[moderation] [rdma?] KASAN: null-ptr-deref Read in trace_event_raw_event_rtrs_clt_conn_class

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 21d6ac051080 Merge branch 'for-next/core' into for-kernelci
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=15373e79580000
kernel config: https://syzkaller.appspot.com/x/.config?x=d1128bc53f2ef7f3
dashboard link: https://syzkaller.appspot.com/bug?extid=54a179d6b42f78516a13
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8
userspace arch: arm64
CC: [linux-...@vger.kernel.org linux...@vger.kernel.org]

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/88380e2ddcb9/disk-21d6ac05.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/5dba5c2896b7/vmlinux-21d6ac05.xz
kernel image: https://storage.googleapis.com/syzbot-assets/52ac739e37e0/Image-21d6ac05.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+54a179...@syzkaller.appspotmail.com

rtrs_client L2098: <s1>: Failed to resolve address, err: -ENODEV
rtrs_client L2641: <s1>: init_conns() failed: err=-ENODEV path=<invalid address family>@ip:127.0.0.1 [:0]
==================================================================
BUG: KASAN: null-ptr-deref in do_trace_event_raw_event_rtrs_clt_conn_class drivers/infiniband/ulp/rtrs/rtrs-clt-trace.h:58 [inline]
BUG: KASAN: null-ptr-deref in trace_event_raw_event_rtrs_clt_conn_class+0x220/0x480 drivers/infiniband/ulp/rtrs/rtrs-clt-trace.h:36
Read of size 255 at addr 0000000000000000 by task syz.5.434/6914

CPU: 0 UID: 0 PID: 6914 Comm: syz.5.434 Tainted: G L syzkaller #0 PREEMPT
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/07/2026
Call trace:
show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C)
__dump_stack+0x30/0x40 lib/dump_stack.c:94
dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120
print_report+0x58/0x84 mm/kasan/report.c:485
kasan_report+0x8c/0xc4 mm/kasan/report.c:595
check_region_inline mm/kasan/generic.c:-1 [inline]
kasan_check_range+0x17c/0x1ac mm/kasan/generic.c:200
__asan_memcpy+0x3c/0x84 mm/kasan/shadow.c:105
do_trace_event_raw_event_rtrs_clt_conn_class drivers/infiniband/ulp/rtrs/rtrs-clt-trace.h:58 [inline]
trace_event_raw_event_rtrs_clt_conn_class+0x220/0x480 drivers/infiniband/ulp/rtrs/rtrs-clt-trace.h:36
__traceiter_rtrs_clt_close_conns+0x74/0xc8 drivers/infiniband/ulp/rtrs/rtrs-clt-trace.h:77
__do_trace_rtrs_clt_close_conns drivers/infiniband/ulp/rtrs/rtrs-clt-trace.h:77 [inline]
trace_rtrs_clt_close_conns drivers/infiniband/ulp/rtrs/rtrs-clt-trace.h:77 [inline]
rtrs_clt_close_conns+0x2f0/0x40c drivers/infiniband/ulp/rtrs/rtrs-clt.c:1949
rtrs_clt_open+0xa6c/0xd54 drivers/infiniband/ulp/rtrs/rtrs-clt.c:2858
find_and_get_or_create_sess drivers/block/rnbd/rnbd-clt.c:1268 [inline]
rnbd_clt_map_device+0xcb8/0x1f64 drivers/block/rnbd/rnbd-clt.c:1551
rnbd_clt_map_device_store+0x900/0xad8 drivers/block/rnbd/rnbd-clt-sysfs.c:612
dev_attr_store+0x6c/0x90 drivers/base/core.c:2505
sysfs_kf_write+0xe0/0x108 fs/sysfs/file.c:145
kernfs_fop_write_iter+0x260/0x3b8 fs/kernfs/file.c:345
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x51c/0xa0c fs/read_write.c:687
ksys_write+0x12c/0x228 fs/read_write.c:739
__do_sys_write fs/read_write.c:750 [inline]
__se_sys_write fs/read_write.c:747 [inline]
__arm64_sys_write+0x84/0x98 fs/read_write.c:747
__invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49
el0_svc_common+0x19c/0x23c arch/arm64/kernel/syscall.c:121
do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140
el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:758
el0t_64_sync_handler+0x44/0x104 arch/arm64/kernel/entry-common.c:777
el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:590
==================================================================


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