From 8ff006e57ad3a25f909c456d053aa498b6673a39 Mon Sep 17 00:00:00 2001 From: Namjae Jeon Date: Tue, 29 Sep 2020 09:09:49 +0900 Subject: exfat: fix use of uninitialized spinlock on error path syzbot reported warning message: Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1d6/0x29e lib/dump_stack.c:118 register_lock_class+0xf06/0x1520 kernel/locking/lockdep.c:893 __lock_acquire+0xfd/0x2ae0 kernel/locking/lockdep.c:4320 lock_acquire+0x148/0x720 kernel/locking/lockdep.c:5029 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:354 [inline] exfat_cache_inval_inode+0x30/0x280 fs/exfat/cache.c:226 exfat_evict_inode+0x124/0x270 fs/exfat/inode.c:660 evict+0x2bb/0x6d0 fs/inode.c:576 exfat_fill_super+0x1e07/0x27d0 fs/exfat/super.c:681 get_tree_bdev+0x3e9/0x5f0 fs/super.c:1342 vfs_get_tree+0x88/0x270 fs/super.c:1547 do_new_mount fs/namespace.c:2875 [inline] path_mount+0x179d/0x29e0 fs/namespace.c:3192 do_mount fs/namespace.c:3205 [inline] __do_sys_mount fs/namespace.c:3413 [inline] __se_sys_mount+0x126/0x180 fs/namespace.c:3390 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 If exfat_read_root() returns an error, spinlock is used in exfat_evict_inode() without initialization. This patch combines exfat_cache_init_inode() with exfat_inode_init_once() to initialize spinlock by slab constructor. Fixes: c35b6810c495 ("exfat: add exfat cache") Cc: stable@vger.kernel.org # v5.7+ Reported-by: syzbot Signed-off-by: Namjae Jeon --- fs/exfat/super.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'fs/exfat/super.c') diff --git a/fs/exfat/super.c b/fs/exfat/super.c index 3b6a1659892f..60b941ba557b 100644 --- a/fs/exfat/super.c +++ b/fs/exfat/super.c @@ -376,7 +376,6 @@ static int exfat_read_root(struct inode *inode) inode->i_mtime = inode->i_atime = inode->i_ctime = ei->i_crtime = current_time(inode); exfat_truncate_atime(&inode->i_atime); - exfat_cache_init_inode(inode); return 0; } @@ -763,6 +762,10 @@ static void exfat_inode_init_once(void *foo) { struct exfat_inode_info *ei = (struct exfat_inode_info *)foo; + spin_lock_init(&ei->cache_lru_lock); + ei->nr_caches = 0; + ei->cache_valid_id = EXFAT_CACHE_VALID + 1; + INIT_LIST_HEAD(&ei->cache_lru); INIT_HLIST_NODE(&ei->i_hash_fat); inode_init_once(&ei->vfs_inode); } -- cgit v1.2.3