From mboxrd@z Thu Jan 1 00:00:00 1970 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 AD8FA21B441; Fri, 4 Oct 2024 18:18:54 +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=1728065934; cv=none; b=UzHm215PLSqfC3ot4AEH6RRgt8qei0WrM9L2HyKNl7cRV2+jRruzESJRfLP7Q9XGc6tiIkrDHqrMd9zgLcmbhQUftEw3qQ5fqq4G0sTajJfjFSrAJN89zgSvz3ekUeFG6LbIDrYa63M4NLH3z+H+1tjru4546/hn7O4tmAYZThA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728065934; c=relaxed/simple; bh=MJzmWT6AHwLeoV55B/mEguR8hVitLpdD11bbWACmNpk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=NTXPXy8pb9JBeVMSO06Z9fH57wmCLBk52pGSUq029CA3ibPhhnmnmr0201XBdMGiSLVLSJEyKSj71wP5dedMo5W96aymAotQ1q8hBKzVIkhfpuXGBuUTourguSTSVi9Ctd3PotqFTCFmf6l65Ku4Y+fKJQUiUBq6NeBqrWWZCxk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=VN8qgzWA; 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="VN8qgzWA" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0A7F2C4CEC6; Fri, 4 Oct 2024 18:18:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1728065934; bh=MJzmWT6AHwLeoV55B/mEguR8hVitLpdD11bbWACmNpk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VN8qgzWA0WStPt8o8tO0khDSlBXxWyUz6c707Li+ycx/Mwi3Hn138Ao4YKRT/st/E GJYcnSTL6a4giwKQB8XgxD+SsbqjfbaEEB48BuwNUkHmO0GKcpASUaUTf04MH+hlaM 4oriUhzuk7Z6/j2Jt6LjX7jkdSt6hB87X01PV3aKy3ZnQvze6TBIESjf53yBkjk0Qo QymYANL/Av3+rlV5/xsj5MoBuMOXy88ZbUVReZrHvGNFPOqq3xa1vSyREz72+nO83W ARpwpbhXPZ66ZPsTjru61geZAEk6V9zhQSLUUhzUNlrgJLNUawgEnhAqX8p7EAbYg9 ozOxjg9q+QEXw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Pankaj Raghav , Hannes Reinecke , "Darrick J . Wong" , Dave Chinner , Daniel Gomez , Christian Brauner , Sasha Levin , linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH AUTOSEL 6.11 14/76] iomap: fix iomap_dio_zero() for fs bs > system page size Date: Fri, 4 Oct 2024 14:16:31 -0400 Message-ID: <20241004181828.3669209-14-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20241004181828.3669209-1-sashal@kernel.org> References: <20241004181828.3669209-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.11.2 Content-Transfer-Encoding: 8bit From: Pankaj Raghav [ Upstream commit 10553a91652d995274da63fc317470f703765081 ] iomap_dio_zero() will pad a fs block with zeroes if the direct IO size < fs block size. iomap_dio_zero() has an implicit assumption that fs block size < page_size. This is true for most filesystems at the moment. If the block size > page size, this will send the contents of the page next to zero page(as len > PAGE_SIZE) to the underlying block device, causing FS corruption. iomap is a generic infrastructure and it should not make any assumptions about the fs block size and the page size of the system. Signed-off-by: Pankaj Raghav Link: https://lore.kernel.org/r/20240822135018.1931258-7-kernel@pankajraghav.com Reviewed-by: Hannes Reinecke Reviewed-by: Darrick J. Wong Reviewed-by: Dave Chinner Reviewed-by: Daniel Gomez Signed-off-by: Christian Brauner Signed-off-by: Sasha Levin --- fs/iomap/buffered-io.c | 4 ++-- fs/iomap/direct-io.c | 45 ++++++++++++++++++++++++++++++++++++------ 2 files changed, 41 insertions(+), 8 deletions(-) diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index f420c53d86acc..d745f718bcde8 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -2007,10 +2007,10 @@ iomap_writepages(struct address_space *mapping, struct writeback_control *wbc, } EXPORT_SYMBOL_GPL(iomap_writepages); -static int __init iomap_init(void) +static int __init iomap_buffered_init(void) { return bioset_init(&iomap_ioend_bioset, 4 * (PAGE_SIZE / SECTOR_SIZE), offsetof(struct iomap_ioend, io_bio), BIOSET_NEED_BVECS); } -fs_initcall(iomap_init); +fs_initcall(iomap_buffered_init); diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c index f3b43d223a46e..c02b266bba525 100644 --- a/fs/iomap/direct-io.c +++ b/fs/iomap/direct-io.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include "trace.h" @@ -27,6 +28,13 @@ #define IOMAP_DIO_WRITE (1U << 30) #define IOMAP_DIO_DIRTY (1U << 31) +/* + * Used for sub block zeroing in iomap_dio_zero() + */ +#define IOMAP_ZERO_PAGE_SIZE (SZ_64K) +#define IOMAP_ZERO_PAGE_ORDER (get_order(IOMAP_ZERO_PAGE_SIZE)) +static struct page *zero_page; + struct iomap_dio { struct kiocb *iocb; const struct iomap_dio_ops *dops; @@ -232,13 +240,20 @@ void iomap_dio_bio_end_io(struct bio *bio) } EXPORT_SYMBOL_GPL(iomap_dio_bio_end_io); -static void iomap_dio_zero(const struct iomap_iter *iter, struct iomap_dio *dio, +static int iomap_dio_zero(const struct iomap_iter *iter, struct iomap_dio *dio, loff_t pos, unsigned len) { struct inode *inode = file_inode(dio->iocb->ki_filp); - struct page *page = ZERO_PAGE(0); struct bio *bio; + if (!len) + return 0; + /* + * Max block size supported is 64k + */ + if (WARN_ON_ONCE(len > IOMAP_ZERO_PAGE_SIZE)) + return -EINVAL; + bio = iomap_dio_alloc_bio(iter, dio, 1, REQ_OP_WRITE | REQ_SYNC | REQ_IDLE); fscrypt_set_bio_crypt_ctx(bio, inode, pos >> inode->i_blkbits, GFP_KERNEL); @@ -246,8 +261,9 @@ static void iomap_dio_zero(const struct iomap_iter *iter, struct iomap_dio *dio, bio->bi_private = dio; bio->bi_end_io = iomap_dio_bio_end_io; - __bio_add_page(bio, page, len, 0); + __bio_add_page(bio, zero_page, len, 0); iomap_dio_submit_bio(iter, dio, bio, pos); + return 0; } /* @@ -356,8 +372,10 @@ static loff_t iomap_dio_bio_iter(const struct iomap_iter *iter, if (need_zeroout) { /* zero out from the start of the block to the write offset */ pad = pos & (fs_block_size - 1); - if (pad) - iomap_dio_zero(iter, dio, pos - pad, pad); + + ret = iomap_dio_zero(iter, dio, pos - pad, pad); + if (ret) + goto out; } /* @@ -431,7 +449,8 @@ static loff_t iomap_dio_bio_iter(const struct iomap_iter *iter, /* zero out from the end of the write to the end of the block */ pad = pos & (fs_block_size - 1); if (pad) - iomap_dio_zero(iter, dio, pos, fs_block_size - pad); + ret = iomap_dio_zero(iter, dio, pos, + fs_block_size - pad); } out: /* Undo iter limitation to current extent */ @@ -753,3 +772,17 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter, return iomap_dio_complete(dio); } EXPORT_SYMBOL_GPL(iomap_dio_rw); + +static int __init iomap_dio_init(void) +{ + zero_page = alloc_pages(GFP_KERNEL | __GFP_ZERO, + IOMAP_ZERO_PAGE_ORDER); + + if (!zero_page) + return -ENOMEM; + + set_memory_ro((unsigned long)page_address(zero_page), + 1U << IOMAP_ZERO_PAGE_ORDER); + return 0; +} +fs_initcall(iomap_dio_init); -- 2.43.0