226/0x550 [f2fs]
[ 130.233737] new_sync_write+0x113/0x1a0
[ 130.235204] vfs_write+0x1a6/0x200
[ 130.236579] ksys_write+0x67/0xe0
[ 130.237898] __x64_sys_write+0x1a/0x20
[ 130.239309] do_syscall_64+0x38/0x90
Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
---
fs/f2fs/compress.c | 2 +-
fs/f2fs/data.c | 2 ++
2 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c
index 10a9f39b9d6a2..f086ac43ca825 100644
--- a/fs/f2fs/compress.c
+++ b/fs/f2fs/compress.c
@@ -159,7 +159,7 @@ struct page *f2fs_compress_control_page(struct page *page)
int f2fs_init_compress_ctx(struct compress_ctx *cc)
{
- if (cc->nr_rpages)
+ if (cc->rpages)
return 0;
cc->rpages = page_array_alloc(cc->inode);
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index db020a74fd849..ee87407602fa7 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -3129,6 +3129,8 @@ static int f2fs_write_cache_pages(struct address_space *mapping,
retry = 0;
}
}
+ if (f2fs_compressed_file(inode))
+ f2fs_destroy_compress_ctx(&cc);
#endif
if (retry) {
index = 0;
--
2.28.0.681.g6f77f65b4e-goog