CVE-2024-26607 (GCVE-0-2024-26607)

Vulnerability from cvelistv5 – Published: 2024-02-29 11:47 – Updated: 2025-05-04 08:52
VLAI?
Title
drm/bridge: sii902x: Fix probing race issue
Summary
In the Linux kernel, the following vulnerability has been resolved: drm/bridge: sii902x: Fix probing race issue A null pointer dereference crash has been observed rarely on TI platforms using sii9022 bridge: [ 53.271356] sii902x_get_edid+0x34/0x70 [sii902x] [ 53.276066] sii902x_bridge_get_edid+0x14/0x20 [sii902x] [ 53.281381] drm_bridge_get_edid+0x20/0x34 [drm] [ 53.286305] drm_bridge_connector_get_modes+0x8c/0xcc [drm_kms_helper] [ 53.292955] drm_helper_probe_single_connector_modes+0x190/0x538 [drm_kms_helper] [ 53.300510] drm_client_modeset_probe+0x1f0/0xbd4 [drm] [ 53.305958] __drm_fb_helper_initial_config_and_unlock+0x50/0x510 [drm_kms_helper] [ 53.313611] drm_fb_helper_initial_config+0x48/0x58 [drm_kms_helper] [ 53.320039] drm_fbdev_dma_client_hotplug+0x84/0xd4 [drm_dma_helper] [ 53.326401] drm_client_register+0x5c/0xa0 [drm] [ 53.331216] drm_fbdev_dma_setup+0xc8/0x13c [drm_dma_helper] [ 53.336881] tidss_probe+0x128/0x264 [tidss] [ 53.341174] platform_probe+0x68/0xc4 [ 53.344841] really_probe+0x188/0x3c4 [ 53.348501] __driver_probe_device+0x7c/0x16c [ 53.352854] driver_probe_device+0x3c/0x10c [ 53.357033] __device_attach_driver+0xbc/0x158 [ 53.361472] bus_for_each_drv+0x88/0xe8 [ 53.365303] __device_attach+0xa0/0x1b4 [ 53.369135] device_initial_probe+0x14/0x20 [ 53.373314] bus_probe_device+0xb0/0xb4 [ 53.377145] deferred_probe_work_func+0xcc/0x124 [ 53.381757] process_one_work+0x1f0/0x518 [ 53.385770] worker_thread+0x1e8/0x3dc [ 53.389519] kthread+0x11c/0x120 [ 53.392750] ret_from_fork+0x10/0x20 The issue here is as follows: - tidss probes, but is deferred as sii902x is still missing. - sii902x starts probing and enters sii902x_init(). - sii902x calls drm_bridge_add(). Now the sii902x bridge is ready from DRM's perspective. - sii902x calls sii902x_audio_codec_init() and platform_device_register_data() - The registration of the audio platform device causes probing of the deferred devices. - tidss probes, which eventually causes sii902x_bridge_get_edid() to be called. - sii902x_bridge_get_edid() tries to use the i2c to read the edid. However, the sii902x driver has not set up the i2c part yet, leading to the crash. Fix this by moving the drm_bridge_add() to the end of the sii902x_init(), which is also at the very end of sii902x_probe().
Severity ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 21d808405fe49028036932dd969920f4fee4f481 , < e0f83c234ea7a3dec1f84e5d02caa1c51664a076 (git)
Affected: 21d808405fe49028036932dd969920f4fee4f481 , < 56f96cf6eb11a1c2d594367c3becbfb06a855ec1 (git)
Affected: 21d808405fe49028036932dd969920f4fee4f481 , < 2a4c6af7934a7b4c304542c38fee35e09cc1770c (git)
Affected: 21d808405fe49028036932dd969920f4fee4f481 , < 08ac6f132dd77e40f786d8af51140c96c6d739c9 (git)
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    Linux Linux Affected: 5.0
Unaffected: 0 , < 5.0 (semver)
Unaffected: 6.1.76 , ≤ 6.1.* (semver)
Unaffected: 6.6.15 , ≤ 6.6.* (semver)
Unaffected: 6.7.3 , ≤ 6.7.* (semver)
Unaffected: 6.8 , ≤ * (original_commit_for_fix)
Create a notification for this product.
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53.373314]  bus_probe_device+0xb0/0xb4\\n[   53.377145]  deferred_probe_work_func+0xcc/0x124\\n[   53.381757]  process_one_work+0x1f0/0x518\\n[   53.385770]  worker_thread+0x1e8/0x3dc\\n[   53.389519]  kthread+0x11c/0x120\\n[   53.392750]  ret_from_fork+0x10/0x20\\n\\nThe issue here is as follows:\\n\\n- tidss probes, but is deferred as sii902x is still missing.\\n- sii902x starts probing and enters sii902x_init().\\n- sii902x calls drm_bridge_add(). 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  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.