{"id":"AZL-78488","summary":"CVE-2025-40082 affecting package kernel for versions less than 6.6.126.1-1","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nhfsplus: fix slab-out-of-bounds read in hfsplus_uni2asc()\n\nBUG: KASAN: slab-out-of-bounds in hfsplus_uni2asc+0xa71/0xb90 fs/hfsplus/unicode.c:186\nRead of size 2 at addr ffff8880289ef218 by task syz.6.248/14290\n\nCPU: 0 UID: 0 PID: 14290 Comm: syz.6.248 Not tainted 6.16.4 #1 PREEMPT(full)\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014\nCall Trace:\n \u003cTASK\u003e\n __dump_stack lib/dump_stack.c:94 [inline]\n dump_stack_lvl+0x116/0x1b0 lib/dump_stack.c:120\n print_address_description mm/kasan/report.c:378 [inline]\n print_report+0xca/0x5f0 mm/kasan/report.c:482\n kasan_report+0xca/0x100 mm/kasan/report.c:595\n hfsplus_uni2asc+0xa71/0xb90 fs/hfsplus/unicode.c:186\n hfsplus_listxattr+0x5b6/0xbd0 fs/hfsplus/xattr.c:738\n vfs_listxattr+0xbe/0x140 fs/xattr.c:493\n listxattr+0xee/0x190 fs/xattr.c:924\n filename_listxattr fs/xattr.c:958 [inline]\n path_listxattrat+0x143/0x360 fs/xattr.c:988\n do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n do_syscall_64+0xcb/0x4c0 arch/x86/entry/syscall_64.c:94\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\nRIP: 0033:0x7fe0e9fae16d\nCode: 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 \u003c48\u003e 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48\nRSP: 002b:00007fe0eae67f98 EFLAGS: 00000246 ORIG_RAX: 00000000000000c3\nRAX: ffffffffffffffda RBX: 00007fe0ea205fa0 RCX: 00007fe0e9fae16d\nRDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000000\nRBP: 00007fe0ea0480f0 R08: 0000000000000000 R09: 0000000000000000\nR10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000\nR13: 00007fe0ea206038 R14: 00007fe0ea205fa0 R15: 00007fe0eae48000\n \u003c/TASK\u003e\n\nAllocated by task 14290:\n kasan_save_stack+0x24/0x50 mm/kasan/common.c:47\n kasan_save_track+0x14/0x30 mm/kasan/common.c:68\n poison_kmalloc_redzone mm/kasan/common.c:377 [inline]\n __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394\n kasan_kmalloc include/linux/kasan.h:260 [inline]\n __do_kmalloc_node mm/slub.c:4333 [inline]\n __kmalloc_noprof+0x219/0x540 mm/slub.c:4345\n kmalloc_noprof include/linux/slab.h:909 [inline]\n hfsplus_find_init+0x95/0x1f0 fs/hfsplus/bfind.c:21\n hfsplus_listxattr+0x331/0xbd0 fs/hfsplus/xattr.c:697\n vfs_listxattr+0xbe/0x140 fs/xattr.c:493\n listxattr+0xee/0x190 fs/xattr.c:924\n filename_listxattr fs/xattr.c:958 [inline]\n path_listxattrat+0x143/0x360 fs/xattr.c:988\n do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]\n do_syscall_64+0xcb/0x4c0 arch/x86/entry/syscall_64.c:94\n entry_SYSCALL_64_after_hwframe+0x77/0x7f\n\nWhen hfsplus_uni2asc is called from hfsplus_listxattr,\nit actually passes in a struct hfsplus_attr_unistr*.\nThe size of the corresponding structure is different from that of hfsplus_unistr,\nso the previous fix (94458781aee6) is insufficient.\nThe pointer on the unicode buffer is still going beyond the allocated memory.\n\nThis patch introduces two warpper functions hfsplus_uni2asc_xattr_str and\nhfsplus_uni2asc_str to process two unicode buffers,\nstruct hfsplus_attr_unistr* and struct hfsplus_unistr* respectively.\nWhen ustrlen value is bigger than the allocated memory size,\nthe ustrlen value is limited to an safe size.","modified":"2026-08-28T17:47:51.410647673Z","published":"2025-10-28T12:15:42Z","upstream":["CVE-2025-40082"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-40082"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.126.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-78488.json"}}],"schema_version":"1.9.0"}