From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, Eugeniu Rosca <erosca@de.adit-jv.com>,
Geert Uytterhoeven <geert+renesas@glider.be>,
Vinod Koul <vkoul@kernel.org>, Sasha Levin <sashal@kernel.org>,
Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Subject: [PATCH 4.4 05/22] dmaengine: rcar-dmac: Reject zero-length slave DMA requests
Date: Mon, 5 Aug 2019 15:02:42 +0200 [thread overview]
Message-ID: <20190805124919.905295750@linuxfoundation.org> (raw)
In-Reply-To: <20190805124918.070468681@linuxfoundation.org>
[ Upstream commit 78efb76ab4dfb8f74f290ae743f34162cd627f19 ]
While the .device_prep_slave_sg() callback rejects empty scatterlists,
it still accepts single-entry scatterlists with a zero-length segment.
These may happen if a driver calls dmaengine_prep_slave_single() with a
zero len parameter. The corresponding DMA request will never complete,
leading to messages like:
rcar-dmac e7300000.dma-controller: Channel Address Error happen
and DMA timeouts.
Although requesting a zero-length DMA request is a driver bug, rejecting
it early eases debugging. Note that the .device_prep_dma_memcpy()
callback already rejects requests to copy zero bytes.
Reported-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Analyzed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/dma/sh/rcar-dmac.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/dma/sh/rcar-dmac.c b/drivers/dma/sh/rcar-dmac.c
index 2b36d1c63aa5f..956189a1ba81c 100644
--- a/drivers/dma/sh/rcar-dmac.c
+++ b/drivers/dma/sh/rcar-dmac.c
@@ -1030,7 +1030,7 @@ rcar_dmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
dma_addr_t dev_addr;
/* Someone calling slave DMA on a generic channel? */
- if (rchan->mid_rid < 0 || !sg_len) {
+ if (rchan->mid_rid < 0 || !sg_len || !sg_dma_len(sgl)) {
dev_warn(chan->device->dev,
"%s: bad parameter: len=%d, id=%d\n",
__func__, sg_len, rchan->mid_rid);
--
2.20.1
next prev parent reply other threads:[~2019-08-05 13:17 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-05 13:02 [PATCH 4.4 00/22] 4.4.188-stable review Greg Kroah-Hartman
2019-08-05 13:02 ` [PATCH 4.4 01/22] ARM: riscpc: fix DMA Greg Kroah-Hartman
2019-08-05 13:02 ` [PATCH 4.4 02/22] ARM: dts: rockchip: Mark that the rk3288 timer might stop in suspend Greg Kroah-Hartman
2019-08-05 13:02 ` [PATCH 4.4 03/22] kernel/module.c: Only return -EEXIST for modules that have finished loading Greg Kroah-Hartman
2019-08-05 13:02 ` [PATCH 4.4 04/22] MIPS: lantiq: Fix bitfield masking Greg Kroah-Hartman
2019-08-05 13:02 ` Greg Kroah-Hartman [this message]
2019-08-05 13:02 ` [PATCH 4.4 06/22] fs/adfs: super: fix use-after-free bug Greg Kroah-Hartman
2019-08-05 13:02 ` [PATCH 4.4 07/22] btrfs: fix minimum number of chunk errors for DUP Greg Kroah-Hartman
2019-08-05 13:02 ` [PATCH 4.4 08/22] ceph: fix improper use of smp_mb__before_atomic() Greg Kroah-Hartman
2019-08-05 13:02 ` [PATCH 4.4 09/22] scsi: zfcp: fix GCC compiler warning emitted with -Wmaybe-uninitialized Greg Kroah-Hartman
2019-08-05 13:02 ` [PATCH 4.4 10/22] ACPI: fix false-positive -Wuninitialized warning Greg Kroah-Hartman
2019-08-05 13:02 ` [PATCH 4.4 11/22] be2net: Signal that the device cannot transmit during reconfiguration Greg Kroah-Hartman
2019-08-05 13:02 ` [PATCH 4.4 12/22] x86/apic: Silence -Wtype-limits compiler warnings Greg Kroah-Hartman
2019-08-05 13:02 ` [PATCH 4.4 13/22] x86: math-emu: Hide clang warnings for 16-bit overflow Greg Kroah-Hartman
2019-08-05 13:02 ` [PATCH 4.4 14/22] mm/cma.c: fail if fixed declaration cant be honored Greg Kroah-Hartman
2019-08-05 13:02 ` [PATCH 4.4 15/22] coda: add error handling for fget Greg Kroah-Hartman
2019-08-05 13:02 ` [PATCH 4.4 16/22] coda: fix build using bare-metal toolchain Greg Kroah-Hartman
2019-08-05 13:02 ` [PATCH 4.4 17/22] uapi linux/coda_psdev.h: move upc_req definition from uapi to kernel side headers Greg Kroah-Hartman
2019-08-05 13:02 ` [PATCH 4.4 18/22] ipc/mqueue.c: only perform resource calculation if user valid Greg Kroah-Hartman
2019-08-05 13:02 ` [PATCH 4.4 19/22] x86/kvm: Dont call kvm_spurious_fault() from .fixup Greg Kroah-Hartman
2019-08-05 13:02 ` [PATCH 4.4 20/22] selinux: fix memory leak in policydb_init() Greg Kroah-Hartman
2019-08-05 13:02 ` [PATCH 4.4 21/22] s390/dasd: fix endless loop after read unit address configuration Greg Kroah-Hartman
2019-08-05 13:02 ` [PATCH 4.4 22/22] xen/swiotlb: fix condition for calling xen_destroy_contiguous_region() Greg Kroah-Hartman
2019-08-05 17:35 ` [PATCH 4.4 00/22] 4.4.188-stable review kernelci.org bot
2019-08-06 1:14 ` shuah
2019-08-06 7:26 ` Naresh Kamboju
2019-08-06 15:48 ` Guenter Roeck
2019-08-06 18:28 ` Jon Hunter
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