{"id":"AZL-83372","summary":"CVE-2026-31494 affecting package kernel for versions less than 6.6.134.1-2","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: macb: use the current queue number for stats\n\nThere's a potential mismatch between the memory reserved for statistics\nand the amount of memory written.\n\ngem_get_sset_count() correctly computes the number of stats based on the\nactive queues, whereas gem_get_ethtool_stats() indiscriminately copies\ndata using the maximum number of queues, and in the case the number of\nactive queues is less than MACB_MAX_QUEUES, this results in a OOB write\nas observed in the KASAN splat.\n\n==================================================================\nBUG: KASAN: vmalloc-out-of-bounds in gem_get_ethtool_stats+0x54/0x78\n  [macb]\nWrite of size 760 at addr ffff80008080b000 by task ethtool/1027\n\nCPU: [...]\nTainted: [E]=UNSIGNED_MODULE\nHardware name: raspberrypi rpi/rpi, BIOS 2025.10 10/01/2025\nCall trace:\n show_stack+0x20/0x38 (C)\n dump_stack_lvl+0x80/0xf8\n print_report+0x384/0x5e0\n kasan_report+0xa0/0xf0\n kasan_check_range+0xe8/0x190\n __asan_memcpy+0x54/0x98\n gem_get_ethtool_stats+0x54/0x78 [macb\n   926c13f3af83b0c6fe64badb21ec87d5e93fcf65]\n dev_ethtool+0x1220/0x38c0\n dev_ioctl+0x4ac/0xca8\n sock_do_ioctl+0x170/0x1d8\n sock_ioctl+0x484/0x5d8\n __arm64_sys_ioctl+0x12c/0x1b8\n invoke_syscall+0xd4/0x258\n el0_svc_common.constprop.0+0xb4/0x240\n do_el0_svc+0x48/0x68\n el0_svc+0x40/0xf8\n el0t_64_sync_handler+0xa0/0xe8\n el0t_64_sync+0x1b0/0x1b8\n\nThe buggy address belongs to a 1-page vmalloc region starting at\n  0xffff80008080b000 allocated at dev_ethtool+0x11f0/0x38c0\nThe buggy address belongs to the physical page:\npage: refcount:1 mapcount:0 mapping:0000000000000000\n  index:0xffff00000a333000 pfn:0xa333\nflags: 0x7fffc000000000(node=0|zone=0|lastcpupid=0x1ffff)\nraw: 007fffc000000000 0000000000000000 dead000000000122 0000000000000000\nraw: ffff00000a333000 0000000000000000 00000001ffffffff 0000000000000000\npage dumped because: kasan: bad access detected\n\nMemory state around the buggy address:\n ffff80008080b080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00\n ffff80008080b100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00\n\u003effff80008080b180: 00 00 00 00 00 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8\n                                  ^\n ffff80008080b200: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8\n ffff80008080b280: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8\n==================================================================\n\nFix it by making sure the copied size only considers the active number of\nqueues.","modified":"2026-08-28T17:47:34.357335628Z","published":"2026-04-22T14:16:47Z","upstream":["CVE-2026-31494"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-31494"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.134.1-2"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-83372.json"}}],"schema_version":"1.9.0"}