From nobody Sat Feb 7 10:18:26 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7C9082356DB for ; Wed, 21 May 2025 06:24:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747808655; cv=none; b=Y+0piYfzS5ACJVPe3p1+r4LDZwVnAFBgC121/6Vahbdag6ymMTwlRt010ISHf9q8z2ahnpUtf7aUrX2qX7ymGCKAHUbq8DpPoTQbZwsONK0+/icsOpQvMvmX7WyFJ6Wy6QNPfGZA0MF88i8gvAo+a/tJFKGnagO6rsqu5WanzbU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747808655; c=relaxed/simple; bh=KWJtTLrAUMHCEg+eR7U5ahOPzGqD4xEpJn0kY1SlmNY=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=f58QOGi3GWjDwmQ3ESwuClUXKtaLSmjvW64xueghwBrmODTnrfyG19m4V3ZbD8cuKgKyg1h2rJd1G5A0kXxWQZUABmGRhs47OGLTsm5HR+JgFHukf7PBcuIuP8KMPshFTTW3Rtz9vijHJXT37J6jzY9iUobj/wxoeSNZ4EdJqPM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Ktb1rYQd; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Ktb1rYQd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D1B82C4CEE4; Wed, 21 May 2025 06:24:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1747808655; bh=KWJtTLrAUMHCEg+eR7U5ahOPzGqD4xEpJn0kY1SlmNY=; h=From:To:Cc:Subject:Date:From; b=Ktb1rYQd6oqVdANjHbI9HrRY0EBKiMlLNQnyIkvcJzQtjwFpcZzjiedq768eksrvi eFH2OihsH8OACNtzpD9n84LZMxjyImDTK/BPm193X0y7Z746frRDi6+W6U7KqacFVY w2aCtpKxHv4Xymo4eYQkzVqFn85L4XGL1Z8MY7hi2mvy60WRhnkcZBP3qb0HTHaicY kQxP0GPUHyojlaq4HDjsYqdAOYITmOxyO/i7eCVkon1jDfZF49lqSYUN2MQCkxkNxK 3L7eTOWpDmdU/L+mECOi14AN25Vy+KQ9gQwKMq1n+ellAz8TRLhdHv5EqBFCy0EbB8 mi8tpuLXWwDGA== From: Chao Yu To: jaegeuk@kernel.org Cc: linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, Chao Yu , stable@kernel.org Subject: [PATCH] f2fs: fix to zero post-eof page Date: Wed, 21 May 2025 14:24:03 +0800 Message-ID: <20250521062403.742048-1-chao@kernel.org> X-Mailer: git-send-email 2.49.0.1143.g0be31eac6b-goog Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable fstest reports a f2fs bug: generic/363 42s ... [failed, exit status 1]- output mismatch (see /share/gi= t/fstests/results//generic/363.out.bad) --- tests/generic/363.out 2025-01-12 21:57:40.271440542 +0800 +++ /share/git/fstests/results//generic/363.out.bad 2025-05-19 19:55:58= .000000000 +0800 @@ -1,2 +1,78 @@ QA output created by 363 fsx -q -S 0 -e 1 -N 100000 +READ BAD DATA: offset =3D 0xd6fb, size =3D 0xf044, fname =3D /mnt/f2fs= /junk +OFFSET GOOD BAD RANGE +0x1540d 0x0000 0x2a25 0x0 +operation# (mod 256) for the bad data may be 37 +0x1540e 0x0000 0x2527 0x1 ... (Run 'diff -u /share/git/fstests/tests/generic/363.out /share/git/fstes= ts/results//generic/363.out.bad' to see the entire diff) Ran: generic/363 Failures: generic/363 Failed 1 of 1 tests The root cause is user can update post-eof page via mmap, however, f2fs mis= sed to zero post-eof page in below operations, so, once it expands i_size, then= it will include dummy data locates previous post-eof page, so during below operations, we need to zero post-eof page. Operations which can include dummy data after previous i_size after expandi= ng i_size: - write - mapwrite - truncate - fallocate * preallocate * zero_range * insert_range * collapse_range - clone_range (doesn=E2=80=99t support in f2fs) - copy_range (doesn=E2=80=99t support in f2fs) Cc: stable@kernel.org Signed-off-by: Chao Yu --- fs/f2fs/file.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index 6bd3de64f2a8..c7c66e591ebc 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -35,6 +35,17 @@ #include #include =20 +static void f2fs_zero_post_eof_page(struct inode *inode, loff_t new_size) +{ + loff_t old_size =3D i_size_read(inode); + + if (old_size > new_size) + return; + + /* zero or drop pages only in range of [old_size, new_size] */ + truncate_pagecache(inode, old_size); +} + static vm_fault_t f2fs_filemap_fault(struct vm_fault *vmf) { struct inode *inode =3D file_inode(vmf->vma->vm_file); @@ -105,6 +116,9 @@ static vm_fault_t f2fs_vm_page_mkwrite(struct vm_fault = *vmf) =20 file_update_time(vmf->vma->vm_file); filemap_invalidate_lock_shared(inode->i_mapping); + + f2fs_zero_post_eof_page(inode, (folio->index + 1) << PAGE_SHIFT); + folio_lock(folio); if (unlikely(folio->mapping !=3D inode->i_mapping || folio_pos(folio) > i_size_read(inode) || @@ -1109,6 +1123,8 @@ int f2fs_setattr(struct mnt_idmap *idmap, struct dent= ry *dentry, f2fs_down_write(&fi->i_gc_rwsem[WRITE]); filemap_invalidate_lock(inode->i_mapping); =20 + if (attr->ia_size > old_size) + f2fs_zero_post_eof_page(inode, old_size); truncate_setsize(inode, attr->ia_size); =20 if (attr->ia_size <=3D old_size) @@ -1227,6 +1243,8 @@ static int f2fs_punch_hole(struct inode *inode, loff_= t offset, loff_t len) if (ret) return ret; =20 + f2fs_zero_post_eof_page(inode, offset + len); + pg_start =3D ((unsigned long long) offset) >> PAGE_SHIFT; pg_end =3D ((unsigned long long) offset + len) >> PAGE_SHIFT; =20 @@ -1542,6 +1560,8 @@ static int f2fs_collapse_range(struct inode *inode, l= off_t offset, loff_t len) if (ret) return ret; =20 + f2fs_zero_post_eof_page(inode, offset + len); + ret =3D f2fs_do_collapse(inode, offset, len); if (ret) return ret; @@ -1631,6 +1651,8 @@ static int f2fs_zero_range(struct inode *inode, loff_= t offset, loff_t len, if (ret) return ret; =20 + f2fs_zero_post_eof_page(inode, offset + len); + pg_start =3D ((unsigned long long) offset) >> PAGE_SHIFT; pg_end =3D ((unsigned long long) offset + len) >> PAGE_SHIFT; =20 @@ -1754,6 +1776,8 @@ static int f2fs_insert_range(struct inode *inode, lof= f_t offset, loff_t len) if (ret) return ret; =20 + f2fs_zero_post_eof_page(inode, offset + len); + pg_start =3D offset >> PAGE_SHIFT; pg_end =3D (offset + len) >> PAGE_SHIFT; delta =3D pg_end - pg_start; @@ -1819,6 +1843,8 @@ static int f2fs_expand_inode_data(struct inode *inode= , loff_t offset, if (err) return err; =20 + f2fs_zero_post_eof_page(inode, offset + len); + f2fs_balance_fs(sbi, true); =20 pg_start =3D ((unsigned long long)offset) >> PAGE_SHIFT; @@ -4860,6 +4886,8 @@ static ssize_t f2fs_write_checks(struct kiocb *iocb, = struct iov_iter *from) err =3D file_modified(file); if (err) return err; + + f2fs_zero_post_eof_page(inode, iocb->ki_pos + iov_iter_count(from)); return count; } =20 --=20 2.49.0