From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: "Ernesto A. Fernández" <ernesto.mnd.fernandez@gmail.com>,
"Jens Axboe" <axboe@kernel.dk>, "Sasha Levin" <sashal@kernel.org>,
linux-fsdevel@vger.kernel.org
Subject: [PATCH AUTOSEL 4.9 16/27] direct-io: allow direct writes to empty inodes
Date: Thu, 14 Feb 2019 21:14:13 -0500 [thread overview]
Message-ID: <20190215021424.178979-16-sashal@kernel.org> (raw)
In-Reply-To: <20190215021424.178979-1-sashal@kernel.org>
From: Ernesto A. Fernández <ernesto.mnd.fernandez@gmail.com>
[ Upstream commit 8b9433eb4de3c26a9226c981c283f9f4896ae030 ]
On a DIO_SKIP_HOLES filesystem, the ->get_block() method is currently
not allowed to create blocks for an empty inode. This confusion comes
from trying to bit shift a negative number, so check the size of the
inode first.
The problem is most visible for hfsplus, because the fallback to
buffered I/O doesn't happen and the write fails with EIO. This is in
part the fault of the module, because it gives a wrong return value on
->get_block(); that will be fixed in a separate patch.
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Ernesto A. Fernández <ernesto.mnd.fernandez@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/direct-io.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/fs/direct-io.c b/fs/direct-io.c
index 07cc38ec66ca..fc90f0c33cbe 100644
--- a/fs/direct-io.c
+++ b/fs/direct-io.c
@@ -616,6 +616,7 @@ static int get_more_blocks(struct dio *dio, struct dio_submit *sdio,
unsigned long fs_count; /* Number of filesystem-sized blocks */
int create;
unsigned int i_blkbits = sdio->blkbits + sdio->blkfactor;
+ loff_t i_size;
/*
* If there was a memory error and we've overwritten all the
@@ -645,8 +646,8 @@ static int get_more_blocks(struct dio *dio, struct dio_submit *sdio,
*/
create = dio->op == REQ_OP_WRITE;
if (dio->flags & DIO_SKIP_HOLES) {
- if (fs_startblk <= ((i_size_read(dio->inode) - 1) >>
- i_blkbits))
+ i_size = i_size_read(dio->inode);
+ if (i_size && fs_startblk <= (i_size - 1) >> i_blkbits)
create = 0;
}
--
2.19.1
next prev parent reply other threads:[~2019-02-15 2:15 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-02-15 2:13 [PATCH AUTOSEL 4.9 01/27] drm/msm: Unblock writer if reader closes file Sasha Levin
2019-02-15 2:13 ` [PATCH AUTOSEL 4.9 02/27] ASoC: Intel: Haswell/Broadwell: fix setting for .dynamic field Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 03/27] ALSA: compress: prevent potential divide by zero bugs Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 04/27] thermal: int340x_thermal: Fix a NULL vs IS_ERR() check Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 05/27] usb: dwc3: gadget: synchronize_irq dwc irq in suspend Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 06/27] usb: dwc3: gadget: Fix the uninitialized link_state when udc starts Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 07/27] usb: gadget: Potential NULL dereference on allocation error Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 08/27] ASoC: dapm: change snprintf to scnprintf for possible overflow Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 09/27] ASoC: imx-audmux: " Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 10/27] ARC: fix __ffs return value to avoid build warnings Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 11/27] drivers: thermal: int340x_thermal: Fix sysfs race condition Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 12/27] mac80211: fix miscounting of ttl-dropped frames Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 13/27] locking/rwsem: Fix (possible) missed wakeup Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 14/27] libceph: avoid KEEPALIVE_PENDING races in ceph_con_keepalive() Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 15/27] serial: fsl_lpuart: fix maximum acceptable baud rate with over-sampling Sasha Levin
2019-02-15 2:14 ` Sasha Levin [this message]
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 17/27] scsi: csiostor: fix NULL pointer dereference in csio_vport_set_state() Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 18/27] net: altera_tse: fix connect_local_phy error path Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 19/27] sfc: suppress duplicate nvmem partition types in efx_ef10_mtd_probe Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 20/27] ax25: fix possible use-after-free Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 21/27] net: usb: asix: ax88772_bind return error when hw_reset fail Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 22/27] ibmveth: Do not process frames after calling napi_reschedule Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 23/27] mac80211: don't initiate TDLS connection if station is not associated to AP Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 24/27] mac80211: Add attribute aligned(2) to struct 'action' Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 25/27] cfg80211: extend range deviation for DMG Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 26/27] svm: Fix AVIC incomplete IPI emulation Sasha Levin
2019-02-15 2:14 ` [PATCH AUTOSEL 4.9 27/27] KVM: nSVM: clear events pending from svm_complete_interrupts() when exiting to L1 Sasha Levin
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