[syzbot] [jffs2?] kernel BUG in jffs2_link_node_ref

[syzbot <syzbot+860303c982ac004f74f5@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    bd5f485f3f02 Merge tag 'soc-arm-7.3' of git://git.kernel.o..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=17f4ee79580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=e4131490469a78a3
dashboard link: https://syzkaller.appspot.com/bug?extid=860303c982ac004f74f5
compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
userspace arch: i386

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-bd5f485f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/147156575815/vmlinux-bd5f485f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/f8c1c266e68c/bzImage-bd5f485f.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+860303c982ac004f74f5@syzkaller.appspotmail.com

block2mtd: error: cannot open device /dev/loop0
Flash size not aligned to erasesize, reducing to 2043KiB
jffs2: Eep. ofs 0x00000041 not word-aligned!
------------[ cut here ]------------
kernel BUG at fs/jffs2/nodelist.c:614!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 16927 Comm: syz.6.2727 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:jffs2_link_node_ref+0x4a1/0x940 fs/jffs2/nodelist.c:614
Code: 08 44 89 ee 49 8d 6c 24 28 83 e0 fc 89 c7 89 44 24 0c e8 52 e8 89 fe 8b 44 24 0c 44 39 e8 0f 84 cd fd ff ff e8 90 ee 89 fe 90 <0f> 0b e8 88 ee 89 fe 49 8d be 64 01 00 00 48 b8 00 00 00 00 00 fc
RSP: 0018:ffffc90002db77c8 EFLAGS: 00010287
RAX: 000000000001adff RBX: ffff888073efe260 RCX: ffffc9000bc04000
RDX: 0000000000080000 RSI: ffffffff83800bc0 RDI: ffff888020fb8000
RBP: ffffc900066c1070 R08: 0000000000000004 R09: 0000000000000040
R10: 0000000000000041 R11: 0000000000000000 R12: ffffc900066c1048
R13: 0000000000000041 R14: ffff8880251a8000 R15: ffff888073efe268
FS:  0000000000000000(0000) GS:ffff8880969db000(0063) knlGS:00000000f541db40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 000000000c3fd7fc CR3: 0000000051e89000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 jffs2_scan_dirty_space+0x162/0x270 fs/jffs2/nodelist.c:685
 jffs2_scan_eraseblock fs/jffs2/scan.c:736 [inline]
 jffs2_scan_medium+0x189d/0x59d0 fs/jffs2/scan.c:151
 jffs2_build_filesystem fs/jffs2/build.c:112 [inline]
 jffs2_do_mount_fs+0x8a0/0x2300 fs/jffs2/build.c:416
 jffs2_do_fill_super+0x3d4/0xa50 fs/jffs2/fs.c:574
 jffs2_fill_super+0x283/0x370 fs/jffs2/super.c:290
 mtd_get_sb+0x2f0/0x4c0 drivers/mtd/mtdsuper.c:57
 mtd_get_sb_by_nr drivers/mtd/mtdsuper.c:88 [inline]
 get_tree_mtd+0x6f9/0x8a0 drivers/mtd/mtdsuper.c:141
 vfs_get_tree+0x92/0x320 fs/super.c:1947
 fc_mount fs/namespace.c:1198 [inline]
 do_new_mount_fc fs/namespace.c:3772 [inline]
 do_new_mount fs/namespace.c:3848 [inline]
 path_mount+0x7d0/0x24c0 fs/namespace.c:4168
 do_mount fs/namespace.c:4181 [inline]
 __do_sys_mount fs/namespace.c:4397 [inline]
 __se_sys_mount fs/namespace.c:4374 [inline]
 __ia32_sys_mount+0x292/0x310 fs/namespace.c:4374
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:79 [inline]
 __do_fast_syscall_32+0x13a/0x8b0 arch/x86/entry/syscall_32.c:291
 do_fast_syscall_32+0x32/0x70 arch/x86/entry/syscall_32.c:316
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf702efec
Code: Unable to access opcode bytes at 0xf702efc2.
RSP: 002b:00000000f541d50c EFLAGS: 00000292 ORIG_RAX: 0000000000000015
RAX: ffffffffffffffda RBX: 0000000080000900 RCX: 0000000080000800
RDX: 0000000080000a00 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:jffs2_link_node_ref+0x4a1/0x940 fs/jffs2/nodelist.c:614
Code: 08 44 89 ee 49 8d 6c 24 28 83 e0 fc 89 c7 89 44 24 0c e8 52 e8 89 fe 8b 44 24 0c 44 39 e8 0f 84 cd fd ff ff e8 90 ee 89 fe 90 <0f> 0b e8 88 ee 89 fe 49 8d be 64 01 00 00 48 b8 00 00 00 00 00 fc
RSP: 0018:ffffc90002db77c8 EFLAGS: 00010287
RAX: 000000000001adff RBX: ffff888073efe260 RCX: ffffc9000bc04000
RDX: 0000000000080000 RSI: ffffffff83800bc0 RDI: ffff888020fb8000
RBP: ffffc900066c1070 R08: 0000000000000004 R09: 0000000000000040
R10: 0000000000000041 R11: 0000000000000000 R12: ffffc900066c1048
R13: 0000000000000041 R14: ffff8880251a8000 R15: ffff888073efe268
FS:  0000000000000000(0000) GS:ffff8880969db000(0063) knlGS:00000000f541db40
CS:  0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00000000f729ea66 CR3: 0000000051e89000 CR4: 0000000000352ef0


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