CVE-2026-46055

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> apparmor: Fix string overrun due to missing termination<br /> <br /> When booting Ubuntu 26.04 with Linux 7.0-rc4 on an ARM64 Qualcomm<br /> Snapdragon X1 we see a string buffer overrun:<br /> <br /> BUG: KASAN: slab-out-of-bounds in aa_dfa_match (security/apparmor/match.c:535)<br /> Read of size 1 at addr ffff0008901cc000 by task snap-update-ns/2120<br /> <br /> CPU: 5 UID: 60578 PID: 2120 Comm: snap-update-ns Not tainted 7.0.0-rc4+ #22 PREEMPTLAZY<br /> Hardware name: LENOVO 83ED/LNVNB161216, BIOS NHCN60WW 09/11/2025<br /> Call trace:<br /> show_stack (arch/arm64/kernel/stacktrace.c:501) (C)<br /> dump_stack_lvl (lib/dump_stack.c:122)<br /> print_report (mm/kasan/report.c:379 mm/kasan/report.c:482)<br /> kasan_report (mm/kasan/report.c:597)<br /> __asan_report_load1_noabort (mm/kasan/report_generic.c:378)<br /> aa_dfa_match (security/apparmor/match.c:535)<br /> match_mnt_path_str (security/apparmor/mount.c:244 security/apparmor/mount.c:336)<br /> match_mnt (security/apparmor/mount.c:371)<br /> aa_bind_mount (security/apparmor/mount.c:447 (discriminator 4))<br /> apparmor_sb_mount (security/apparmor/lsm.c:719 (discriminator 1))<br /> security_sb_mount (security/security.c:1062 (discriminator 31))<br /> path_mount (fs/namespace.c:4101)<br /> __arm64_sys_mount (fs/namespace.c:4172 fs/namespace.c:4361 fs/namespace.c:4338 fs/namespace.c:4338)<br /> invoke_syscall.constprop.0 (arch/arm64/kernel/syscall.c:35 arch/arm64/kernel/syscall.c:49)<br /> el0_svc_common.constprop.0 (./include/linux/thread_info.h:142 (discriminator 2) arch/arm64/kernel/syscall.c:140 (discriminator 2))<br /> do_el0_svc (arch/arm64/kernel/syscall.c:152)<br /> el0_svc (arch/arm64/kernel/entry-common.c:80 arch/arm64/kernel/entry-common.c:725)<br /> el0t_64_sync_handler (arch/arm64/kernel/entry-common.c:744)<br /> el0t_64_sync (arch/arm64/kernel/entry.S:596)<br /> <br /> Allocated by task 2120:<br /> kasan_save_stack (mm/kasan/common.c:58)<br /> kasan_save_track (./arch/arm64/include/asm/current.h:19 mm/kasan/common.c:70 mm/kasan/common.c:79)<br /> kasan_save_alloc_info (mm/kasan/generic.c:571)<br /> __kasan_kmalloc (mm/kasan/common.c:419)<br /> __kmalloc_noprof (./include/linux/kasan.h:263 mm/slub.c:5260 mm/slub.c:5272)<br /> aa_get_buffer (security/apparmor/lsm.c:2201)<br /> aa_bind_mount (security/apparmor/mount.c:442)<br /> apparmor_sb_mount (security/apparmor/lsm.c:719 (discriminator 1))<br /> security_sb_mount (security/security.c:1062 (discriminator 31))<br /> path_mount (fs/namespace.c:4101)<br /> __arm64_sys_mount (fs/namespace.c:4172 fs/namespace.c:4361 fs/namespace.c:4338 fs/namespace.c:4338)<br /> invoke_syscall.constprop.0 (arch/arm64/kernel/syscall.c:35 arch/arm64/kernel/syscall.c:49)<br /> el0_svc_common.constprop.0 (./include/linux/thread_info.h:142 (discriminator 2) arch/arm64/kernel/syscall.c:140 (discriminator 2))<br /> do_el0_svc (arch/arm64/kernel/syscall.c:152)<br /> el0_svc (arch/arm64/kernel/entry-common.c:80 arch/arm64/kernel/entry-common.c:725)<br /> el0t_64_sync_handler (arch/arm64/kernel/entry-common.c:744)<br /> el0t_64_sync (arch/arm64/kernel/entry.S:596)<br /> <br /> The buggy address belongs to the object at ffff0008901ca000<br /> which belongs to the cache kmalloc-rnd-06-8k of size 8192<br /> The buggy address is located 0 bytes to the right of<br /> allocated 8192-byte region [ffff0008901ca000, ffff0008901cc000)<br /> <br /> The buggy address belongs to the physical page:<br /> page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x9101c8<br /> head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:-1 pincount:0<br /> flags: 0x8000000000000040(head|zone=2)<br /> page_type: f5(slab)<br /> raw: 8000000000000040 ffff000800016c40 fffffdffe2d14e10 ffff000800015c70<br /> raw: 0000000000000000 0000000800010001 00000000f5000000 0000000000000000<br /> head: 8000000000000040 ffff000800016c40 fffffdffe2d14e10 ffff000800015c70<br /> head: 0000000000000000 0000000800010001 00000000f5000000 0000000000000000<br /> head: 8000000000000003 fffffdffe2407201 fffffdffffffffff 00000000ffffffff<br /> head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008<br /> page dumped because: kasan: bad access detected<br /> <br /> Memory state around the buggy address:<br /> ffff0008901cbf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00<br /> ffff0008<br /> ---truncated---