* [PATCH] media:usb:zr364xx:Fix KASAN:null-ptr-deref Read in zr364xx_vidioc_querycap
@ 2019-05-21 18:15 Vandana BN
2019-05-22 6:52 ` Hans Verkuil
2019-05-22 8:34 ` [PATCH v2] " Vandana BN
0 siblings, 2 replies; 4+ messages in thread
From: Vandana BN @ 2019-05-21 18:15 UTC (permalink / raw)
To: hverkuil, royale, mchehab, linux-usb, linux-media, linux-kernel
Cc: skhan, gregkh, linux-kernel-mentees, Vandana BN
SyzKaller hit the null pointer deref while reading from uninitialized
udev->product in zr364xx_vidioc_querycap().
==================================================================
BUG: KASAN: null-ptr-deref in read_word_at_a_time+0xe/0x20
include/linux/compiler.h:274
Read of size 1 at addr 0000000000000000 by task v4l_id/5287
CPU: 1 PID: 5287 Comm: v4l_id Not tainted 5.1.0-rc3-319004-g43151d6 #6
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0xe8/0x16e lib/dump_stack.c:113
kasan_report.cold+0x5/0x3c mm/kasan/report.c:321
read_word_at_a_time+0xe/0x20 include/linux/compiler.h:274
strscpy+0x8a/0x280 lib/string.c:207
zr364xx_vidioc_querycap+0xb5/0x210 drivers/media/usb/zr364xx/zr364xx.c:706
v4l_querycap+0x12b/0x340 drivers/media/v4l2-core/v4l2-ioctl.c:1062
__video_do_ioctl+0x5bb/0xb40 drivers/media/v4l2-core/v4l2-ioctl.c:2874
video_usercopy+0x44e/0xf00 drivers/media/v4l2-core/v4l2-ioctl.c:3056
v4l2_ioctl+0x14e/0x1a0 drivers/media/v4l2-core/v4l2-dev.c:364
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:509 [inline]
do_vfs_ioctl+0xced/0x12f0 fs/ioctl.c:696
ksys_ioctl+0xa0/0xc0 fs/ioctl.c:713
__do_sys_ioctl fs/ioctl.c:720 [inline]
__se_sys_ioctl fs/ioctl.c:718 [inline]
__x64_sys_ioctl+0x74/0xb0 fs/ioctl.c:718
do_syscall_64+0xcf/0x4f0 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f3b56d8b347
Code: 90 90 90 48 8b 05 f1 fa 2a 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff
ff c3 90 90 90 90 90 90 90 90 90 90 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff
ff 73 01 c3 48 8b 0d c1 fa 2a 00 31 d2 48 29 c2 64
RSP: 002b:00007ffe005d5d68 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f3b56d8b347
RDX: 00007ffe005d5d70 RSI: 0000000080685600 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000400884
R13: 00007ffe005d5ec0 R14: 0000000000000000 R15: 0000000000000000
==================================================================
For this device udev->product is not initialized and accessing it causes a NULL pointer deref.
The fix is to check for NULL before strscpy() and copy empty string, if
product is NULL
Reported-by: syzbot+66010012fd4c531a1a96@syzkaller.appspotmail.com
Signed-off-by: Vandana BN <bnvandana@gmail.com>
---
drivers/media/usb/zr364xx/zr364xx.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/drivers/media/usb/zr364xx/zr364xx.c b/drivers/media/usb/zr364xx/zr364xx.c
index 96fee8d5b865..401a1e55dbe1 100644
--- a/drivers/media/usb/zr364xx/zr364xx.c
+++ b/drivers/media/usb/zr364xx/zr364xx.c
@@ -703,7 +703,10 @@ static int zr364xx_vidioc_querycap(struct file *file, void *priv,
struct zr364xx_camera *cam = video_drvdata(file);
strscpy(cap->driver, DRIVER_DESC, sizeof(cap->driver));
- strscpy(cap->card, cam->udev->product, sizeof(cap->card));
+ if (cam->udev->product)
+ strscpy(cap->card, cam->udev->product, sizeof(cap->card));
+ else
+ strscpy(cap->card, "", sizeof(cap->card));
strscpy(cap->bus_info, dev_name(&cam->udev->dev),
sizeof(cap->bus_info));
cap->device_caps = V4L2_CAP_VIDEO_CAPTURE |
--
2.17.1
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH] media:usb:zr364xx:Fix KASAN:null-ptr-deref Read in zr364xx_vidioc_querycap
2019-05-21 18:15 [PATCH] media:usb:zr364xx:Fix KASAN:null-ptr-deref Read in zr364xx_vidioc_querycap Vandana BN
@ 2019-05-22 6:52 ` Hans Verkuil
2019-05-22 8:34 ` [PATCH v2] " Vandana BN
1 sibling, 0 replies; 4+ messages in thread
From: Hans Verkuil @ 2019-05-22 6:52 UTC (permalink / raw)
To: Vandana BN, royale, mchehab, linux-usb, linux-media, linux-kernel
Cc: skhan, gregkh, linux-kernel-mentees
On 5/21/19 8:15 PM, Vandana BN wrote:
> SyzKaller hit the null pointer deref while reading from uninitialized
> udev->product in zr364xx_vidioc_querycap().
> ==================================================================
> BUG: KASAN: null-ptr-deref in read_word_at_a_time+0xe/0x20
> include/linux/compiler.h:274
> Read of size 1 at addr 0000000000000000 by task v4l_id/5287
>
> CPU: 1 PID: 5287 Comm: v4l_id Not tainted 5.1.0-rc3-319004-g43151d6 #6
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
> Google 01/01/2011
> Call Trace:
> __dump_stack lib/dump_stack.c:77 [inline]
> dump_stack+0xe8/0x16e lib/dump_stack.c:113
> kasan_report.cold+0x5/0x3c mm/kasan/report.c:321
> read_word_at_a_time+0xe/0x20 include/linux/compiler.h:274
> strscpy+0x8a/0x280 lib/string.c:207
> zr364xx_vidioc_querycap+0xb5/0x210 drivers/media/usb/zr364xx/zr364xx.c:706
> v4l_querycap+0x12b/0x340 drivers/media/v4l2-core/v4l2-ioctl.c:1062
> __video_do_ioctl+0x5bb/0xb40 drivers/media/v4l2-core/v4l2-ioctl.c:2874
> video_usercopy+0x44e/0xf00 drivers/media/v4l2-core/v4l2-ioctl.c:3056
> v4l2_ioctl+0x14e/0x1a0 drivers/media/v4l2-core/v4l2-dev.c:364
> vfs_ioctl fs/ioctl.c:46 [inline]
> file_ioctl fs/ioctl.c:509 [inline]
> do_vfs_ioctl+0xced/0x12f0 fs/ioctl.c:696
> ksys_ioctl+0xa0/0xc0 fs/ioctl.c:713
> __do_sys_ioctl fs/ioctl.c:720 [inline]
> __se_sys_ioctl fs/ioctl.c:718 [inline]
> __x64_sys_ioctl+0x74/0xb0 fs/ioctl.c:718
> do_syscall_64+0xcf/0x4f0 arch/x86/entry/common.c:290
> entry_SYSCALL_64_after_hwframe+0x49/0xbe
> RIP: 0033:0x7f3b56d8b347
> Code: 90 90 90 48 8b 05 f1 fa 2a 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff
> ff c3 90 90 90 90 90 90 90 90 90 90 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff
> ff 73 01 c3 48 8b 0d c1 fa 2a 00 31 d2 48 29 c2 64
> RSP: 002b:00007ffe005d5d68 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
> RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f3b56d8b347
> RDX: 00007ffe005d5d70 RSI: 0000000080685600 RDI: 0000000000000003
> RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000400884
> R13: 00007ffe005d5ec0 R14: 0000000000000000 R15: 0000000000000000
> ==================================================================
>
> For this device udev->product is not initialized and accessing it causes a NULL pointer deref.
>
> The fix is to check for NULL before strscpy() and copy empty string, if
> product is NULL
>
> Reported-by: syzbot+66010012fd4c531a1a96@syzkaller.appspotmail.com
>
> Signed-off-by: Vandana BN <bnvandana@gmail.com>
> ---
> drivers/media/usb/zr364xx/zr364xx.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/media/usb/zr364xx/zr364xx.c b/drivers/media/usb/zr364xx/zr364xx.c
> index 96fee8d5b865..401a1e55dbe1 100644
> --- a/drivers/media/usb/zr364xx/zr364xx.c
> +++ b/drivers/media/usb/zr364xx/zr364xx.c
> @@ -703,7 +703,10 @@ static int zr364xx_vidioc_querycap(struct file *file, void *priv,
> struct zr364xx_camera *cam = video_drvdata(file);
>
> strscpy(cap->driver, DRIVER_DESC, sizeof(cap->driver));
> - strscpy(cap->card, cam->udev->product, sizeof(cap->card));
> + if (cam->udev->product)
> + strscpy(cap->card, cam->udev->product, sizeof(cap->card));
> + else
> + strscpy(cap->card, "", sizeof(cap->card));
You can drop the 'else' part since cap->card is already zeroed by the
V4L2 core framework. Looks good otherwise!
Regards,
Hans
> strscpy(cap->bus_info, dev_name(&cam->udev->dev),
> sizeof(cap->bus_info));
> cap->device_caps = V4L2_CAP_VIDEO_CAPTURE |
>
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH v2] media:usb:zr364xx:Fix KASAN:null-ptr-deref Read in zr364xx_vidioc_querycap
2019-05-21 18:15 [PATCH] media:usb:zr364xx:Fix KASAN:null-ptr-deref Read in zr364xx_vidioc_querycap Vandana BN
2019-05-22 6:52 ` Hans Verkuil
@ 2019-05-22 8:34 ` Vandana BN
2019-05-22 8:36 ` Hans Verkuil
1 sibling, 1 reply; 4+ messages in thread
From: Vandana BN @ 2019-05-22 8:34 UTC (permalink / raw)
To: hverkuil, royale, mchehab, linux-usb, linux-media, linux-kernel
Cc: skhan, gregkh, linux-kernel-mentees, Vandana BN
SyzKaller hit the null pointer deref while reading from uninitialized
udev->product in zr364xx_vidioc_querycap().
==================================================================
BUG: KASAN: null-ptr-deref in read_word_at_a_time+0xe/0x20
include/linux/compiler.h:274
Read of size 1 at addr 0000000000000000 by task v4l_id/5287
CPU: 1 PID: 5287 Comm: v4l_id Not tainted 5.1.0-rc3-319004-g43151d6 #6
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0xe8/0x16e lib/dump_stack.c:113
kasan_report.cold+0x5/0x3c mm/kasan/report.c:321
read_word_at_a_time+0xe/0x20 include/linux/compiler.h:274
strscpy+0x8a/0x280 lib/string.c:207
zr364xx_vidioc_querycap+0xb5/0x210 drivers/media/usb/zr364xx/zr364xx.c:706
v4l_querycap+0x12b/0x340 drivers/media/v4l2-core/v4l2-ioctl.c:1062
__video_do_ioctl+0x5bb/0xb40 drivers/media/v4l2-core/v4l2-ioctl.c:2874
video_usercopy+0x44e/0xf00 drivers/media/v4l2-core/v4l2-ioctl.c:3056
v4l2_ioctl+0x14e/0x1a0 drivers/media/v4l2-core/v4l2-dev.c:364
vfs_ioctl fs/ioctl.c:46 [inline]
file_ioctl fs/ioctl.c:509 [inline]
do_vfs_ioctl+0xced/0x12f0 fs/ioctl.c:696
ksys_ioctl+0xa0/0xc0 fs/ioctl.c:713
__do_sys_ioctl fs/ioctl.c:720 [inline]
__se_sys_ioctl fs/ioctl.c:718 [inline]
__x64_sys_ioctl+0x74/0xb0 fs/ioctl.c:718
do_syscall_64+0xcf/0x4f0 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f3b56d8b347
Code: 90 90 90 48 8b 05 f1 fa 2a 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff
ff c3 90 90 90 90 90 90 90 90 90 90 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff
ff 73 01 c3 48 8b 0d c1 fa 2a 00 31 d2 48 29 c2 64
RSP: 002b:00007ffe005d5d68 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f3b56d8b347
RDX: 00007ffe005d5d70 RSI: 0000000080685600 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000400884
R13: 00007ffe005d5ec0 R14: 0000000000000000 R15: 0000000000000000
==================================================================
For this device udev->product is not initialized and accessing it causes a NULL pointer deref.
The fix is to check for NULL before strscpy() and copy empty string, if
product is NULL
Reported-by: syzbot+66010012fd4c531a1a96@syzkaller.appspotmail.com
Signed-off-by: Vandana BN <bnvandana@gmail.com>
---
v2 - removed else part as cap->card is already zeroed.
drivers/media/usb/zr364xx/zr364xx.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/media/usb/zr364xx/zr364xx.c b/drivers/media/usb/zr364xx/zr364xx.c
index 96fee8d5b865..cd2bc9ed0cd9 100644
--- a/drivers/media/usb/zr364xx/zr364xx.c
+++ b/drivers/media/usb/zr364xx/zr364xx.c
@@ -703,7 +703,8 @@ static int zr364xx_vidioc_querycap(struct file *file, void *priv,
struct zr364xx_camera *cam = video_drvdata(file);
strscpy(cap->driver, DRIVER_DESC, sizeof(cap->driver));
- strscpy(cap->card, cam->udev->product, sizeof(cap->card));
+ if (cam->udev->product)
+ strscpy(cap->card, cam->udev->product, sizeof(cap->card));
strscpy(cap->bus_info, dev_name(&cam->udev->dev),
sizeof(cap->bus_info));
cap->device_caps = V4L2_CAP_VIDEO_CAPTURE |
--
2.17.1
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH v2] media:usb:zr364xx:Fix KASAN:null-ptr-deref Read in zr364xx_vidioc_querycap
2019-05-22 8:34 ` [PATCH v2] " Vandana BN
@ 2019-05-22 8:36 ` Hans Verkuil
0 siblings, 0 replies; 4+ messages in thread
From: Hans Verkuil @ 2019-05-22 8:36 UTC (permalink / raw)
To: Vandana BN, royale, mchehab, linux-usb, linux-media, linux-kernel
Cc: skhan, gregkh, linux-kernel-mentees
On 5/22/19 10:34 AM, Vandana BN wrote:
> SyzKaller hit the null pointer deref while reading from uninitialized
> udev->product in zr364xx_vidioc_querycap().
> ==================================================================
> BUG: KASAN: null-ptr-deref in read_word_at_a_time+0xe/0x20
> include/linux/compiler.h:274
> Read of size 1 at addr 0000000000000000 by task v4l_id/5287
>
> CPU: 1 PID: 5287 Comm: v4l_id Not tainted 5.1.0-rc3-319004-g43151d6 #6
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
> Google 01/01/2011
> Call Trace:
> __dump_stack lib/dump_stack.c:77 [inline]
> dump_stack+0xe8/0x16e lib/dump_stack.c:113
> kasan_report.cold+0x5/0x3c mm/kasan/report.c:321
> read_word_at_a_time+0xe/0x20 include/linux/compiler.h:274
> strscpy+0x8a/0x280 lib/string.c:207
> zr364xx_vidioc_querycap+0xb5/0x210 drivers/media/usb/zr364xx/zr364xx.c:706
> v4l_querycap+0x12b/0x340 drivers/media/v4l2-core/v4l2-ioctl.c:1062
> __video_do_ioctl+0x5bb/0xb40 drivers/media/v4l2-core/v4l2-ioctl.c:2874
> video_usercopy+0x44e/0xf00 drivers/media/v4l2-core/v4l2-ioctl.c:3056
> v4l2_ioctl+0x14e/0x1a0 drivers/media/v4l2-core/v4l2-dev.c:364
> vfs_ioctl fs/ioctl.c:46 [inline]
> file_ioctl fs/ioctl.c:509 [inline]
> do_vfs_ioctl+0xced/0x12f0 fs/ioctl.c:696
> ksys_ioctl+0xa0/0xc0 fs/ioctl.c:713
> __do_sys_ioctl fs/ioctl.c:720 [inline]
> __se_sys_ioctl fs/ioctl.c:718 [inline]
> __x64_sys_ioctl+0x74/0xb0 fs/ioctl.c:718
> do_syscall_64+0xcf/0x4f0 arch/x86/entry/common.c:290
> entry_SYSCALL_64_after_hwframe+0x49/0xbe
> RIP: 0033:0x7f3b56d8b347
> Code: 90 90 90 48 8b 05 f1 fa 2a 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff
> ff c3 90 90 90 90 90 90 90 90 90 90 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff
> ff 73 01 c3 48 8b 0d c1 fa 2a 00 31 d2 48 29 c2 64
> RSP: 002b:00007ffe005d5d68 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
> RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f3b56d8b347
> RDX: 00007ffe005d5d70 RSI: 0000000080685600 RDI: 0000000000000003
> RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000400884
> R13: 00007ffe005d5ec0 R14: 0000000000000000 R15: 0000000000000000
> ==================================================================
>
> For this device udev->product is not initialized and accessing it causes a NULL pointer deref.
>
> The fix is to check for NULL before strscpy() and copy empty string, if
> product is NULL
>
> Reported-by: syzbot+66010012fd4c531a1a96@syzkaller.appspotmail.com
>
> Signed-off-by: Vandana BN <bnvandana@gmail.com>
Looks good!
I'll take this patch for v5.3.
Regards,
Hans
> ---
> v2 - removed else part as cap->card is already zeroed.
>
> drivers/media/usb/zr364xx/zr364xx.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/media/usb/zr364xx/zr364xx.c b/drivers/media/usb/zr364xx/zr364xx.c
> index 96fee8d5b865..cd2bc9ed0cd9 100644
> --- a/drivers/media/usb/zr364xx/zr364xx.c
> +++ b/drivers/media/usb/zr364xx/zr364xx.c
> @@ -703,7 +703,8 @@ static int zr364xx_vidioc_querycap(struct file *file, void *priv,
> struct zr364xx_camera *cam = video_drvdata(file);
>
> strscpy(cap->driver, DRIVER_DESC, sizeof(cap->driver));
> - strscpy(cap->card, cam->udev->product, sizeof(cap->card));
> + if (cam->udev->product)
> + strscpy(cap->card, cam->udev->product, sizeof(cap->card));
> strscpy(cap->bus_info, dev_name(&cam->udev->dev),
> sizeof(cap->bus_info));
> cap->device_caps = V4L2_CAP_VIDEO_CAPTURE |
>
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2019-05-22 8:36 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-05-21 18:15 [PATCH] media:usb:zr364xx:Fix KASAN:null-ptr-deref Read in zr364xx_vidioc_querycap Vandana BN
2019-05-22 6:52 ` Hans Verkuil
2019-05-22 8:34 ` [PATCH v2] " Vandana BN
2019-05-22 8:36 ` Hans Verkuil
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