[moderation/CI] Re: bpf: Add value tracking for BPF_DIV

[syzbot ci <syzbot+cia1924fbce9f593a7@syzkaller.appspotmail.com>]

syzbot ci has tested the following series

[v2] bpf: Add value tracking for BPF_DIV
https://lore.kernel.org/all/20251223091120.2413435-1-tangyazhou@zju.edu.cn
* [PATCH bpf-next v2 1/2] bpf: Add interval and tnum analysis for signed and unsigned BPF_DIV
* [PATCH bpf-next v2 2/2] selftests/bpf: Add tests for BPF_DIV analysis

and found the following issue:
WARNING in reg_bounds_sanity_check

Full report is available here:
https://ci.syzbot.org/series/9bfb8ed3-0d6e-4ae4-93a1-e5d466326f9e

***

WARNING in reg_bounds_sanity_check

tree:      bpf-next
URL:       https://kernel.googlesource.com/pub/scm/linux/kernel/git/bpf/bpf-next.git
base:      ec439c38013550420aecc15988ae6acb670838c1
arch:      amd64
compiler:  Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
config:    https://ci.syzbot.org/builds/67e90945-0cc5-47d7-a492-406b63cd4281/config
C repro:   https://ci.syzbot.org/findings/5808370d-6cee-4ff9-9a6f-ba4007533b78/c_repro
syz repro: https://ci.syzbot.org/findings/5808370d-6cee-4ff9-9a6f-ba4007533b78/syz_repro

------------[ cut here ]------------
verifier bug: REG INVARIANTS VIOLATION (alu): range bounds violation u64=[0x1, 0x0] s64=[0x1, 0x0] u32=[0x1, 0x0] s32=[0x1, 0x0] var_off=(0x1, 0x0)
WARNING: kernel/bpf/verifier.c:2748 at reg_bounds_sanity_check+0x201/0xc30 kernel/bpf/verifier.c:2742, CPU#0: syz.0.17/5999
Modules linked in:
CPU: 0 UID: 0 PID: 5999 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:reg_bounds_sanity_check+0x3e6/0xc30 kernel/bpf/verifier.c:2742
Code: 98 00 00 00 4c 8b 8c 24 88 00 00 00 41 ff 34 24 41 57 55 41 55 ff b4 24 f0 00 00 00 ff b4 24 a8 00 00 00 ff b4 24 c0 00 00 00 <67> 48 0f b9 3a 48 83 c4 38 49 bf 00 00 00 00 00 fc ff df 48 8b 84
RSP: 0018:ffffc90004277098 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 1ffff11022c96804 RCX: 0000000000000001
RDX: ffffffff8b71cd00 RSI: ffffffff8b71bae0 RDI: ffffffff8f861280
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001
R10: 000000000000000c R11: 0000000000000000 R12: ffff8881164b4020
R13: 0000000000000001 R14: 1ffff11022c96803 R15: 0000000000000001
FS:  000055555eb0e500(0000) GS:ffff88818e835000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fad443e7dac CR3: 00000001bc680000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 check_alu_op kernel/bpf/verifier.c:16205 [inline]
 do_check_insn kernel/bpf/verifier.c:20533 [inline]
 do_check+0xa72c/0xeba0 kernel/bpf/verifier.c:20802
 do_check_common+0x19cc/0x25b0 kernel/bpf/verifier.c:24080
 do_check_main kernel/bpf/verifier.c:24163 [inline]
 bpf_check+0x5e7a/0x1c300 kernel/bpf/verifier.c:25470
 bpf_prog_load+0x13ba/0x1a10 kernel/bpf/syscall.c:3088
 __sys_bpf+0x5c3/0x8a0 kernel/bpf/syscall.c:6207
 __do_sys_bpf kernel/bpf/syscall.c:6320 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:6318 [inline]
 __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6318
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fad4418f7c9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe64db1fd8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fad443e5fa0 RCX: 00007fad4418f7c9
RDX: 0000000000000094 RSI: 0000200000000340 RDI: 0000000000000005
RBP: 00007fad441f297f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fad443e5fa0 R14: 00007fad443e5fa0 R15: 0000000000000003
 </TASK>
----------------
Code disassembly (best guess):
   0:	98                   	cwtl
   1:	00 00                	add    %al,(%rax)
   3:	00 4c 8b 8c          	add    %cl,-0x74(%rbx,%rcx,4)
   7:	24 88                	and    $0x88,%al
   9:	00 00                	add    %al,(%rax)
   b:	00 41 ff             	add    %al,-0x1(%rcx)
   e:	34 24                	xor    $0x24,%al
  10:	41 57                	push   %r15
  12:	55                   	push   %rbp
  13:	41 55                	push   %r13
  15:	ff b4 24 f0 00 00 00 	push   0xf0(%rsp)
  1c:	ff b4 24 a8 00 00 00 	push   0xa8(%rsp)
  23:	ff b4 24 c0 00 00 00 	push   0xc0(%rsp)
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	48 83 c4 38          	add    $0x38,%rsp
  33:	49 bf 00 00 00 00 00 	movabs $0xdffffc0000000000,%r15
  3a:	fc ff df
  3d:	48                   	rex.W
  3e:	8b                   	.byte 0x8b
  3f:	84                   	.byte 0x84


***

If these findings have caused you to resend the series or submit a
separate fix, please add the following tag to your commit message:
  Tested-by: syzbot@syzkaller.appspotmail.com

---
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