[syzbot] [dri?] general protection fault in drm_object_attach_property

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3d6d817622b0 Merge tag 'scsi-fixes' of git://git.kernel.or..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15432c79580000
kernel config: https://syzkaller.appspot.com/x/.config?x=8a233ed2ce9a8096
dashboard link: https://syzkaller.appspot.com/bug?extid=1944765c3659f63d3777
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
userspace arch: i386
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10b78ac6580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14735149580000

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-3d6d8176.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/b5f85cb20f42/vmlinux-3d6d8176.xz
kernel image: https://storage.googleapis.com/syzbot-assets/8ee2de80a3a1/bzImage-3d6d8176.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+194476...@syzkaller.appspotmail.com

usb 5-1: config 1 interface 0 altsetting 0 bulk endpoint 0x1 has invalid maxpacket 0
usb 5-1: config 1 interface 0 altsetting 0 has 1 endpoint descriptor, different from the interface descriptor's value: 2
usb 5-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
Oops: general protection fault, probably for non-canonical address 0xdffffc000000000c: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000060-0x0000000000000067]
CPU: 2 UID: 0 PID: 852 Comm: kworker/2:2 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Workqueue: usb_hub_wq hub_event
RIP: 0010:drm_object_attach_property+0x85/0x3b0 drivers/gpu/drm/drm_mode_object.c:240
Code: 0f b6 04 02 84 c0 74 08 3c 03 0f 8e 93 02 00 00 49 8d 7c 24 60 49 63 5d 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 a2 02 00 00 48 8d 7d 04 4d 8b 74 24 60 48 b8 00
RSP: 0000:ffffc900038f6e60 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000007 RCX: ffffffff86574465
RDX: 000000000000000c RSI: ffffffff85c3beb2 RDI: 0000000000000060
RBP: ffff888012bfe040 R08: 0000000000000007 R09: fffffffffffff000
R10: ffff888012bfece4 R11: 0000000000000000 R12: 0000000000000000
R13: ffff888012bfe228 R14: ffff888012bfece4 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888096df3000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000561c6bdd7168 CR3: 000000005d115000 CR4: 0000000000352ef0
Call Trace:
<TASK>
gud_connector_add_properties drivers/gpu/drm/gud/gud_connector.c:572 [inline]
gud_connector_create drivers/gpu/drm/gud/gud_connector.c:680 [inline]
gud_get_connectors+0x86e/0x1700 drivers/gpu/drm/gud/gud_connector.c:717
gud_probe+0x17aa/0x1c20 drivers/gpu/drm/gud/gud_drv.c:635
usb_probe_interface+0x303/0x8f0 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:628 [inline]
really_probe+0x241/0xa60 drivers/base/dd.c:706
__driver_probe_device+0x20e/0x450 drivers/base/dd.c:868
driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
__device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098
device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153
bus_probe_device+0x64/0x160 drivers/base/bus.c:620
device_add+0x121d/0x1970 drivers/base/core.c:3772
usb_set_configuration+0xd97/0x1c60 drivers/usb/core/message.c:2268
usb_generic_driver_probe+0xa1/0xe0 drivers/usb/core/generic.c:250
usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:291
call_driver_probe drivers/base/dd.c:628 [inline]
really_probe+0x241/0xa60 drivers/base/dd.c:706
__driver_probe_device+0x20e/0x450 drivers/base/dd.c:868
driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
__device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026
bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
__device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098
device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153
bus_probe_device+0x64/0x160 drivers/base/bus.c:620
device_add+0x121d/0x1970 drivers/base/core.c:3772
usb_new_device.part.0+0xcc2/0x1686 drivers/usb/core/hub.c:2703
usb_new_device include/linux/workqueue.h:714 [inline]
hub_port_connect drivers/usb/core/hub.c:5575 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5715 [inline]
port_event drivers/usb/core/hub.c:5879 [inline]
hub_event.cold+0x1e3/0xe90 drivers/usb/core/hub.c:5961
process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
process_scheduled_works kernel/workqueue.c:3405 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:drm_object_attach_property+0x85/0x3b0 drivers/gpu/drm/drm_mode_object.c:240
Code: 0f b6 04 02 84 c0 74 08 3c 03 0f 8e 93 02 00 00 49 8d 7c 24 60 49 63 5d 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 a2 02 00 00 48 8d 7d 04 4d 8b 74 24 60 48 b8 00
RSP: 0000:ffffc900038f6e60 EFLAGS: 00010206
RAX: dffffc0000000000 RBX: 0000000000000007 RCX: ffffffff86574465
RDX: 000000000000000c RSI: ffffffff85c3beb2 RDI: 0000000000000060
RBP: ffff888012bfe040 R08: 0000000000000007 R09: fffffffffffff000
R10: ffff888012bfece4 R11: 0000000000000000 R12: 0000000000000000
R13: ffff888012bfe228 R14: ffff888012bfece4 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888096df3000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000561c6bdd7168 CR3: 000000005d115000 CR4: 0000000000352ef0
----------------
Code disassembly (best guess):
0: 0f b6 04 02 movzbl (%rdx,%rax,1),%eax
4: 84 c0 test %al,%al
6: 74 08 je 0x10
8: 3c 03 cmp $0x3,%al
a: 0f 8e 93 02 00 00 jle 0x2a3
10: 49 8d 7c 24 60 lea 0x60(%r12),%rdi
15: 49 63 5d 00 movslq 0x0(%r13),%rbx
19: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
20: fc ff df
23: 48 89 fa mov %rdi,%rdx
26: 48 c1 ea 03 shr $0x3,%rdx
* 2a: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction
2e: 0f 85 a2 02 00 00 jne 0x2d6
34: 48 8d 7d 04 lea 0x4(%rbp),%rdi
38: 4d 8b 74 24 60 mov 0x60(%r12),%r14
3d: 48 rex.W
3e: b8 .byte 0xb8


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

[Edward Adam Davis]

#syz test

diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index 11646453aaac..ecbbc967f51f 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -2175,8 +2175,12 @@ int drm_mode_create_tv_properties_legacy(struct drm_device *dev,
struct drm_property *tv_subconnector;
unsigned int i;

- if (dev->mode_config.tv_select_subconnector_property)
+ if (dev->mode_config.tv_select_subconnector_property) {
+ if (num_modes && !dev->mode_config.legacy_tv_mode_property)
+ goto other;
+
return 0;
+ }

/*
* Basic connector properties
@@ -2199,6 +2203,7 @@ int drm_mode_create_tv_properties_legacy(struct drm_device *dev,
goto nomem;
dev->mode_config.tv_subconnector_property = tv_subconnector;

+other:
/*
* Other, TV specific properties: margins & TV modes.
*/

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+194476...@syzkaller.appspotmail.com
Tested-by: syzbot+194476...@syzkaller.appspotmail.com

Tested on:

commit: 8d3ae592 Linux 7.2
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13a7d6c6580000

kernel config: https://syzkaller.appspot.com/x/.config?x=8a233ed2ce9a8096
dashboard link: https://syzkaller.appspot.com/bug?extid=1944765c3659f63d3777
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
userspace arch: i386

patch: https://syzkaller.appspot.com/x/patch.diff?x=10e92679580000

Note: testing is done by a robot and is best-effort only.

[Edward Adam Davis]

When adding gud properties for drm connector within the function
gud_connector_add_properties(), if the TV modes property is not added
first, drm_mode_create_tv_properties_legacy() would fail to add the TV
modes property because the tv_select_subconnector_property has already
been added.

This causes gud_connector_property_lookup() to fail when looking for
the TV modes property (returning NULL), which subsequently triggers
issue [1] when a NULL property is passed to drm_object_attach_property().

The fix ensures that within drm_mode_create_tv_properties_legacy(), the
TV modes property is correctly added regardless of whether the subconnector
property exists.

[1]

Oops: general protection fault, probably for non-canonical address 0xdffffc000000000c: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000060-0x0000000000000067]

RIP: 0010:drm_object_attach_property+0x85/0x3b0 drivers/gpu/drm/drm_mode_object.c:240

Call Trace:

gud_connector_add_properties drivers/gpu/drm/gud/gud_connector.c:572 [inline]
gud_connector_create drivers/gpu/drm/gud/gud_connector.c:680 [inline]
gud_get_connectors+0x86e/0x1700 drivers/gpu/drm/gud/gud_connector.c:717
gud_probe+0x17aa/0x1c20 drivers/gpu/drm/gud/gud_drv.c:635

Fixes: f453ba046074 ("DRM: add mode setting support")
Reported-by: syzbot+194476...@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=1944765c3659f63d3777
Tested-by: syzbot+194476...@syzkaller.appspotmail.com
Signed-off-by: Edward Adam Davis <ead...@qq.com>
---
drivers/gpu/drm/drm_connector.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

--
2.43.0

[Edward Adam Davis]

#syz test

diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index 11646453aaac..12f4c5fcec92 100644

--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -2175,8 +2175,12 @@ int drm_mode_create_tv_properties_legacy(struct drm_device *dev,
struct drm_property *tv_subconnector;
unsigned int i;

- if (dev->mode_config.tv_select_subconnector_property)
+ if (dev->mode_config.tv_select_subconnector_property) {
+ if (num_modes && !dev->mode_config.legacy_tv_mode_property)

+ goto tv_mode;

+
return 0;
+ }

/*
* Basic connector properties

@@ -2205,18 +2209,6 @@ int drm_mode_create_tv_properties_legacy(struct drm_device *dev,
if (drm_mode_create_tv_margin_properties(dev))
goto nomem;

- if (num_modes) {
- dev->mode_config.legacy_tv_mode_property =
- drm_property_create(dev, DRM_MODE_PROP_ENUM,
- "mode", num_modes);
- if (!dev->mode_config.legacy_tv_mode_property)
- goto nomem;
-
- for (i = 0; i < num_modes; i++)
- drm_property_add_enum(dev->mode_config.legacy_tv_mode_property,
- i, modes[i]);
- }
-
dev->mode_config.tv_brightness_property =
drm_property_create_range(dev, 0, "brightness", 0, 100);
if (!dev->mode_config.tv_brightness_property)
@@ -2247,6 +2239,19 @@ int drm_mode_create_tv_properties_legacy(struct drm_device *dev,
if (!dev->mode_config.tv_hue_property)
goto nomem;

+tv_mode:
+ if (num_modes) {
+ dev->mode_config.legacy_tv_mode_property =
+ drm_property_create(dev, DRM_MODE_PROP_ENUM,
+ "mode", num_modes);
+ if (!dev->mode_config.legacy_tv_mode_property)
+ goto nomem;
+
+ for (i = 0; i < num_modes; i++)
+ drm_property_add_enum(dev->mode_config.legacy_tv_mode_property,
+ i, modes[i]);
+ }
+
return 0;
nomem:
return -ENOMEM;

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+194476...@syzkaller.appspotmail.com
Tested-by: syzbot+194476...@syzkaller.appspotmail.com

Tested on:

commit: 8d3ae592 Linux 7.2
git tree: upstream

console output: https://syzkaller.appspot.com/x/log.txt?x=147f2679580000

kernel config: https://syzkaller.appspot.com/x/.config?x=8a233ed2ce9a8096
dashboard link: https://syzkaller.appspot.com/bug?extid=1944765c3659f63d3777
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
userspace arch: i386

patch: https://syzkaller.appspot.com/x/patch.diff?x=12af2679580000

[Edward Adam Davis]

#syz test

diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c

index 11646453aaac..800fcc44e3f4 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -2175,29 +2175,30 @@ int drm_mode_create_tv_properties_legacy(struct drm_device *dev,

struct drm_property *tv_subconnector;
unsigned int i;

- if (dev->mode_config.tv_select_subconnector_property)

- return 0;
-
- /*
- * Basic connector properties
- */
- tv_selector = drm_property_create_enum(dev, 0,
- "select subconnector",
- drm_tv_select_enum_list,
- ARRAY_SIZE(drm_tv_select_enum_list));
- if (!tv_selector)
- goto nomem;
+ if (!dev->mode_config.tv_select_subconnector_property) {
+ /*
+ * Basic connector properties
+ */
+ tv_selector = drm_property_create_enum(dev, 0,
+ "select subconnector",
+ drm_tv_select_enum_list,
+ ARRAY_SIZE(drm_tv_select_enum_list));
+ if (!tv_selector)
+ goto nomem;

- dev->mode_config.tv_select_subconnector_property = tv_selector;
+ dev->mode_config.tv_select_subconnector_property = tv_selector;
+ }

- tv_subconnector =
- drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
- "subconnector",
- drm_tv_subconnector_enum_list,
- ARRAY_SIZE(drm_tv_subconnector_enum_list));
- if (!tv_subconnector)
- goto nomem;
- dev->mode_config.tv_subconnector_property = tv_subconnector;
+ if (!dev->mode_config.tv_subconnector_property) {
+ tv_subconnector =
+ drm_property_create_enum(dev, DRM_MODE_PROP_IMMUTABLE,
+ "subconnector",
+ drm_tv_subconnector_enum_list,
+ ARRAY_SIZE(drm_tv_subconnector_enum_list));
+ if (!tv_subconnector)
+ goto nomem;
+ dev->mode_config.tv_subconnector_property = tv_subconnector;
+ }

/*
* Other, TV specific properties: margins & TV modes.

@@ -2205,7 +2206,7 @@ int drm_mode_create_tv_properties_legacy(struct drm_device *dev,

if (drm_mode_create_tv_margin_properties(dev))
goto nomem;

- if (num_modes) {

+ if (num_modes && !dev->mode_config.legacy_tv_mode_property) {
dev->mode_config.legacy_tv_mode_property =
drm_property_create(dev, DRM_MODE_PROP_ENUM,
"mode", num_modes);
@@ -2217,35 +2218,48 @@ int drm_mode_create_tv_properties_legacy(struct drm_device *dev,
i, modes[i]);
}

- dev->mode_config.tv_brightness_property =
- drm_property_create_range(dev, 0, "brightness", 0, 100);
- if (!dev->mode_config.tv_brightness_property)
- goto nomem;
+ if (!dev->mode_config.tv_brightness_property) {
+ dev->mode_config.tv_brightness_property =
+ drm_property_create_range(dev, 0, "brightness", 0, 100);
+ if (!dev->mode_config.tv_brightness_property)
+ goto nomem;
+ }

- dev->mode_config.tv_contrast_property =
- drm_property_create_range(dev, 0, "contrast", 0, 100);
- if (!dev->mode_config.tv_contrast_property)
- goto nomem;
+ if (!dev->mode_config.tv_contrast_property) {
+ dev->mode_config.tv_contrast_property =
+ drm_property_create_range(dev, 0, "contrast", 0, 100);
+ if (!dev->mode_config.tv_contrast_property)
+ goto nomem;
+ }

- dev->mode_config.tv_flicker_reduction_property =
- drm_property_create_range(dev, 0, "flicker reduction", 0, 100);
- if (!dev->mode_config.tv_flicker_reduction_property)
- goto nomem;
+ if (!dev->mode_config.tv_flicker_reduction_property) {
+ dev->mode_config.tv_flicker_reduction_property =
+ drm_property_create_range(dev, 0, "flicker reduction",
+ 0, 100);
+ if (!dev->mode_config.tv_flicker_reduction_property)
+ goto nomem;
+ }

- dev->mode_config.tv_overscan_property =
- drm_property_create_range(dev, 0, "overscan", 0, 100);
- if (!dev->mode_config.tv_overscan_property)
- goto nomem;
+ if (!dev->mode_config.tv_overscan_property) {
+ dev->mode_config.tv_overscan_property =
+ drm_property_create_range(dev, 0, "overscan", 0, 100);
+ if (!dev->mode_config.tv_overscan_property)
+ goto nomem;
+ }

- dev->mode_config.tv_saturation_property =
- drm_property_create_range(dev, 0, "saturation", 0, 100);
- if (!dev->mode_config.tv_saturation_property)
- goto nomem;
+ if (!dev->mode_config.tv_saturation_property) {
+ dev->mode_config.tv_saturation_property =
+ drm_property_create_range(dev, 0, "saturation", 0, 100);
+ if (!dev->mode_config.tv_saturation_property)
+ goto nomem;
+ }

- dev->mode_config.tv_hue_property =
- drm_property_create_range(dev, 0, "hue", 0, 100);
- if (!dev->mode_config.tv_hue_property)
- goto nomem;
+ if (!dev->mode_config.tv_hue_property) {
+ dev->mode_config.tv_hue_property =
+ drm_property_create_range(dev, 0, "hue", 0, 100);
+ if (!dev->mode_config.tv_hue_property)
+ goto nomem;
+ }

return 0;
nomem:

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+194476...@syzkaller.appspotmail.com
Tested-by: syzbot+194476...@syzkaller.appspotmail.com

Tested on:

commit: 8d3ae592 Linux 7.2
git tree: upstream

console output: https://syzkaller.appspot.com/x/log.txt?x=12a93a79580000

kernel config: https://syzkaller.appspot.com/x/.config?x=8a233ed2ce9a8096
dashboard link: https://syzkaller.appspot.com/bug?extid=1944765c3659f63d3777
compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
userspace arch: i386

patch: https://syzkaller.appspot.com/x/patch.diff?x=14313a79580000

[Ruben Wauters]

Acked-by: Ruben Wauters <rube...@aol.com>