KASAN: slab-out-of-bounds Read in reiserfs_xattr

Kernel	Title	Rank 🛈	Count	Last	Reported	Patched	Status
linux-6.1	KASAN: slab-out-of-bounds Read in reiserfs_xattr_get	17	1	478d	478d	0/3	auto-obsoleted due to no activity on 2025/03/30 06:16
linux-6.6	KASAN: slab-out-of-bounds Read in reiserfs_xattr_get	17	2	172d	199d	0/2	auto-obsoleted due to no activity on 2026/01/30 03:22
linux-5.15	KASAN: slab-out-of-bounds Read in reiserfs_xattr_get	17	3	361d	435d	0/3	auto-obsoleted due to no activity on 2025/07/24 22:48
upstream	KASAN: slab-out-of-bounds Read in reiserfs_xattr_get (2) fs	17	1	805d	801d	0/29	auto-obsoleted due to no activity on 2024/05/07 19:35
upstream	KASAN: slab-out-of-bounds Read in reiserfs_xattr_get fs	19	106	939d	1825d	0/29	auto-obsoleted due to no activity on 2023/12/25 15:39

loop5: detected capacity change from 0 to 32768
==================================================================
BUG: KASAN: slab-out-of-bounds in reiserfs_xattr_get+0xfa/0x5a0 fs/reiserfs/xattr.c:674
Read of size 8 at addr ffff88804a873d98 by task syz.5.13521/14900

CPU: 1 PID: 14900 Comm: syz.5.13521 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:316 [inline]
 print_report+0xa8/0x210 mm/kasan/report.c:420
 kasan_report+0x10b/0x140 mm/kasan/report.c:524
 reiserfs_xattr_get+0xfa/0x5a0 fs/reiserfs/xattr.c:674
 reiserfs_get_acl+0x7a/0x680 fs/reiserfs/xattr_acl.c:214
 get_acl+0x154/0x250 fs/posix_acl.c:153
 check_acl+0x3a/0x150 fs/namei.c:309
 acl_permission_check fs/namei.c:354 [inline]
 generic_permission+0x3bf/0x510 fs/namei.c:407
 do_inode_permission fs/namei.c:461 [inline]
 inode_permission+0x239/0x480 fs/namei.c:528
 may_open+0x262/0x400 fs/namei.c:3262
 do_open fs/namei.c:3632 [inline]
 path_openat+0x24d0/0x2ee0 fs/namei.c:3791
 do_filp_open+0x1f1/0x430 fs/namei.c:3818
 do_sys_openat2+0x150/0x4b0 fs/open.c:1320
 do_sys_open fs/open.c:1336 [inline]
 __do_sys_openat fs/open.c:1352 [inline]
 __se_sys_openat fs/open.c:1347 [inline]
 __x64_sys_openat+0x135/0x160 fs/open.c:1347
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f3a9635cfce
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007f3a9727ada8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f3a9727b6c0 RCX: 00007f3a9635cfce
RDX: 0000000000010000 RSI: 0000200000000540 RDI: ffffffffffffff9c
RBP: 0000200000005e00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000000540
R13: 00007f3a9727aea0 R14: 0000000000005eca R15: 0000200000000000
 </TASK>

Allocated by task 14858:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 ____kasan_kmalloc mm/kasan/common.c:375 [inline]
 __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:384
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 __do_kmalloc_node mm/slab_common.c:936 [inline]
 __kmalloc+0xb0/0x240 mm/slab_common.c:949
 kmalloc include/linux/slab.h:568 [inline]
 ext4_mb_add_groupinfo+0x1ed/0xef0 fs/ext4/mballoc.c:3141
 ext4_mb_init_backend fs/ext4/mballoc.c:3235 [inline]
 ext4_mb_init+0x15ef/0x25a0 fs/ext4/mballoc.c:3531
 __ext4_fill_super fs/ext4/super.c:5476 [inline]
 ext4_fill_super+0x68bf/0x7dc0 fs/ext4/super.c:5687
 get_tree_bdev+0x3f1/0x610 fs/super.c:1366
 vfs_get_tree+0x88/0x270 fs/super.c:1573
 do_new_mount+0x24a/0xa40 fs/namespace.c:3078
 do_mount fs/namespace.c:3421 [inline]
 __do_sys_mount fs/namespace.c:3629 [inline]
 __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Freed by task 10105:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516
 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:237
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1729 [inline]
 slab_free_freelist_hook+0x131/0x1a0 mm/slub.c:1755
 slab_free mm/slub.c:3687 [inline]
 __kmem_cache_free+0xb6/0x1f0 mm/slub.c:3700
 ext4_mb_release+0x75f/0xf30 fs/ext4/mballoc.c:3607
 ext4_put_super+0x213/0xe90 fs/ext4/super.c:1239
 generic_shutdown_super+0x130/0x340 fs/super.c:501
 kill_block_super+0x7c/0xe0 fs/super.c:1470
 deactivate_locked_super+0x93/0xf0 fs/super.c:332
 cleanup_mnt+0x42c/0x4b0 fs/namespace.c:1191
 task_work_run+0x1d0/0x260 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

The buggy address belongs to the object at ffff88804a873c00
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 152 bytes to the right of
 256-byte region [ffff88804a873c00, ffff88804a873d00)

The buggy address belongs to the physical page:
page:ffffea00012a1c80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x4a872
head:ffffea00012a1c80 order:1 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea0001cc0880 dead000000000004 ffff888017441b40
raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 14059, tgid 14057 (syz.4.13288), ts 1503167557370, free_ts 1503108604273
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2559
 prep_new_page mm/page_alloc.c:2566 [inline]
 get_page_from_freelist+0x1a1e/0x1ab0 mm/page_alloc.c:4357
 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5657
 alloc_slab_page+0x5d/0x160 mm/slub.c:1799
 allocate_slab mm/slub.c:1944 [inline]
 new_slab+0x87/0x2c0 mm/slub.c:1997
 ___slab_alloc+0xbc6/0x1240 mm/slub.c:3154
 __slab_alloc mm/slub.c:3240 [inline]
 slab_alloc_node mm/slub.c:3325 [inline]
 __kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3398
 __do_kmalloc_node mm/slab_common.c:935 [inline]
 __kmalloc+0xa0/0x240 mm/slab_common.c:949
 kmalloc include/linux/slab.h:568 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 new_dir fs/proc/proc_sysctl.c:973 [inline]
 get_subdir fs/proc/proc_sysctl.c:1017 [inline]
 __register_sysctl_table+0x96c/0xe70 fs/proc/proc_sysctl.c:1379
 __addrconf_sysctl_register+0x271/0x3e0 net/ipv6/addrconf.c:7150
 addrconf_sysctl_register+0x15c/0x1b0 net/ipv6/addrconf.c:7197
 ipv6_add_dev+0xbe0/0x1120 net/ipv6/addrconf.c:451
 addrconf_notify+0x634/0xf40 net/ipv6/addrconf.c:3595
 notifier_call_chain kernel/notifier.c:87 [inline]
 raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:455
 call_netdevice_notifiers_extack net/core/dev.c:2052 [inline]
 call_netdevice_notifiers net/core/dev.c:2066 [inline]
 register_netdevice+0x163f/0x1b00 net/core/dev.c:10263
 geneve_configure+0x637/0xa70 drivers/net/geneve.c:1449
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1486 [inline]
 free_pcp_prepare mm/page_alloc.c:1536 [inline]
 free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3413
 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3508
 free_slab mm/slub.c:2036 [inline]
 discard_slab mm/slub.c:2042 [inline]
 __unfreeze_partials+0x1a5/0x200 mm/slub.c:2591
 put_cpu_partial+0x17c/0x250 mm/slub.c:2667
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:306
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737
 slab_alloc_node mm/slub.c:3359 [inline]
 __kmem_cache_alloc_node+0x140/0x260 mm/slub.c:3398
 __do_kmalloc_node mm/slab_common.c:935 [inline]
 __kmalloc+0xa0/0x240 mm/slab_common.c:949
 kmalloc include/linux/slab.h:568 [inline]
 tomoyo_realpath_from_path+0xdf/0x5d0 security/tomoyo/realpath.c:251
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x26f/0x610 security/tomoyo/file.c:822
 security_path_truncate+0xcf/0x120 security/security.c:1226
 handle_truncate fs/namei.c:3291 [inline]
 do_open fs/namei.c:3638 [inline]
 path_openat+0x27dd/0x2ee0 fs/namei.c:3791
 do_filp_open+0x1f1/0x430 fs/namei.c:3818
 do_sys_openat2+0x150/0x4b0 fs/open.c:1320

Memory state around the buggy address:
 ffff88804a873c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88804a873d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88804a873d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                            ^
 ffff88804a873e00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88804a873e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Assets (help?)	Manager	Title
2026/03/25 08:36	linux-6.1.y	f2ddafa93a25	8ee77f7d	.config	console log	report	info	[disk image] [vmlinux] [kernel image]	ci2-linux-6-1-kasan	KASAN: slab-out-of-bounds Read in reiserfs_xattr_get
2026/01/21 16:46	linux-6.1.y	cd9b81672742	8fc37797	.config	console log	report	info	[disk image] [vmlinux] [kernel image]	ci2-linux-6-1-kasan	KASAN: slab-out-of-bounds Read in reiserfs_xattr_get
2025/10/17 21:57	linux-6.1.y	c2fda4b3f577	1c8c8cd8	.config	console log	report	info	[disk image] [vmlinux] [kernel image]	ci2-linux-6-1-kasan	KASAN: slab-out-of-bounds Read in reiserfs_xattr_get
2025/09/26 18:56	linux-6.1.y	7b34dc04e4ff	001c9061	.config	console log	report	info	[disk image] [vmlinux] [kernel image]	ci2-linux-6-1-kasan	KASAN: slab-out-of-bounds Read in reiserfs_xattr_get
2025/08/15 02:35	linux-6.1.y	3594f306da12	1804e95e	.config	console log	report	info	[disk image] [vmlinux] [kernel image]	ci2-linux-6-1-kasan	KASAN: slab-out-of-bounds Read in reiserfs_xattr_get