From: Ritesh Harjani (IBM) Date: Mon, 10 Jul 2023 21:12:22 +0000 (-0700) Subject: iomap: Fix possible overflow condition in iomap_write_delalloc_scan X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=eee2d2e6ea5550118170dbd5bb1316ceb38455fb;p=linux.git iomap: Fix possible overflow condition in iomap_write_delalloc_scan folio_next_index() returns an unsigned long value which left shifted by PAGE_SHIFT could possibly cause an overflow on 32-bit system. Instead use folio_pos(folio) + folio_size(folio), which does this correctly. Suggested-by: Matthew Wilcox Signed-off-by: Ritesh Harjani (IBM) Reviewed-by: Darrick J. Wong --- diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index 85159e5b3d1d4..38e95302bd6ad 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -934,7 +934,7 @@ static int iomap_write_delalloc_scan(struct inode *inode, * the end of this data range, not the end of the folio. */ *punch_start_byte = min_t(loff_t, end_byte, - folio_next_index(folio) << PAGE_SHIFT); + folio_pos(folio) + folio_size(folio)); } /* move offset to start of next folio in range */