{"id":"CVE-2026-46263","summary":"drm/amd/display: Fix out-of-bounds stream encoder index v3","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/amd/display: Fix out-of-bounds stream encoder index v3\n\neng_id can be negative and that stream_enc_regs[]\ncan be indexed out of bounds.\n\neng_id is used directly as an index into stream_enc_regs[], which has\nonly 5 entries. When eng_id is 5 (ENGINE_ID_DIGF) or negative, this can\naccess memory past the end of the array.\n\nAdd a bounds check using ARRAY_SIZE() before using eng_id as an index.\nThe unsigned cast also rejects negative values.\n\nThis avoids out-of-bounds access.\n\nFixes the below smatch error:\ndcn*_resource.c: stream_encoder_create() may index\nstream_enc_regs[eng_id] out of bounds (size 5).\n\ndrivers/gpu/drm/amd/amdgpu/../display/dc/resource/dcn351/dcn351_resource.c\n    1246 static struct stream_encoder *dcn35_stream_encoder_create(\n    1247         enum engine_id eng_id,\n    1248         struct dc_context *ctx)\n    1249 {\n\n    ...\n\n    1255\n    1256         /* Mapping of VPG, AFMT, DME register blocks to DIO block instance */\n    1257         if (eng_id \u003c= ENGINE_ID_DIGF) {\n\nENGINE_ID_DIGF is 5.  should \u003c= be \u003c?\n\nUnrelated but, ugh, why is Smatch saying that \"eng_id\" can be negative?\nend_id is type signed long, but there are checks in the caller which prevent it from being negative.\n\n    1258                 vpg_inst = eng_id;\n    1259                 afmt_inst = eng_id;\n    1260         } else\n    1261                 return NULL;\n    1262\n\n    ...\n\n    1281\n    1282         dcn35_dio_stream_encoder_construct(enc1, ctx, ctx-\u003edc_bios,\n    1283                                         eng_id, vpg, afmt,\n--\u003e 1284                                         &stream_enc_regs[eng_id],\n                                                  ^^^^^^^^^^^^^^^^^^^^^^^ This stream_enc_regs[] array has 5 elements so we are one element beyond the end of the array.\n\n    ...\n\n    1287         return &enc1-\u003ebase;\n    1288 }\n\nv2: use explicit bounds check as suggested by Roman/Dan; avoid unsigned int cast\n\nv3: The compiler already knows how to compare the two values, so the\n    cast (int) is not needed. (Roman)","modified":"2026-06-18T03:54:45.529484816Z","published":"2026-06-03T15:50:02.572Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46263.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/263e28add4f4472cfa95150d218955d1945aa413"},{"type":"WEB","url":"https://git.kernel.org/stable/c/29f3824b08a98d41ecbbfd33580630d7607f962e"},{"type":"WEB","url":"https://git.kernel.org/stable/c/abde491143e4e12eecc41337910aace4e8d59603"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ca3808d560ad946ab6d089fd1f5bee04b952ead4"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46263.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-46263"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"2728e9c7c84235d2d7bc1403174d071ffc82d6d2"},{"fixed":"29f3824b08a98d41ecbbfd33580630d7607f962e"},{"fixed":"263e28add4f4472cfa95150d218955d1945aa413"},{"fixed":"ca3808d560ad946ab6d089fd1f5bee04b952ead4"},{"fixed":"abde491143e4e12eecc41337910aace4e8d59603"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-46263.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.9.0"},{"fixed":"6.12.75"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.14"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"6.19.4"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-46263.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}