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This can result in an incorrect max_dentries value, causing readdir to stop early and omit directory entries. Cast nr_clusters to u64 before shifting to avoid the overflow. Signed-off-by: Yang Wen --- fs/exfat/dir.c | 2 +- fs/exfat/exfat_fs.h | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/exfat/dir.c b/fs/exfat/dir.c index 4fd4ec52b8c0..ce5251ba9589 100644 --- a/fs/exfat/dir.c +++ b/fs/exfat/dir.c @@ -87,7 +87,7 @@ static int exfat_readdir(struct inode *inode, loff_t *cpos, struct exfat_dir_ent exfat_bytes_to_cluster(sbi, i_size_read(inode)), ei->flags); dentries_per_clu = sbi->dentries_per_clu; - max_dentries = min(MAX_EXFAT_DENTRIES, + max_dentries = (unsigned int)min_t(u64, MAX_EXFAT_DENTRIES, exfat_cluster_to_dentries(sbi, sbi->num_clusters)); clu_offset = exfat_dentries_to_cluster(sbi, dentry); diff --git a/fs/exfat/exfat_fs.h b/fs/exfat/exfat_fs.h index 1f020b041a3d..fa30ab9d8564 100644 --- a/fs/exfat/exfat_fs.h +++ b/fs/exfat/exfat_fs.h @@ -487,10 +487,10 @@ static inline u32 exfat_dentries_to_bytes(u32 dentry) /* * helpers for cluster size to dentry size conversion. */ -static inline u32 exfat_cluster_to_dentries(struct exfat_sb_info *sbi, +static inline u64 exfat_cluster_to_dentries(struct exfat_sb_info *sbi, u32 nr_clusters) { - return nr_clusters << (sbi->cluster_size_bits - DENTRY_SIZE_BITS); + return (u64)nr_clusters << (sbi->cluster_size_bits - DENTRY_SIZE_BITS); } static inline u32 exfat_dentries_to_cluster(struct exfat_sb_info *sbi, -- 2.34.1