{"id":"CVE-2026-90386","summary":"i3c: dw: avoid shift-out-of-bounds when DAA assigns no devices","details":"In the Linux kernel, the following vulnerability has been resolved:\n\ni3c: dw: avoid shift-out-of-bounds when DAA assigns no devices\n\nOn an empty bus ENTDAA assigns nothing, so cmd-\u003erx_len (the count\nof addresses left unassigned) equals master-\u003emaxdevs.\n\nThe GENMASK() index master-\u003emaxdevs - cmd-\u003erx_len - 1 then becomes -1,\nwhich trips up UBSAN. This happens every time on boot on a Gigabyte/AMD\nserver:\n\n    UBSAN: shift-out-of-bounds in drivers/i3c/master/dw-i3c-master.c:905:12\n    shift exponent 64 is too large for 64-bit type 'long unsigned int'\n    CPU: 7 UID: 0 PID: 963 Comm: (udev-worker) Not tainted 7.0.11-200.fc44.x86_64 #1 PREEMPT(lazy)\n    Hardware name: Giga Computing E163-Z34-AAH1-000/MZ33-DC1-000, BIOS R32_F45 04/01/2026\n    Call Trace:\n     \u003cTASK\u003e\n     dump_stack_lvl+0x5d/0x80\n     ubsan_epilogue+0x5/0x2b\n     __ubsan_handle_shift_out_of_bounds.cold+0xd7/0x1ab\n     dw_i3c_master_daa.cold+0x1b/0x96 [dw_i3c_master]\n     i3c_master_do_daa_ext.part.0+0x3e/0xf0 [i3c]\n\nSkip the mask when no new device was assigned.","modified":"2026-09-18T03:48:37.998948408Z","published":"2026-09-17T16:09:21.842Z","database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90386.json"},"references":[{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"},{"type":"WEB","url":"https://git.kernel.org/stable/c/038cf48b3170af26a70bf2dee4f8c3ac910f5176"},{"type":"WEB","url":"https://git.kernel.org/stable/c/111f559e5b6461f5f6977275716e6c5d1eb7ea27"},{"type":"WEB","url":"https://git.kernel.org/stable/c/3a1c35739efb69e8ec2a868113a0471a01bb8f29"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5650b013e6bfc14c8b30be727f4a715b01860a08"},{"type":"WEB","url":"https://git.kernel.org/stable/c/618dd640ded6b94bbdb79c798a901ec564797033"},{"type":"WEB","url":"https://git.kernel.org/stable/c/63110ccc434e10d9e9d2c7d82ebfa8a6f9cedd94"},{"type":"WEB","url":"https://git.kernel.org/stable/c/754533e6169d1f10bdef7a6ba9bd7740b524e1d4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9eaac0cb4ca94e2e32c53c156ae5b813ba7ef90c"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90386.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-90386"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"1dd728f5d4d4b8b53196c1e0fcf86bbaaee39cef"},{"fixed":"5650b013e6bfc14c8b30be727f4a715b01860a08"},{"fixed":"63110ccc434e10d9e9d2c7d82ebfa8a6f9cedd94"},{"fixed":"3a1c35739efb69e8ec2a868113a0471a01bb8f29"},{"fixed":"111f559e5b6461f5f6977275716e6c5d1eb7ea27"},{"fixed":"754533e6169d1f10bdef7a6ba9bd7740b524e1d4"},{"fixed":"9eaac0cb4ca94e2e32c53c156ae5b813ba7ef90c"},{"fixed":"618dd640ded6b94bbdb79c798a901ec564797033"},{"fixed":"038cf48b3170af26a70bf2dee4f8c3ac910f5176"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-90386.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"5.0.0"},{"fixed":"5.10.270"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.221"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.188"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.157"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.110"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.52"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.2.6"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-90386.json"}}],"schema_version":"1.9.0"}