* [PATCH AUTOSEL 4.4 05/29] media: b2c2: Add missing check in flexcop_pci_isr:
[not found] <20220118030822.1955469-1-sashal@kernel.org>
@ 2022-01-18 3:07 ` Sasha Levin
2022-01-18 3:08 ` [PATCH AUTOSEL 4.4 10/29] media: saa7146: hexium_orion: Fix a NULL pointer dereference in hexium_attach() Sasha Levin
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Sasha Levin @ 2022-01-18 3:07 UTC (permalink / raw)
To: linux-kernel, stable
Cc: Zheyu Ma, Mauro Carvalho Chehab, Sasha Levin, mchehab, sean, arnd,
linux-media
From: Zheyu Ma <zheyuma97@gmail.com>
[ Upstream commit b13203032e679674c7c518f52a7ec0801ca3a829 ]
A out-of-bounds bug can be triggered by an interrupt, the reason for
this bug is the lack of checking of register values.
In flexcop_pci_isr, the driver reads value from a register and uses it as
a dma address. Finally, this address will be passed to the count parameter
of find_next_packet. If this value is larger than the size of dma, the
index of buffer will be out-of-bounds.
Fix this by adding a check after reading the value of the register.
The following KASAN report reveals it:
BUG: KASAN: slab-out-of-bounds in find_next_packet
drivers/media/dvb-core/dvb_demux.c:528 [inline]
BUG: KASAN: slab-out-of-bounds in _dvb_dmx_swfilter
drivers/media/dvb-core/dvb_demux.c:572 [inline]
BUG: KASAN: slab-out-of-bounds in dvb_dmx_swfilter+0x3fa/0x420
drivers/media/dvb-core/dvb_demux.c:603
Read of size 1 at addr ffff8880608c00a0 by task swapper/2/0
CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.19.177-gdba4159c14ef #25
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0xec/0x156 lib/dump_stack.c:118
print_address_description+0x78/0x290 mm/kasan/report.c:256
kasan_report_error mm/kasan/report.c:354 [inline]
kasan_report+0x25b/0x380 mm/kasan/report.c:412
__asan_report_load1_noabort+0x19/0x20 mm/kasan/report.c:430
find_next_packet drivers/media/dvb-core/dvb_demux.c:528 [inline]
_dvb_dmx_swfilter drivers/media/dvb-core/dvb_demux.c:572 [inline]
dvb_dmx_swfilter+0x3fa/0x420 drivers/media/dvb-core/dvb_demux.c:603
flexcop_pass_dmx_data+0x2e/0x40 drivers/media/common/b2c2/flexcop.c:167
flexcop_pci_isr+0x3d1/0x5d0 drivers/media/pci/b2c2/flexcop-pci.c:212
__handle_irq_event_percpu+0xfb/0x770 kernel/irq/handle.c:149
handle_irq_event_percpu+0x79/0x150 kernel/irq/handle.c:189
handle_irq_event+0xac/0x140 kernel/irq/handle.c:206
handle_fasteoi_irq+0x232/0x5c0 kernel/irq/chip.c:725
generic_handle_irq_desc include/linux/irqdesc.h:155 [inline]
handle_irq+0x230/0x3a0 arch/x86/kernel/irq_64.c:87
do_IRQ+0xa7/0x1e0 arch/x86/kernel/irq.c:247
common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:670
</IRQ>
RIP: 0010:native_safe_halt+0x28/0x30 arch/x86/include/asm/irqflags.h:61
Code: 00 00 55 be 04 00 00 00 48 c7 c7 00 62 2f 8c 48 89 e5 e8 fb 31
e8 f8 8b 05 75 4f 8e 03 85 c0 7e 07 0f 00 2d 8a 61 66 00 fb f4 <5d> c3
90 90 90 90 90 90 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 41
RSP: 0018:ffff88806b71fcc8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffde
RAX: 0000000000000000 RBX: ffffffff8bde44c8 RCX: ffffffff88a11285
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff8c2f6200
RBP: ffff88806b71fcc8 R08: fffffbfff185ec40 R09: fffffbfff185ec40
R10: 0000000000000001 R11: fffffbfff185ec40 R12: 0000000000000002
R13: ffffffff8be9d6e0 R14: 0000000000000000 R15: 0000000000000000
arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline]
default_idle+0x6f/0x360 arch/x86/kernel/process.c:557
arch_cpu_idle+0xf/0x20 arch/x86/kernel/process.c:548
default_idle_call+0x3b/0x60 kernel/sched/idle.c:93
cpuidle_idle_call kernel/sched/idle.c:153 [inline]
do_idle+0x2ab/0x3c0 kernel/sched/idle.c:263
cpu_startup_entry+0xcb/0xe0 kernel/sched/idle.c:369
start_secondary+0x3b8/0x4e0 arch/x86/kernel/smpboot.c:271
secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243
Allocated by task 1:
save_stack+0x43/0xd0 mm/kasan/kasan.c:448
set_track mm/kasan/kasan.c:460 [inline]
kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:553
kasan_slab_alloc+0x11/0x20 mm/kasan/kasan.c:490
slab_post_alloc_hook mm/slab.h:445 [inline]
slab_alloc_node mm/slub.c:2741 [inline]
slab_alloc mm/slub.c:2749 [inline]
kmem_cache_alloc+0xeb/0x280 mm/slub.c:2754
kmem_cache_zalloc include/linux/slab.h:699 [inline]
__kernfs_new_node+0xe2/0x6f0 fs/kernfs/dir.c:633
kernfs_new_node+0x9a/0x120 fs/kernfs/dir.c:693
__kernfs_create_file+0x5f/0x340 fs/kernfs/file.c:992
sysfs_add_file_mode_ns+0x22a/0x4e0 fs/sysfs/file.c:306
create_files fs/sysfs/group.c:63 [inline]
internal_create_group+0x34e/0xc30 fs/sysfs/group.c:147
sysfs_create_group fs/sysfs/group.c:173 [inline]
sysfs_create_groups+0x9c/0x140 fs/sysfs/group.c:200
driver_add_groups+0x3e/0x50 drivers/base/driver.c:129
bus_add_driver+0x3a5/0x790 drivers/base/bus.c:684
driver_register+0x1cd/0x410 drivers/base/driver.c:170
__pci_register_driver+0x197/0x200 drivers/pci/pci-driver.c:1411
cx88_audio_pci_driver_init+0x23/0x25 drivers/media/pci/cx88/cx88-alsa.c:
1017
do_one_initcall+0xe0/0x610 init/main.c:884
do_initcall_level init/main.c:952 [inline]
do_initcalls init/main.c:960 [inline]
do_basic_setup init/main.c:978 [inline]
kernel_init_freeable+0x4d0/0x592 init/main.c:1145
kernel_init+0x18/0x190 init/main.c:1062
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Freed by task 0:
(stack is not available)
The buggy address belongs to the object at ffff8880608c0000
which belongs to the cache kernfs_node_cache of size 160
The buggy address is located 0 bytes to the right of
160-byte region [ffff8880608c0000, ffff8880608c00a0)
The buggy address belongs to the page:
page:ffffea0001823000 count:1 mapcount:0 mapping:ffff88806bed1e00
index:0x0 compound_mapcount: 0
flags: 0x100000000008100(slab|head)
raw: 0100000000008100 dead000000000100 dead000000000200 ffff88806bed1e00
raw: 0000000000000000 0000000000240024 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff8880608bff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff8880608c0000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880608c0080: 00 00 00 00 fc fc fc fc fc fc fc fc 00 00 00 00
^
ffff8880608c0100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff8880608c0180: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00
==================================================================
Link: https://lore.kernel.org/linux-media/1620723603-30912-1-git-send-email-zheyuma97@gmail.com
Reported-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/media/pci/b2c2/flexcop-pci.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/media/pci/b2c2/flexcop-pci.c b/drivers/media/pci/b2c2/flexcop-pci.c
index 8b5e0b3a92a0c..2f496c05a3316 100644
--- a/drivers/media/pci/b2c2/flexcop-pci.c
+++ b/drivers/media/pci/b2c2/flexcop-pci.c
@@ -184,6 +184,8 @@ static irqreturn_t flexcop_pci_isr(int irq, void *dev_id)
dma_addr_t cur_addr =
fc->read_ibi_reg(fc,dma1_008).dma_0x8.dma_cur_addr << 2;
u32 cur_pos = cur_addr - fc_pci->dma[0].dma_addr0;
+ if (cur_pos > fc_pci->dma[0].size * 2)
+ goto error;
deb_irq("%u irq: %08x cur_addr: %llx: cur_pos: %08x, "
"last_cur_pos: %08x ",
@@ -225,6 +227,7 @@ static irqreturn_t flexcop_pci_isr(int irq, void *dev_id)
ret = IRQ_NONE;
}
+error:
spin_unlock_irqrestore(&fc_pci->irq_lock, flags);
return ret;
}
--
2.34.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH AUTOSEL 4.4 10/29] media: saa7146: hexium_orion: Fix a NULL pointer dereference in hexium_attach()
[not found] <20220118030822.1955469-1-sashal@kernel.org>
2022-01-18 3:07 ` [PATCH AUTOSEL 4.4 05/29] media: b2c2: Add missing check in flexcop_pci_isr: Sasha Levin
@ 2022-01-18 3:08 ` Sasha Levin
2022-01-18 3:08 ` [PATCH AUTOSEL 4.4 11/29] media: m920x: don't use stack on USB reads Sasha Levin
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Sasha Levin @ 2022-01-18 3:08 UTC (permalink / raw)
To: linux-kernel, stable
Cc: Zhou Qingyang, Hans Verkuil, Mauro Carvalho Chehab, Sasha Levin,
hverkuil, mchehab, linux-media
From: Zhou Qingyang <zhou1615@umn.edu>
[ Upstream commit 348df8035301dd212e3cc2860efe4c86cb0d3303 ]
In hexium_attach(dev, info), saa7146_vv_init() is called to allocate
a new memory for dev->vv_data. In hexium_detach(), saa7146_vv_release()
will be called and there is a dereference of dev->vv_data in
saa7146_vv_release(), which could lead to a NULL pointer dereference
on failure of saa7146_vv_init() according to the following logic.
Both hexium_attach() and hexium_detach() are callback functions of
the variable 'extension', so there exists a possible call chain directly
from hexium_attach() to hexium_detach():
hexium_attach(dev, info) -- fail to alloc memory to dev->vv_data
| in saa7146_vv_init().
|
|
hexium_detach() -- a dereference of dev->vv_data in saa7146_vv_release()
Fix this bug by adding a check of saa7146_vv_init().
This bug was found by a static analyzer. The analysis employs
differential checking to identify inconsistent security operations
(e.g., checks or kfrees) between two code paths and confirms that the
inconsistent operations are not recovered in the current function or
the callers, so they constitute bugs.
Note that, as a bug found by static analysis, it can be a false
positive or hard to trigger. Multiple researchers have cross-reviewed
the bug.
Builds with CONFIG_VIDEO_HEXIUM_ORION=m show no new warnings,
and our static analyzer no longer warns about this code.
Signed-off-by: Zhou Qingyang <zhou1615@umn.edu>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/media/pci/saa7146/hexium_orion.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/drivers/media/pci/saa7146/hexium_orion.c b/drivers/media/pci/saa7146/hexium_orion.c
index 214396b1ca73c..2f3b4e01ff289 100644
--- a/drivers/media/pci/saa7146/hexium_orion.c
+++ b/drivers/media/pci/saa7146/hexium_orion.c
@@ -366,10 +366,16 @@ static struct saa7146_ext_vv vv_data;
static int hexium_attach(struct saa7146_dev *dev, struct saa7146_pci_extension_data *info)
{
struct hexium *hexium = (struct hexium *) dev->ext_priv;
+ int ret;
DEB_EE("\n");
- saa7146_vv_init(dev, &vv_data);
+ ret = saa7146_vv_init(dev, &vv_data);
+ if (ret) {
+ pr_err("Error in saa7146_vv_init()\n");
+ return ret;
+ }
+
vv_data.vid_ops.vidioc_enum_input = vidioc_enum_input;
vv_data.vid_ops.vidioc_g_input = vidioc_g_input;
vv_data.vid_ops.vidioc_s_input = vidioc_s_input;
--
2.34.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH AUTOSEL 4.4 11/29] media: m920x: don't use stack on USB reads
[not found] <20220118030822.1955469-1-sashal@kernel.org>
2022-01-18 3:07 ` [PATCH AUTOSEL 4.4 05/29] media: b2c2: Add missing check in flexcop_pci_isr: Sasha Levin
2022-01-18 3:08 ` [PATCH AUTOSEL 4.4 10/29] media: saa7146: hexium_orion: Fix a NULL pointer dereference in hexium_attach() Sasha Levin
@ 2022-01-18 3:08 ` Sasha Levin
2022-01-20 10:26 ` Pavel Machek
2022-01-18 3:08 ` [PATCH AUTOSEL 4.4 15/29] media: igorplugusb: receiver overflow should be reported Sasha Levin
2022-01-18 3:08 ` [PATCH AUTOSEL 4.4 16/29] media: saa7146: hexium_gemini: Fix a NULL pointer dereference in hexium_attach() Sasha Levin
4 siblings, 1 reply; 6+ messages in thread
From: Sasha Levin @ 2022-01-18 3:08 UTC (permalink / raw)
To: linux-kernel, stable
Cc: Mauro Carvalho Chehab, rkardell, Sasha Levin, mchehab,
linux-media
From: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
[ Upstream commit a2ab06d7c4d6bfd0b545a768247a70463e977e27 ]
Using stack-allocated pointers for USB message data don't work.
This driver is almost OK with that, except for the I2C read
logic.
Fix it by using a temporary read buffer, just like on all other
calls to m920x_read().
Link: https://lore.kernel.org/all/ccc99e48-de4f-045e-0fe4-61e3118e3f74@mida.se/
Reported-by: rkardell@mida.se
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/media/usb/dvb-usb/m920x.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/drivers/media/usb/dvb-usb/m920x.c b/drivers/media/usb/dvb-usb/m920x.c
index eafc5c82467f4..5b806779e2106 100644
--- a/drivers/media/usb/dvb-usb/m920x.c
+++ b/drivers/media/usb/dvb-usb/m920x.c
@@ -284,6 +284,13 @@ static int m920x_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[], int nu
/* Should check for ack here, if we knew how. */
}
if (msg[i].flags & I2C_M_RD) {
+ char *read = kmalloc(1, GFP_KERNEL);
+ if (!read) {
+ ret = -ENOMEM;
+ kfree(read);
+ goto unlock;
+ }
+
for (j = 0; j < msg[i].len; j++) {
/* Last byte of transaction?
* Send STOP, otherwise send ACK. */
@@ -291,9 +298,12 @@ static int m920x_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[], int nu
if ((ret = m920x_read(d->udev, M9206_I2C, 0x0,
0x20 | stop,
- &msg[i].buf[j], 1)) != 0)
+ read, 1)) != 0)
goto unlock;
+ msg[i].buf[j] = read[0];
}
+
+ kfree(read);
} else {
for (j = 0; j < msg[i].len; j++) {
/* Last byte of transaction? Then send STOP. */
--
2.34.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH AUTOSEL 4.4 15/29] media: igorplugusb: receiver overflow should be reported
[not found] <20220118030822.1955469-1-sashal@kernel.org>
` (2 preceding siblings ...)
2022-01-18 3:08 ` [PATCH AUTOSEL 4.4 11/29] media: m920x: don't use stack on USB reads Sasha Levin
@ 2022-01-18 3:08 ` Sasha Levin
2022-01-18 3:08 ` [PATCH AUTOSEL 4.4 16/29] media: saa7146: hexium_gemini: Fix a NULL pointer dereference in hexium_attach() Sasha Levin
4 siblings, 0 replies; 6+ messages in thread
From: Sasha Levin @ 2022-01-18 3:08 UTC (permalink / raw)
To: linux-kernel, stable
Cc: Sean Young, Mauro Carvalho Chehab, Sasha Levin, mchehab,
linux-media
From: Sean Young <sean@mess.org>
[ Upstream commit 8fede658e7ddb605bbd68ed38067ddb0af033db4 ]
Without this, some IR will be missing mid-stream and we might decode
something which never really occurred.
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/media/rc/igorplugusb.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/media/rc/igorplugusb.c b/drivers/media/rc/igorplugusb.c
index b36e51576f8e4..645ea00c472ab 100644
--- a/drivers/media/rc/igorplugusb.c
+++ b/drivers/media/rc/igorplugusb.c
@@ -73,9 +73,11 @@ static void igorplugusb_irdata(struct igorplugusb *ir, unsigned len)
if (start >= len) {
dev_err(ir->dev, "receive overflow invalid: %u", overflow);
} else {
- if (overflow > 0)
+ if (overflow > 0) {
dev_warn(ir->dev, "receive overflow, at least %u lost",
overflow);
+ ir_raw_event_reset(ir->rc);
+ }
do {
rawir.duration = ir->buf_in[i] * 85333;
--
2.34.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH AUTOSEL 4.4 16/29] media: saa7146: hexium_gemini: Fix a NULL pointer dereference in hexium_attach()
[not found] <20220118030822.1955469-1-sashal@kernel.org>
` (3 preceding siblings ...)
2022-01-18 3:08 ` [PATCH AUTOSEL 4.4 15/29] media: igorplugusb: receiver overflow should be reported Sasha Levin
@ 2022-01-18 3:08 ` Sasha Levin
4 siblings, 0 replies; 6+ messages in thread
From: Sasha Levin @ 2022-01-18 3:08 UTC (permalink / raw)
To: linux-kernel, stable
Cc: Zhou Qingyang, Mauro Carvalho Chehab, Sasha Levin, hverkuil,
mchehab, linux-media
From: Zhou Qingyang <zhou1615@umn.edu>
[ Upstream commit 3af86b046933ba513d08399dba0d4d8b50d607d0 ]
In hexium_attach(dev, info), saa7146_vv_init() is called to allocate
a new memory for dev->vv_data. saa7146_vv_release() will be called on
failure of saa7146_register_device(). There is a dereference of
dev->vv_data in saa7146_vv_release(), which could lead to a NULL
pointer dereference on failure of saa7146_vv_init().
Fix this bug by adding a check of saa7146_vv_init().
This bug was found by a static analyzer. The analysis employs
differential checking to identify inconsistent security operations
(e.g., checks or kfrees) between two code paths and confirms that the
inconsistent operations are not recovered in the current function or
the callers, so they constitute bugs.
Note that, as a bug found by static analysis, it can be a false
positive or hard to trigger. Multiple researchers have cross-reviewed
the bug.
Builds with CONFIG_VIDEO_HEXIUM_GEMINI=m show no new warnings,
and our static analyzer no longer warns about this code.
Link: https://lore.kernel.org/linux-media/20211203154030.111210-1-zhou1615@umn.edu
Signed-off-by: Zhou Qingyang <zhou1615@umn.edu>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/media/common/saa7146/saa7146_fops.c | 2 +-
drivers/media/pci/saa7146/hexium_gemini.c | 7 ++++++-
2 files changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/media/common/saa7146/saa7146_fops.c b/drivers/media/common/saa7146/saa7146_fops.c
index df1e8c975cd82..6d0a0b08853b4 100644
--- a/drivers/media/common/saa7146/saa7146_fops.c
+++ b/drivers/media/common/saa7146/saa7146_fops.c
@@ -524,7 +524,7 @@ int saa7146_vv_init(struct saa7146_dev* dev, struct saa7146_ext_vv *ext_vv)
ERR("out of memory. aborting.\n");
kfree(vv);
v4l2_ctrl_handler_free(hdl);
- return -1;
+ return -ENOMEM;
}
saa7146_video_uops.init(dev,vv);
diff --git a/drivers/media/pci/saa7146/hexium_gemini.c b/drivers/media/pci/saa7146/hexium_gemini.c
index 343cd75fcd8d1..f09f311a316f5 100644
--- a/drivers/media/pci/saa7146/hexium_gemini.c
+++ b/drivers/media/pci/saa7146/hexium_gemini.c
@@ -296,7 +296,12 @@ static int hexium_attach(struct saa7146_dev *dev, struct saa7146_pci_extension_d
hexium_set_input(hexium, 0);
hexium->cur_input = 0;
- saa7146_vv_init(dev, &vv_data);
+ ret = saa7146_vv_init(dev, &vv_data);
+ if (ret) {
+ i2c_del_adapter(&hexium->i2c_adapter);
+ kfree(hexium);
+ return ret;
+ }
vv_data.vid_ops.vidioc_enum_input = vidioc_enum_input;
vv_data.vid_ops.vidioc_g_input = vidioc_g_input;
--
2.34.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH AUTOSEL 4.4 11/29] media: m920x: don't use stack on USB reads
2022-01-18 3:08 ` [PATCH AUTOSEL 4.4 11/29] media: m920x: don't use stack on USB reads Sasha Levin
@ 2022-01-20 10:26 ` Pavel Machek
0 siblings, 0 replies; 6+ messages in thread
From: Pavel Machek @ 2022-01-20 10:26 UTC (permalink / raw)
To: Sasha Levin
Cc: linux-kernel, stable, Mauro Carvalho Chehab, rkardell, mchehab,
linux-media
[-- Attachment #1: Type: text/plain, Size: 2904 bytes --]
Hi!
> From: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
>
> [ Upstream commit a2ab06d7c4d6bfd0b545a768247a70463e977e27 ]
>
> Using stack-allocated pointers for USB message data don't work.
> This driver is almost OK with that, except for the I2C read
> logic.
>
> Fix it by using a temporary read buffer, just like on all other
> calls to m920x_read().
This introduces memory leak... and I don't believe it really fixes the
problem.
> index eafc5c82467f4..5b806779e2106 100644
> --- a/drivers/media/usb/dvb-usb/m920x.c
> +++ b/drivers/media/usb/dvb-usb/m920x.c
> @@ -284,6 +284,13 @@ static int m920x_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[], int nu
> /* Should check for ack here, if we knew how. */
> }
> if (msg[i].flags & I2C_M_RD) {
> + char *read = kmalloc(1, GFP_KERNEL);
> + if (!read) {
> + ret = -ENOMEM;
> + kfree(read);
> + goto unlock;
> + }
kfree(NULL);
> for (j = 0; j < msg[i].len; j++) {
> /* Last byte of transaction?
> * Send STOP, otherwise send ACK. */
> @@ -291,9 +298,12 @@ static int m920x_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[], int nu
>
> if ((ret = m920x_read(d->udev, M9206_I2C, 0x0,
> 0x20 | stop,
> - &msg[i].buf[j], 1)) != 0)
> + read, 1)) != 0)
> goto unlock;
Memory leak of read.
> + msg[i].buf[j] = read[0];
> }
> +
> + kfree(read);
> } else {
> for (j = 0; j < msg[i].len; j++) {
> /* Last byte of transaction? Then send STOP. */
But more importantly, do we have exact copy of the read problem just
below, during write?
Best regards,
Pavel
diff --git a/drivers/media/usb/dvb-usb/m920x.c b/drivers/media/usb/dvb-usb/m920x.c
index 691e05833db1..e5ee54324a28 100644
--- a/drivers/media/usb/dvb-usb/m920x.c
+++ b/drivers/media/usb/dvb-usb/m920x.c
@@ -250,7 +250,7 @@ static int m920x_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[], int nu
{
struct dvb_usb_device *d = i2c_get_adapdata(adap);
int i, j;
- int ret = 0;
+ int ret;
if (mutex_lock_interruptible(&d->i2c_mutex) < 0)
return -EAGAIN;
@@ -277,7 +277,6 @@ static int m920x_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[], int nu
char *read = kmalloc(1, GFP_KERNEL);
if (!read) {
ret = -ENOMEM;
- kfree(read);
goto unlock;
}
@@ -288,8 +287,10 @@ static int m920x_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msg[], int nu
if ((ret = m920x_read(d->udev, M9206_I2C, 0x0,
0x20 | stop,
- read, 1)) != 0)
+ read, 1)) != 0) {
+ kfree(read);
goto unlock;
+ }
msg[i].buf[j] = read[0];
}
--
DENX Software Engineering GmbH, Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 181 bytes --]
^ permalink raw reply related [flat|nested] 6+ messages in thread
end of thread, other threads:[~2022-01-20 10:26 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
[not found] <20220118030822.1955469-1-sashal@kernel.org>
2022-01-18 3:07 ` [PATCH AUTOSEL 4.4 05/29] media: b2c2: Add missing check in flexcop_pci_isr: Sasha Levin
2022-01-18 3:08 ` [PATCH AUTOSEL 4.4 10/29] media: saa7146: hexium_orion: Fix a NULL pointer dereference in hexium_attach() Sasha Levin
2022-01-18 3:08 ` [PATCH AUTOSEL 4.4 11/29] media: m920x: don't use stack on USB reads Sasha Levin
2022-01-20 10:26 ` Pavel Machek
2022-01-18 3:08 ` [PATCH AUTOSEL 4.4 15/29] media: igorplugusb: receiver overflow should be reported Sasha Levin
2022-01-18 3:08 ` [PATCH AUTOSEL 4.4 16/29] media: saa7146: hexium_gemini: Fix a NULL pointer dereference in hexium_attach() Sasha Levin
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