================================================================== BUG: KASAN: slab-out-of-bounds in firmware_param_path_get+0x348/0x350 drivers/base/firmware_loader/main.c:531 Write of size 1 at addr ffff888118ec3fff by task syz.4.1278/4795 CPU: 1 PID: 4795 Comm: syz.4.1278 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:88 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:427 [inline] kasan_report+0x10f/0x150 mm/kasan/report.c:444 __asan_report_store1_noabort+0x17/0x20 mm/kasan/report_generic.c:311 firmware_param_path_get+0x348/0x350 drivers/base/firmware_loader/main.c:531 param_attr_show+0x150/0x1b0 kernel/params.c:567 module_attr_show+0x56/0x70 kernel/params.c:886 sysfs_kf_seq_show+0x266/0x3d0 fs/sysfs/file.c:61 kernfs_seq_show+0x119/0x160 fs/kernfs/file.c:168 seq_read_iter+0x472/0xce0 fs/seq_file.c:230 kernfs_fop_read_iter+0x146/0x460 fs/kernfs/file.c:241 call_read_iter include/linux/fs.h:2206 [inline] new_sync_read fs/read_write.c:404 [inline] vfs_read+0x6c0/0xc20 fs/read_write.c:485 ksys_read+0x14a/0x260 fs/read_write.c:623 __do_sys_read fs/read_write.c:633 [inline] __se_sys_read fs/read_write.c:631 [inline] __x64_sys_read+0x7b/0x90 fs/read_write.c:631 x64_sys_call+0x96d/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:1 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fad59332f99 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fad57d8c028 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007fad595bafa0 RCX: 00007fad59332f99 RDX: 000000000000204e RSI: 0000200000002440 RDI: 0000000000000003 RBP: 00007fad593c9ec4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fad595bb038 R14: 00007fad595bafa0 R15: 00007ffe6eddabe8 Allocated by task 4787: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:433 [inline] ____kasan_kmalloc mm/kasan/common.c:512 [inline] __kasan_kmalloc+0xd4/0x100 mm/kasan/common.c:521 kasan_kmalloc include/linux/kasan.h:227 [inline] kmem_cache_alloc_trace+0x119/0x270 mm/slub.c:3274 kmalloc include/linux/slab.h:619 [inline] copy_mount_options fs/namespace.c:3245 [inline] __do_sys_mount fs/namespace.c:3583 [inline] __se_sys_mount+0x153/0x390 fs/namespace.c:3565 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3565 x64_sys_call+0x6bf/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:166 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Freed by task 4787: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4a/0x70 mm/kasan/common.c:45 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370 ____kasan_slab_free+0x125/0x160 mm/kasan/common.c:365 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:373 kasan_slab_free include/linux/kasan.h:193 [inline] slab_free_hook mm/slub.c:1728 [inline] slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1754 slab_free mm/slub.c:3526 [inline] kfree+0xc4/0x270 mm/slub.c:4588 __do_sys_mount fs/namespace.c:-1 [inline] __se_sys_mount+0x341/0x390 fs/namespace.c:3565 __x64_sys_mount+0xbf/0xd0 fs/namespace.c:3565 x64_sys_call+0x6bf/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:166 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff888118ec2000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 4095 bytes to the right of 4096-byte region [ffff888118ec2000, ffff888118ec3000) The buggy address belongs to the page: page:ffffea000463b000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x118ec0 head:ffffea000463b000 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head|zone=1) raw: 4000000000010200 0000000000000000 dead000000000122 ffff888100043380 raw: 0000000000000000 0000000080040004 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4752, ts 414285561848, free_ts 413707783543 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2607 prep_new_page+0x1c/0x110 mm/page_alloc.c:2613 get_page_from_freelist+0x2c3a/0x2cd0 mm/page_alloc.c:4487 __alloc_pages+0x1a2/0x460 mm/page_alloc.c:5824 alloc_slab_page mm/slub.c:-1 [inline] allocate_slab mm/slub.c:1937 [inline] new_slab+0xa0/0x4d0 mm/slub.c:2000 ___slab_alloc+0x3ac/0x840 mm/slub.c:3033 __slab_alloc+0x49/0x90 mm/slub.c:3120 slab_alloc_node mm/slub.c:3211 [inline] slab_alloc mm/slub.c:3255 [inline] kmem_cache_alloc_trace+0x146/0x270 mm/slub.c:3272 kmalloc include/linux/slab.h:619 [inline] kzalloc include/linux/slab.h:750 [inline] kobject_uevent_env+0x271/0x700 lib/kobject_uevent.c:539 kvm_uevent_notify_change+0x302/0x3b0 virt/kvm/kvm_main.c:5498 kvm_destroy_vm virt/kvm/kvm_main.c:1219 [inline] kvm_put_kvm+0xa1/0x1190 virt/kvm/kvm_main.c:1283 kvm_vcpu_release+0x57/0x60 virt/kvm/kvm_main.c:3644 __fput+0x22b/0x900 fs/file_table.c:311 ____fput+0x15/0x20 fs/file_table.c:339 task_work_run+0x127/0x190 kernel/task_work.c:188 get_signal+0x13b1/0x1430 kernel/signal.c:2680 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1474 [inline] free_pcp_prepare mm/page_alloc.c:1546 [inline] free_unref_page_prepare+0x5fa/0x600 mm/page_alloc.c:3536 free_unref_page+0xae/0x540 mm/page_alloc.c:3618 free_the_page mm/page_alloc.c:805 [inline] __free_pages+0x6c/0x100 mm/page_alloc.c:5900 __free_slab+0xe5/0x1e0 mm/slub.c:2025 free_slab mm/slub.c:2040 [inline] discard_slab+0x29/0x40 mm/slub.c:2046 __slab_free+0x211/0x290 mm/slub.c:3431 do_slab_free mm/slub.c:3514 [inline] ___cache_free+0x104/0x120 mm/slub.c:3535 qlink_free+0x4d/0x90 mm/kasan/quarantine.c:157 qlist_free_all+0x5f/0xb0 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x14a/0x170 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x2f/0xe0 mm/kasan/common.c:443 kasan_slab_alloc include/linux/kasan.h:217 [inline] slab_post_alloc_hook+0x4f/0x2b0 mm/slab.h:550 slab_alloc_node mm/slub.c:3245 [inline] slab_alloc mm/slub.c:3255 [inline] kmem_cache_alloc+0xf7/0x260 mm/slub.c:3260 getname_flags+0xba/0x510 fs/namei.c:138 user_path_at_empty+0x2f/0x1c0 fs/namei.c:2890 user_path_at include/linux/namei.h:57 [inline] ksys_umount fs/namespace.c:1787 [inline] __do_sys_umount fs/namespace.c:1795 [inline] __se_sys_umount fs/namespace.c:1793 [inline] __x64_sys_umount+0xf9/0x170 fs/namespace.c:1793 Memory state around the buggy address: ffff888118ec3e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888118ec3f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888118ec3f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff888118ec4000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888118ec4080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================