{"id":"DEBIAN-CVE-2021-47497","details":"In the Linux kernel, the following vulnerability has been resolved:  nvmem: Fix shift-out-of-bound (UBSAN) with byte size cells  If a cell has 'nbits' equal to a multiple of BITS_PER_BYTE the logic   *p &= GENMASK((cell-\u003enbits%BITS_PER_BYTE) - 1, 0);  will become undefined behavior because nbits modulo BITS_PER_BYTE is 0, and we subtract one from that making a large number that is then shifted more than the number of bits that fit into an unsigned long.  UBSAN reports this problem:   UBSAN: shift-out-of-bounds in drivers/nvmem/core.c:1386:8  shift exponent 64 is too large for 64-bit type 'unsigned long'  CPU: 6 PID: 7 Comm: kworker/u16:0 Not tainted 5.15.0-rc3+ #9  Hardware name: Google Lazor (rev3+) with KB Backlight (DT)  Workqueue: events_unbound deferred_probe_work_func  Call trace:   dump_backtrace+0x0/0x170   show_stack+0x24/0x30   dump_stack_lvl+0x64/0x7c   dump_stack+0x18/0x38   ubsan_epilogue+0x10/0x54   __ubsan_handle_shift_out_of_bounds+0x180/0x194   __nvmem_cell_read+0x1ec/0x21c   nvmem_cell_read+0x58/0x94   nvmem_cell_read_variable_common+0x4c/0xb0   nvmem_cell_read_variable_le_u32+0x40/0x100   a6xx_gpu_init+0x170/0x2f4   adreno_bind+0x174/0x284   component_bind_all+0xf0/0x264   msm_drm_bind+0x1d8/0x7a0   try_to_bring_up_master+0x164/0x1ac   __component_add+0xbc/0x13c   component_add+0x20/0x2c   dp_display_probe+0x340/0x384   platform_probe+0xc0/0x100   really_probe+0x110/0x304   __driver_probe_device+0xb8/0x120   driver_probe_device+0x4c/0xfc   __device_attach_driver+0xb0/0x128   bus_for_each_drv+0x90/0xdc   __device_attach+0xc8/0x174   device_initial_probe+0x20/0x2c   bus_probe_device+0x40/0xa4   deferred_probe_work_func+0x7c/0xb8   process_one_work+0x128/0x21c   process_scheduled_works+0x40/0x54   worker_thread+0x1ec/0x2a8   kthread+0x138/0x158   ret_from_fork+0x10/0x20  Fix it by making sure there are any bits to mask out.","modified":"2026-09-15T09:02:38.349634289Z","published":"2024-05-22T09:15:11.513Z","upstream":["CVE-2021-47497"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2021-47497"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:12","purl":"pkg:deb/debian/linux?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.14.16-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2021-47497.json"}},{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.14.16-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2021-47497.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"5.14.16-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2021-47497.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}