[syzbot] [rdma?] WARNING in res_to_rt

[syzbot] [rdma?] WARNING in res_to_rt

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    ea2bff00da89 Add linux-next specific files for 20260806
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=142d2132580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=b2f9169913eb6d73
dashboard link: https://syzkaller.appspot.com/bug?extid=72eddfbadda3e3928e72
compiler:       Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=14c72fb9580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/473ce49245bc/disk-ea2bff00.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4d5bfcd186f5/vmlinux-ea2bff00.xz
kernel image: https://storage.googleapis.com/syzbot-assets/281694927321/bzImage-ea2bff00.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+72eddfbadda3e3928e72@syzkaller.appspotmail.com

------------[ cut here ]------------
!dev
WARNING: drivers/infiniband/core/restrack.c:138 at res_to_rt+0x1c4/0x230 drivers/infiniband/core/restrack.c:138, CPU#1: kworker/u8:4/59
Modules linked in:
CPU: 1 UID: 0 PID: 59 Comm: kworker/u8:4 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: ib_addr process_one_req
RIP: 0010:res_to_rt+0x1c4/0x230 drivers/infiniband/core/restrack.c:138
Code: 41 5d 41 5e 41 5f c3 cc cc cc cc cc e8 b5 77 f7 f8 48 8d 3d 7e 23 97 07 43 0f b6 44 25 00 84 c0 75 48 8b 33 67 48 0f b9 3a 90 <0f> 0b 90 31 c0 eb cc 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 59 fe ff
RSP: 0018:ffffc9000201f850 EFLAGS: 00010293
RAX: ffffffff88d00ce5 RBX: ffff88807f0fd4f8 RCX: ffff88801e6e0000
RDX: 0000000000000000 RSI: ffffffff8fd996f0 RDI: 0000000000000003
RBP: 0000000000000000 R08: ffff88801e6e0000 R09: 000000000000000a
R10: 0000000000000009 R11: 0000000000000000 R12: dffffc0000000000
R13: 1ffff1100fe1fa9f R14: 0000000000000000 R15: 0000000000000003
FS:  0000000000000000(0000) GS:ffff888125012000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00001d559c3d2000 CR3: 0000000077c4c000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 rdma_restrack_add+0x5a/0x8a0 drivers/infiniband/core/restrack.c:236
 addr_handler+0x41a/0x5a0 drivers/infiniband/core/cma.c:3534
 process_one_req+0x2eb/0x540 drivers/infiniband/core/addr.c:624
 process_one_work kernel/workqueue.c:3375 [inline]
 process_scheduled_works+0xc4e/0x1630 kernel/workqueue.c:3458
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3539
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>


---
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If the report is already addressed, let syzbot know by replying with:
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If you want syzbot to run the reproducer, reply with:
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Re: [syzbot] [rdma?] WARNING in res_to_rt

[Zhu Yanjun]

diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index cc24fddf9aaa..35e463a20ade 100644
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -3531,7 +3531,8 @@ static void addr_handler(int status, struct 
sockaddr *src_addr,
                 if (status)
                         pr_debug_ratelimited("RDMA CM: ADDR_ERROR: 
failed to acquire device. status %d\n",
                                              status);
-               rdma_restrack_add(&id_priv->res);
+               if (id_priv->id.device)
+                       rdma_restrack_add(&id_priv->res);
         } else if (status) {
                 pr_debug_ratelimited("RDMA CM: ADDR_ERROR: failed to 
resolve IP. status %d\n", status);
         }

Re: [syzbot] [rdma?] WARNING in res_to_rt

[Zhu Yanjun]

#syz test: https://github.com/zhuyj/linux.git warning_res_to_rt

Re: [syzbot] [rdma?] WARNING in res_to_rt

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-by: syzbot+72eddfbadda3e3928e72@syzkaller.appspotmail.com
Tested-by: syzbot+72eddfbadda3e3928e72@syzkaller.appspotmail.com

Tested on:

commit:         18e617ee RDMA: Check if device NULL before using
git tree:       https://github.com/zhuyj/linux.git warning_res_to_rt
console output: https://syzkaller.appspot.com/x/log.txt?x=1299dfb9580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=6d343b54cc50df0f
dashboard link: https://syzkaller.appspot.com/bug?extid=72eddfbadda3e3928e72
compiler:       Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8

Note: no patches were applied.
Note: testing is done by a robot and is best-effort only.