From 9aee8de970f18c2aaaa348e3de86c38e2d956c1d Mon Sep 17 00:00:00 2001 From: Shuhao Fu Date: Tue, 21 Oct 2025 16:42:28 +0800 Subject: [PATCH] exfat: fix refcount leak in exfat_find Fix refcount leaks in `exfat_find` related to `exfat_get_dentry_set`. Function `exfat_get_dentry_set` would increase the reference counter of `es->bh` on success. Therefore, `exfat_put_dentry_set` must be called after `exfat_get_dentry_set` to ensure refcount consistency. This patch relocate two checks to avoid possible leaks. Fixes: 82ebecdc74ff ("exfat: fix improper check of dentry.stream.valid_size") Fixes: 13940cef9549 ("exfat: add a check for invalid data size") Signed-off-by: Shuhao Fu Reviewed-by: Yuezhang Mo Signed-off-by: Namjae Jeon --- fs/exfat/namei.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/fs/exfat/namei.c b/fs/exfat/namei.c index 745dce29ddb53..dfe957493d49e 100644 --- a/fs/exfat/namei.c +++ b/fs/exfat/namei.c @@ -645,16 +645,6 @@ static int exfat_find(struct inode *dir, const struct qstr *qname, info->valid_size = le64_to_cpu(ep2->dentry.stream.valid_size); info->size = le64_to_cpu(ep2->dentry.stream.size); - if (info->valid_size < 0) { - exfat_fs_error(sb, "data valid size is invalid(%lld)", info->valid_size); - return -EIO; - } - - if (unlikely(EXFAT_B_TO_CLU_ROUND_UP(info->size, sbi) > sbi->used_clusters)) { - exfat_fs_error(sb, "data size is invalid(%lld)", info->size); - return -EIO; - } - info->start_clu = le32_to_cpu(ep2->dentry.stream.start_clu); if (!is_valid_cluster(sbi, info->start_clu) && info->size) { exfat_warn(sb, "start_clu is invalid cluster(0x%x)", @@ -692,6 +682,16 @@ static int exfat_find(struct inode *dir, const struct qstr *qname, 0); exfat_put_dentry_set(&es, false); + if (info->valid_size < 0) { + exfat_fs_error(sb, "data valid size is invalid(%lld)", info->valid_size); + return -EIO; + } + + if (unlikely(EXFAT_B_TO_CLU_ROUND_UP(info->size, sbi) > sbi->used_clusters)) { + exfat_fs_error(sb, "data size is invalid(%lld)", info->size); + return -EIO; + } + if (ei->start_clu == EXFAT_FREE_CLUSTER) { exfat_fs_error(sb, "non-zero size file starts with zero cluster (size : %llu, p_dir : %u, entry : 0x%08x)", -- 2.47.3