==================================================================
BUG: KASAN: slab-out-of-bounds in jffs2_sum_add_kvec+0x99c/0x11e4 fs/jffs2/summary.c:261
Read of size 4 at addr ffff0000c90b2cbc by task jffs2_gcd_mtd0/10697

CPU: 0 PID: 10697 Comm: jffs2_gcd_mtd0 Not tainted 6.8.0-rc7-syzkaller-g707081b61156 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call trace:
 dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:291
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:298
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x178/0x518 mm/kasan/report.c:488
 kasan_report+0xd8/0x138 mm/kasan/report.c:601
 __asan_report_load4_noabort+0x20/0x2c mm/kasan/report_generic.c:380
 jffs2_sum_add_kvec+0x99c/0x11e4 fs/jffs2/summary.c:261
 jffs2_flash_direct_writev+0xa8/0xe8 fs/jffs2/writev.c:22
 jffs2_flash_writev+0x13c/0x11ac fs/jffs2/wbuf.c:805
 save_xattr_datum+0x3bc/0x780 fs/jffs2/xattr.c:317
 jffs2_garbage_collect_xattr_datum+0x180/0x2f4 fs/jffs2/xattr.c:1248
 jffs2_garbage_collect_pass+0x1110/0x1a50 fs/jffs2/gc.c:337
 jffs2_garbage_collect_thread+0x414/0x48c fs/jffs2/background.c:155
 kthread+0x288/0x310 kernel/kthread.c:388
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860

Allocated by task 10696:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x40/0x78 mm/kasan/common.c:68
 kasan_save_alloc_info+0x40/0x50 mm/kasan/generic.c:575
 poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
 __kasan_kmalloc+0xac/0xc4 mm/kasan/common.c:387
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 __do_kmalloc_node mm/slub.c:3981 [inline]
 __kmalloc+0x2bc/0x5d4 mm/slub.c:3994
 kmalloc include/linux/slab.h:594 [inline]
 kzalloc include/linux/slab.h:711 [inline]
 jffs2_do_mount_fs+0x120/0x1d00 fs/jffs2/build.c:387
 jffs2_do_fill_super+0x480/0x9f8 fs/jffs2/fs.c:573
 jffs2_fill_super+0x248/0x280 fs/jffs2/super.c:289
 mtd_get_sb+0x174/0x398 drivers/mtd/mtdsuper.c:57
 mtd_get_sb_by_nr+0x94/0xb0 drivers/mtd/mtdsuper.c:88
 get_tree_mtd+0x4e4/0x680 drivers/mtd/mtdsuper.c:141
 jffs2_get_tree+0x28/0x38 fs/jffs2/super.c:294
 vfs_get_tree+0x90/0x288 fs/super.c:1779
 do_new_mount+0x278/0x900 fs/namespace.c:3352
 path_mount+0x590/0xe04 fs/namespace.c:3679
 do_mount fs/namespace.c:3692 [inline]
 __do_sys_mount fs/namespace.c:3898 [inline]
 __se_sys_mount fs/namespace.c:3875 [inline]
 __arm64_sys_mount+0x45c/0x594 fs/namespace.c:3875
 __invoke_syscall arch/arm64/kernel/syscall.c:34 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:48
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:133
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:152
 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:712
 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730
 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598

The buggy address belongs to the object at ffff0000c90b2000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 956 bytes to the right of
 allocated 2304-byte region [ffff0000c90b2000, ffff0000c90b2900)

The buggy address belongs to the physical page:
page:00000000d3a9806b refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1090b0
head:00000000d3a9806b order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x5ffc00000000840(slab|head|node=0|zone=2|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 05ffc00000000840 ffff0000c0002140 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000c90b2b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff0000c90b2c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff0000c90b2c80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                        ^
 ffff0000c90b2d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff0000c90b2d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
jffs2: warning: (10697) save_xattr_datum: jffs2_flash_writev()=-22, req=41, wrote=0, at 0x02d034
jffs2: Error garbage collecting node at 0001e050!
jffs2: No space for garbage collection. Aborting GC thread