kernel/linux.git/drivers/gpu/drm/amd, branch v5.15.215

PCI: Fix restoring BARs on BAR resize rollback path

2026-07-24T13:51:58+00:00

[ Upstream commit 337b1b566db087347194e4543ddfdfa5645275cc ] BAR resize operation is implemented in the pci_resize_resource() and pbus_reassign_bridge_resources() functions. pci_resize_resource() can be called either from __resource_resize_store() from sysfs or directly by the driver for the Endpoint Device. The pci_resize_resource() requires that caller has released the device resources that share the bridge window with the BAR to be resized as otherwise the bridge window is pinned in place and cannot be changed. pbus_reassign_bridge_resources() rolls back resources if the resize operation fails, but rollback is performed only for the bridge windows. Because releasing the device resources are done by the caller of the BAR resize interface, these functions performing the BAR resize do not have access to the device resources as they were before the resize. pbus_reassign_bridge_resources() could try __pci_bridge_assign_resources() after rolling back the bridge windows as they were, however, it will not guarantee the resource are assigned due to differences in how FW and the kernel assign the resources (alignment of the start address and tail). To perform rollback robustly, the BAR resize interface has to be altered to also release the device resources that share the bridge window with the BAR to be resized. Also, remove restoring from the entries failed list as saved list should now contain both the bridge windows and device resources so the extra restore is duplicated work. Some drivers (currently only amdgpu) want to prevent releasing some resources. Add exclude_bars param to pci_resize_resource() and make amdgpu pass its register BAR (BAR 2 or 5), which should never be released during resize operation. Normally 64-bit prefetchable resources do not share a bridge window with the 32-bit only register BAR, but there are various fallbacks in the resource assignment logic which may make the resources share the bridge window in rare cases. This change (together with the driver side changes) is to counter the resource releases that had to be done to prevent resource tree corruption in the ("PCI: Release assigned resource before restoring them") change. As such, it likely restores functionality in cases where device resources were released to avoid resource tree conflicts which appeared to be "working" when such conflicts were not correctly detected by the kernel. Reported-by: Simon Richter Link: https://lore.kernel.org/linux-pci/f9a8c975-f5d3-4dd2-988e-4371a1433a60@hogyros.de/ Reported-by: Alex Bennée Link: https://lore.kernel.org/linux-pci/874irqop6b.fsf@draig.linaro.org/ Signed-off-by: Ilpo Järvinen [bhelgaas: squash amdgpu BAR selection from https: //lore.kernel.org/r/20251114103053.13778-1-ilpo.jarvinen@linux.intel.com] Signed-off-by: Bjorn Helgaas Tested-by: Alex Bennée # AVA, AMD GPU Reviewed-by: Christian König Link: https://patch.msgid.link/20251113162628.5946-7-ilpo.jarvinen@linux.intel.com Stable-dep-of: ee7471fe968d ("PCI: Skip Resizable BAR restore on read error") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

drm/amd/display: Add missing kdoc for ALLM parameters

2026-07-24T13:51:37+00:00

[ Upstream commit d4c6ec729fb7a8bf8a27b19bd70a1b945ad93dac ] Add descriptions for the missing parameters for ALLMEnabled and ALLMValue to keep the function documentation synchronized with the function prototype mod_build_hf_vsif_infopacket(). Fixes the below with gcc W=1: ../display/modules/info_packet/info_packet.c:507 function parameter 'ALLMEnabled' not described in 'mod_build_hf_vsif_infopacket' ../display/modules/info_packet/info_packet.c:507 function parameter 'ALLMValue' not described in 'mod_build_hf_vsif_infopacket' Fixes: 3c2381b92cba ("drm/amd/display: add support for VSIP info packet") Cc: Roman Li Cc: Alex Hung Cc: Tom Chung Cc: Aurabindo Pillai Cc: Wayne Lin Cc: Nicholas Kazlauskas Cc: Bhawanpreet Lakha Signed-off-by: Srinivasan Shanmugam Reviewed-by: Alex Hung Signed-off-by: Alex Deucher Signed-off-by: Sasha Levin

drm/amd/display: Bound VBIOS record-chain walk loops

2026-07-04T11:39:36+00:00

[ Upstream commit ff287df16a1a58aca78b08d1f3ee09fc44da0351 ] [Why & How] All record-chain walk loops in bios_parser.c and bios_parser2.c use for(;;) and only terminate on a 0xFF record_type sentinel or zero record_size. A malformed VBIOS image missing the terminator record causes unbounded iteration at probe time, potentially hundreds of thousands of iterations with record_size=1. In the final iterations near the BIOS image boundary, struct casts beyond the 2-byte header validated by GET_IMAGE can also read out of bounds. Cap all 14 record-chain walk loops to BIOS_MAX_NUM_RECORD (256) iterations. The atombios.h defines up to 22 distinct record types and atomfirmware.h has 13. Assuming an average of less than 10 records per type (which is reasonable since most are connector- based) 256 is a generous upper bound. Fixes: 4562236b3bc0 ("drm/amd/dc: Add dc display driver (v2)") Assisted-by: Copilot:claude-opus-4.6 Mythos Reviewed-by: Alex Hung Signed-off-by: Harry Wentland Signed-off-by: Ray Wu Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher (cherry picked from commit 95700a3d660287ed657d6892f7be9ffc0e294a93) Cc: stable@vger.kernel.org Signed-off-by: Sasha Levin

drm/amd/display: Use krealloc_array() in dal_vector_reserve()

2026-06-19T11:33:39+00:00

commit da48bc4461b8a5ebfb9264c9b191a701d8e99009 upstream. [Why & How] dal_vector_reserve() computes the allocation size as "capacity * vector->struct_size" using uint32_t arithmetic, which can silently wrap to a small value on overflow. This would cause krealloc to return a smaller buffer than expected, leading to heap overflows on subsequent vector appends. Replace krealloc() with krealloc_array() which performs an internal overflow check and returns NULL on wrap, preventing the issue. Fixes: 2004f45ef83f ("drm/amd/display: Use kernel alloc/free") Assisted-by: Copilot:claude-opus-4.6 Reviewed-by: Alex Hung Signed-off-by: Harry Wentland Signed-off-by: Ray Wu Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher (cherry picked from commit 37668568641ccc4cc1dbca4923d0a16609dd5707) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

drm/amd/display: Fix NULL deref and buffer over-read in SDP debugfs

2026-06-19T11:33:39+00:00

commit adf67034b1f61f7119295208085bfd43f85f56af upstream. [Why & How] dp_sdp_message_debugfs_write() dereferences connector->base.state->crtc without checking for NULL. A connector can be connected but not bound to any CRTC (e.g. after hot-plug before the next atomic commit), causing a kernel crash when writing to the sdp_message debugfs node. The function also ignores the user-provided size argument and always passes 36 bytes to copy_from_user(), reading past the user buffer when size < 36. Fix both issues by: - Returning -ENODEV when connector->base.state or state->crtc is NULL - Clamping write_size to min(size, sizeof(data)) Fixes: c7ba3653e977 ("drm/amd/display: Generic SDP message access in amdgpu") Assisted-by: Copilot:claude-opus-4.6 Reviewed-by: Alex Hung Signed-off-by: Harry Wentland Signed-off-by: Ray Wu Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher (cherry picked from commit 6ab4c36a522842ff70474a1c0af2e40e50fc8300) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

drm/amd/display: Clamp VBIOS HDMI retimer register count to array size

2026-06-19T11:33:39+00:00

commit fb0707ce00eef4e2d60c3020e1c0432739703e4a upstream. [Why & How] The VBIOS integrated info tables (v1_11 and v2_1) contain HdmiRegNum and Hdmi6GRegNum fields that are used as loop bounds when copying retimer I2C register settings into fixed-size arrays (dp*_ext_hdmi_reg_settings[9] and dp*_ext_hdmi_6g_reg_settings[3]). These u8 fields are not validated before use, so a malformed VBIOS can specify values up to 255, causing an out-of-bounds heap write during driver probe. Clamp each register count to the destination array size using min_t() before the copy loops, in both get_integrated_info_v11() and get_integrated_info_v2_1(). Assisted-by: GitHub Copilot:claude-opus-4.6 Reviewed-by: Alex Hung Signed-off-by: Harry Wentland Signed-off-by: Ray Wu Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher (cherry picked from commit 5a7f0ef90195940c54b0f5bb85b87da55f038c69) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

drm/amd/display: Clamp HDMI HDCP2 rx_id_list read to buffer size

2026-06-19T11:33:39+00:00

commit f0f3981c43b32cadfe373d636d9e9ca522bb3702 upstream. [Why & How] During HDCP 2.x repeater authentication over HDMI, the driver reads the sink's RxStatus register and extracts a 10-bit message size field (max value 1023). This value is used as the read length for the ReceiverID list without being clamped to the size of the destination buffer rx_id_list[177]. A malicious HDMI repeater could advertise a message size larger than the buffer, causing an out-of-bounds write during the I2C read. Clamp the read length in mod_hdcp_read_rx_id_list() to the size of the rx_id_list buffer, matching the approach already used in the DP branch. Fixes: eff682f83c9c ("drm/amd/display: Add DDC handles for HDCP2.2") Assisted-by: Copilot:claude-opus-4.6 Reviewed-by: Alex Hung Signed-off-by: Harry Wentland Signed-off-by: Ray Wu Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher (cherry picked from commit 229212219e4247d9486f8ba41ef087358490be09) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

drm/amd/display: Reject gpio_bitshift >= 32 in bios_parser_get_gpio_pin_info()

2026-06-19T11:33:37+00:00

commit 49c3da65961fe9857c831d47fa1989084e87514a upstream. [Why & How] gpio_bitshift is a uint8_t read directly from the VBIOS GPIO pin table. If the value is >= 32, the expression "1 << gpio_bitshift" triggers undefined behaviour in C (shift count exceeds type width). On x86 the shift is silently masked to 5 bits, producing an incorrect GPIO mask that may cause wrong MMIO register bits to be toggled. Validate gpio_bitshift before use and return BP_RESULT_BADBIOSTABLE for out-of-range values. Fixes: ae79c310b1a6 ("drm/amd/display: Add DCE12 bios parser support") Assisted-by: Copilot:claude-opus-4.6 Reviewed-by: Alex Hung Signed-off-by: Harry Wentland Signed-off-by: Ray Wu Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher (cherry picked from commit eadf438ab8d370b9d19acee9359918c85afeb80d) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

drm/amd/display: Validate payload length and link_index in dc_process_dmub_aux_transfer_async

2026-06-01T15:35:48+00:00

commit 6c92f6d9600efa3ef0d9e560a2b52776d9803c29 upstream. [Why&How] dc_process_dmub_aux_transfer_async() copies payload->length bytes into a 16-byte stack buffer (dpaux.data[16]) guarded only by an ASSERT(), which is a no-op in release builds. If a caller ever passes length > 16 this results in a stack buffer overflow via memcpy. Additionally, link_index is used to dereference dc->links[] without bounds checking against dc->link_count, risking an out-of-bounds access. Replace the ASSERT with a hard runtime check that returns false when payload->length exceeds the destination buffer size, and add a bounds check for link_index before it is used. Assisted-by: GitHub Copilot:Claude claude-4-opus Reviewed-by: Alex Hung Signed-off-by: Harry Wentland Signed-off-by: Ivan Lipski Tested-by: Dan Wheeler Signed-off-by: Alex Deucher (cherry picked from commit ba4caa9fecdf7a38f98c878ad05a8a64148b6881) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

drm/amd/display: Fix integer overflow in bios_get_image()

2026-06-01T15:35:48+00:00

commit cd86529ec61474a38c3837fb7823790a7c3f8cce upstream. [Why&How] The bounds check in bios_get_image() computes 'offset + size' using unsigned 32-bit arithmetic before comparing against bios_size. If a VBIOS image contains a near-UINT32_MAX offset the addition wraps to a small value, the comparison passes, and the function returns a wild pointer past the VBIOS mapping. Additionally, the comparison uses '<' (strict), which incorrectly rejects the valid exact-fit case where offset + size == bios_size. Fix both issues by restructuring the check to avoid the addition entirely: first reject if offset alone exceeds bios_size, then check size against the remaining space (bios_size - offset). This eliminates the overflow and correctly permits exact-fit accesses. Assisted-by: GitHub Copilot:claude-opus-4.6 Reviewed-by: Alex Hung Signed-off-by: Harry Wentland Signed-off-by: Ivan Lipski Tested-by: Dan Wheeler Signed-off-by: Alex Deucher (cherry picked from commit d40fb392af659c4a02b560319f226842f6ec1a95) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman