================================================================== BUG: KASAN: slab-out-of-bounds in __cpa_addr arch/x86/mm/pat/set_memory.c:309 [inline] BUG: KASAN: slab-out-of-bounds in __cpa_addr+0x1d3/0x220 arch/x86/mm/pat/set_memory.c:306 Read of size 8 at addr ffff88804af7c920 by task syz.6.606/8645 CPU: 1 UID: 0 PID: 8645 Comm: syz.6.606 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xcd/0x630 mm/kasan/report.c:482 kasan_report+0xe0/0x110 mm/kasan/report.c:595 __cpa_addr arch/x86/mm/pat/set_memory.c:309 [inline] __cpa_addr+0x1d3/0x220 arch/x86/mm/pat/set_memory.c:306 cpa_flush+0xec/0x8a0 arch/x86/mm/pat/set_memory.c:449 change_page_attr_set_clr arch/x86/mm/pat/set_memory.c:2115 [inline] cpa_clear_pages_array arch/x86/mm/pat/set_memory.c:2144 [inline] set_pages_array_wb+0x238/0x280 arch/x86/mm/pat/set_memory.c:2572 drm_gem_shmem_put_pages_locked+0x27e/0x300 drivers/gpu/drm/drm_gem_shmem_helper.c:239 drm_gem_shmem_vm_close+0x63/0xc0 drivers/gpu/drm/drm_gem_shmem_helper.c:596 vma_close mm/internal.h:190 [inline] remove_vma+0x88/0x160 mm/vma.c:464 exit_mmap+0x50a/0xb90 mm/mmap.c:1305 __mmput+0x12a/0x410 kernel/fork.c:1133 mmput+0x62/0x70 kernel/fork.c:1156 exit_mm kernel/exit.c:582 [inline] do_exit+0x7c7/0x2bf0 kernel/exit.c:954 do_group_exit+0xd3/0x2a0 kernel/exit.c:1107 get_signal+0x2671/0x26d0 kernel/signal.c:3034 arch_do_signal_or_restart+0x8f/0x7c0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x85/0x130 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x419/0x4e0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5e84b8eec9 Code: Unable to access opcode bytes at 0x7f5e84b8ee9f. RSP: 002b:00007f5e85a3a0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 00007f5e84de6188 RCX: 00007f5e84b8eec9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f5e84de6188 RBP: 00007f5e84de6180 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f5e84de6218 R14: 00007ffc75c7fc10 R15: 00007ffc75c7fcf8 Allocated by task 8645: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:400 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:417 kasan_kmalloc include/linux/kasan.h:262 [inline] __do_kmalloc_node mm/slub.c:5603 [inline] __kvmalloc_node_noprof+0x3a3/0x9c0 mm/slub.c:7036 kvmalloc_array_node_noprof include/linux/slab.h:1122 [inline] drm_gem_get_pages+0x144/0xa10 drivers/gpu/drm/drm_gem.c:647 drm_gem_shmem_get_pages_locked+0x1e6/0x490 drivers/gpu/drm/drm_gem_shmem_helper.c:200 drm_gem_shmem_mmap drivers/gpu/drm/drm_gem_shmem_helper.c:646 [inline] drm_gem_shmem_mmap+0xc9/0x550 drivers/gpu/drm/drm_gem_shmem_helper.c:620 drm_gem_mmap_obj+0x1b5/0x560 drivers/gpu/drm/drm_gem.c:1167 drm_gem_mmap+0x40b/0x620 drivers/gpu/drm/drm_gem.c:1245 vfs_mmap include/linux/fs.h:2404 [inline] mmap_file mm/internal.h:167 [inline] __mmap_new_file_vma mm/vma.c:2413 [inline] __mmap_new_vma mm/vma.c:2476 [inline] __mmap_region+0x1309/0x27a0 mm/vma.c:2670 mmap_region+0x1ab/0x3f0 mm/vma.c:2740 do_mmap+0xa3e/0x1210 mm/mmap.c:558 vm_mmap_pgoff+0x29e/0x470 mm/util.c:580 ksys_mmap_pgoff+0x32c/0x5c0 mm/mmap.c:604 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline] __se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline] __x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4e0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88804af7c800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 0 bytes to the right of allocated 288-byte region [ffff88804af7c800, ffff88804af7c920) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4af7c head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88801b026c80 dead000000000100 dead000000000122 raw: 0000000000000000 0000000080100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88801b026c80 dead000000000100 dead000000000122 head: 0000000000000000 0000000080100010 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea00012bdf01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 1089, tgid 1089 (kworker/u8:6), ts 114190906024, free_ts 114186496121 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1850 prep_new_page mm/page_alloc.c:1858 [inline] get_page_from_freelist+0x10a3/0x3a30 mm/page_alloc.c:3884 __alloc_frozen_pages_noprof+0x25f/0x2470 mm/page_alloc.c:5183 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:3030 [inline] allocate_slab mm/slub.c:3203 [inline] new_slab+0x24a/0x360 mm/slub.c:3257 ___slab_alloc+0xdc4/0x1ae0 mm/slub.c:4627 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4746 __slab_alloc_node mm/slub.c:4822 [inline] slab_alloc_node mm/slub.c:5233 [inline] __do_kmalloc_node mm/slub.c:5602 [inline] __kmalloc_noprof+0x501/0x880 mm/slub.c:5615 kmalloc_noprof include/linux/slab.h:961 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] fib6_info_alloc+0x40/0x160 net/ipv6/ip6_fib.c:155 ip6_route_info_create+0x14c/0x870 net/ipv6/route.c:3809 ip6_route_add.part.0+0x22/0x1d0 net/ipv6/route.c:3938 ip6_route_add+0x45/0x60 net/ipv6/route.c:3935 addrconf_prefix_route+0x2fd/0x510 net/ipv6/addrconf.c:2488 addrconf_add_linklocal+0x329/0x500 net/ipv6/addrconf.c:3313 addrconf_addr_gen+0x364/0x3b0 net/ipv6/addrconf.c:3442 addrconf_dev_config net/ipv6/addrconf.c:3489 [inline] addrconf_init_auto_addrs+0x2ba/0x810 net/ipv6/addrconf.c:3567 page last free pid 5852 tgid 5852 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] __free_frozen_pages+0x7df/0x1160 mm/page_alloc.c:2906 stack_depot_save_flags+0x352/0x9c0 lib/stackdepot.c:727 kasan_save_stack+0x42/0x60 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:400 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:417 kasan_kmalloc include/linux/kasan.h:262 [inline] __do_kmalloc_node mm/slub.c:5603 [inline] __kmalloc_noprof+0x32f/0x880 mm/slub.c:5615 kmalloc_noprof include/linux/slab.h:961 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] fib6_info_alloc+0x40/0x160 net/ipv6/ip6_fib.c:155 ip6_route_info_create+0x14c/0x870 net/ipv6/route.c:3809 ip6_route_add.part.0+0x22/0x1d0 net/ipv6/route.c:3938 ip6_route_add+0x45/0x60 net/ipv6/route.c:3935 addrconf_add_mroute+0x1dd/0x350 net/ipv6/addrconf.c:2552 addrconf_add_dev+0x14e/0x1c0 net/ipv6/addrconf.c:2570 addrconf_dev_config net/ipv6/addrconf.c:3479 [inline] addrconf_init_auto_addrs+0x201/0x810 net/ipv6/addrconf.c:3567 addrconf_notify+0x6e2/0x19e0 net/ipv6/addrconf.c:3740 notifier_call_chain+0xbc/0x410 kernel/notifier.c:85 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:2229 Memory state around the buggy address: ffff88804af7c800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88804af7c880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88804af7c900: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88804af7c980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88804af7ca00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================