[syzbot] [jffs2?] kernel BUG in jffs2_sum_write_sumnode (2)

[syzbot] [jffs2?] kernel BUG in jffs2_sum_write_sumnode (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    89a312991dc6 Merge tag 'cifs-fixes-7.3-rc2' of https://git..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10266f79580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=19560cab9a915237
dashboard link: https://syzkaller.appspot.com/bug?extid=0727f46a0571de01bf93
compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/8722ccd64272/disk-89a31299.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/bb121ca607c4/vmlinux-89a31299.xz
kernel image: https://storage.googleapis.com/syzbot-assets/7e8f64808c5e/bzImage-89a31299.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0727f46a0571de01bf93@syzkaller.appspotmail.com

jffs2: warning: (10801) jffs2_sum_write_sumnode: Empty summary info!!!
------------[ cut here ]------------
------------[ cut here ]------------
kernel BUG at fs/jffs2/summary.c:868!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 10801 Comm: syz.9.661 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/05/2026
RIP: 0010:jffs2_sum_write_sumnode.cold+0x4e/0x174 fs/jffs2/summary.c:868
Code: 0f b6 04 02 84 c0 74 08 3c 03 0f 8e 2c 01 00 00 8b b3 40 06 00 00 48 c7 c2 00 76 33 8c 48 c7 c7 00 72 33 8c e8 cd 73 f8 ff 90 <0f> 0b e8 45 f9 e1 00 65 4c 8b 3d 65 1a 62 13 b8 ff ff 37 00 48 c1
RSP: 0018:ffffc90003a56d90 EFLAGS: 00010282
RAX: 0000000000000046 RBX: ffff8880375f8000 RCX: 0000000000000000
RDX: 0000000000000046 RSI: ffffffff81e9c5d9 RDI: fffff5200074ada3
RBP: ffffc90003a56f10 R08: 0000000000000007 R09: 0000000000000000
R10: 8000000000000000 R11: 0000000000000001 R12: ffff88807e062a00
R13: 0000000000000000 R14: 0000000000000f40 R15: 0000000000000000
FS:  00007f34bbf8d6c0(0000) GS:ffff888123b61000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000557616249078 CR3: 0000000074bae000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 jffs2_do_reserve_space+0xb94/0xf70 fs/jffs2/nodemgmt.c:392
 jffs2_reserve_space_gc+0x6b/0xf0 fs/jffs2/nodemgmt.c:226
 jffs2_garbage_collect_pristine+0x103/0x870 fs/jffs2/gc.c:613
 jffs2_garbage_collect_live+0x1471/0x36b0 fs/jffs2/gc.c:546
 jffs2_garbage_collect_pass+0xb28/0x1b40 fs/jffs2/gc.c:464
 jffs2_reserve_space+0x489/0xbb0 fs/jffs2/nodemgmt.c:171
 jffs2_write_inode_range+0x275/0xb80 fs/jffs2/write.c:362
 jffs2_write_end+0x72c/0xea0 fs/jffs2/file.c:299
 generic_perform_write+0x513/0xa40 mm/filemap.c:4395
 __generic_file_write_iter+0x1f7/0x240 mm/filemap.c:4491
 generic_file_write_iter+0xe1/0x390 mm/filemap.c:4517
 iter_file_splice_write+0x830/0x10b0 fs/splice.c:736
 do_splice_from fs/splice.c:936 [inline]
 direct_splice_actor+0x192/0x690 fs/splice.c:1159
 splice_direct_to_actor+0x345/0xa30 fs/splice.c:1103
 do_splice_direct_actor fs/splice.c:1202 [inline]
 do_splice_direct+0x174/0x240 fs/splice.c:1228
 do_sendfile+0xadc/0xe20 fs/read_write.c:1371
 __do_sys_sendfile64 fs/read_write.c:1432 [inline]
 __se_sys_sendfile64 fs/read_write.c:1418 [inline]
 __x64_sys_sendfile64+0x1d8/0x220 fs/read_write.c:1418
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f34bb19e159
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:00007f34bbf8d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f34bb426090 RCX: 00007f34bb19e159
RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000009
RBP: 00007f34bb235024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000020000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f34bb426128 R14: 00007f34bb426090 R15: 00007ffc4299d258
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:jffs2_sum_write_sumnode.cold+0x4e/0x174 fs/jffs2/summary.c:868
Code: 0f b6 04 02 84 c0 74 08 3c 03 0f 8e 2c 01 00 00 8b b3 40 06 00 00 48 c7 c2 00 76 33 8c 48 c7 c7 00 72 33 8c e8 cd 73 f8 ff 90 <0f> 0b e8 45 f9 e1 00 65 4c 8b 3d 65 1a 62 13 b8 ff ff 37 00 48 c1
RSP: 0018:ffffc90003a56d90 EFLAGS: 00010282
RAX: 0000000000000046 RBX: ffff8880375f8000 RCX: 0000000000000000
RDX: 0000000000000046 RSI: ffffffff81e9c5d9 RDI: fffff5200074ada3
RBP: ffffc90003a56f10 R08: 0000000000000007 R09: 0000000000000000
R10: 8000000000000000 R11: 0000000000000001 R12: ffff88807e062a00
R13: 0000000000000000 R14: 0000000000000f40 R15: 0000000000000000
FS:  00007f34bbf8d6c0(0000) GS:ffff888123c61000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe398fd0000 CR3: 0000000074bae000 CR4: 0000000000350ef0


---
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Re: [syzbot] [jffs2?] kernel BUG in jffs2_sum_write_sumnode (2)

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit:    3857c2fe5449 Merge tag 'pci-v7.3-fixes-4' of git://git.ker..
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=1433f199580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=3e4baf48b1a52e1
dashboard link: https://syzkaller.appspot.com/bug?extid=0727f46a0571de01bf93
compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1233f199580000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0727f46a0571de01bf93@syzkaller.appspotmail.com

block2mtd: Using custom MTD label 'testjffs' for dev /dev/loop0
ftl_cs: FTL header not found.
block2mtd: mtd1: [testjffs] erase_size = 4KiB [4096]
jffs2: notice: (6012) jffs2_build_xattr_subsystem: complete building xattr subsystem, 0 of xdatum (0 unchecked, 0 orphan) and 0 of xref (0 dead, 0 orphan) found.
jffs2: warning: (6012) jffs2_sum_write_sumnode: Empty summary info!!!
------------[ cut here ]------------
kernel BUG at fs/jffs2/summary.c:868!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 1 UID: 0 PID: 6012 Comm: syz-executor253 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
RIP: 0010:jffs2_sum_write_sumnode.cold+0x4e/0x174 fs/jffs2/summary.c:868
Code: 0f b6 04 02 84 c0 74 08 3c 03 0f 8e 2c 01 00 00 8b b3 40 06 00 00 48 c7 c2 80 9d 33 8c 48 c7 c7 80 99 33 8c e8 2d 6e f8 ff 90 <0f> 0b e8 65 49 e2 00 65 4c 8b 3d 45 e4 63 14 b8 ff ff 37 00 48 c1
RSP: 0018:ffffc9000347f9a0 EFLAGS: 00010286
RAX: 0000000000000045 RBX: ffff88802f168000 RCX: 0000000000000000
RDX: 0000000000000045 RSI: ffffffff81ea14b9 RDI: fffff5200068ff25
RBP: ffffc9000347fb20 R08: 0000000000000007 R09: 0000000000000000
R10: 8000000000000000 R11: 0000000000000001 R12: ffff88807b45a080
R13: 0000000000000000 R14: 0000000000000012 R15: 0000000000000000
FS:  0000555557c2d400(0000) GS:ffff888122a44000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ab45d7ad51 CR3: 0000000021ea9000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 jffs2_do_reserve_space+0xb94/0xf70 fs/jffs2/nodemgmt.c:392
 jffs2_reserve_space+0x605/0xbb0 fs/jffs2/nodemgmt.c:201
 jffs2_symlink+0x172/0x1160 fs/jffs2/dir.c:317
 vfs_symlink fs/namei.c:5823 [inline]
 vfs_symlink+0x178/0x4d0 fs/namei.c:5802
 filename_symlinkat+0x2a6/0x560 fs/namei.c:5848
 __do_sys_symlink fs/namei.c:5875 [inline]
 __se_sys_symlink fs/namei.c:5871 [inline]
 __x64_sys_symlink+0x79/0xb0 fs/namei.c:5871
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fda09c12537
Code: 00 00 90 48 83 ec 10 48 63 ff 45 31 c9 45 31 c0 6a 00 31 c9 e8 6a cd 02 00 48 83 c4 18 c3 0f 1f 44 00 00 b8 58 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 d8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffc31fc8508 EFLAGS: 00000206 ORIG_RAX: 0000000000000058
RAX: ffffffffffffffda RBX: 00007ffc31fc85e0 RCX: 00007fda09c12537
RDX: 0000000000000000 RSI: 00007fda09c7eff9 RDI: 00007fda09c7b2b0
RBP: 00007fda09c7ef8c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 00007ffc31fc85e0
R13: 00007fda09c7efa1 R14: 00007fda09ca7cc0 R15: 0000000000000002
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:jffs2_sum_write_sumnode.cold+0x4e/0x174 fs/jffs2/summary.c:868
Code: 0f b6 04 02 84 c0 74 08 3c 03 0f 8e 2c 01 00 00 8b b3 40 06 00 00 48 c7 c2 80 9d 33 8c 48 c7 c7 80 99 33 8c e8 2d 6e f8 ff 90 <0f> 0b e8 65 49 e2 00 65 4c 8b 3d 45 e4 63 14 b8 ff ff 37 00 48 c1
RSP: 0018:ffffc9000347f9a0 EFLAGS: 00010286
RAX: 0000000000000045 RBX: ffff88802f168000 RCX: 0000000000000000
RDX: 0000000000000045 RSI: ffffffff81ea14b9 RDI: fffff5200068ff25
RBP: ffffc9000347fb20 R08: 0000000000000007 R09: 0000000000000000
R10: 8000000000000000 R11: 0000000000000001 R12: ffff88807b45a080
R13: 0000000000000000 R14: 0000000000000012 R15: 0000000000000000
FS:  0000555557c2d400(0000) GS:ffff888122944000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ab45d75950 CR3: 0000000021ea9000 CR4: 0000000000350ef0


---
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