syzbot


KMSAN: uninit-value in ib_nl_handle_ip_res_resp

Status: upstream: reported on 2025/09/30 20:29
Subsystems: rdma
[Documentation on labels]
Reported-by: syzbot+938fcd548c303fe33c1a@syzkaller.appspotmail.com
First crash: 22h25m, last: 20h13m
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [rdma?] KMSAN: uninit-value in ib_nl_handle_ip_res_resp 1 (2) 2025/10/01 03:02

Sample crash report:
netlink: 8 bytes leftover after parsing attributes in process `syz.8.3246'.
=====================================================
BUG: KMSAN: uninit-value in hex_byte_pack include/linux/hex.h:13 [inline]
BUG: KMSAN: uninit-value in ip6_string+0xef4/0x13a0 lib/vsprintf.c:1490
 hex_byte_pack include/linux/hex.h:13 [inline]
 ip6_string+0xef4/0x13a0 lib/vsprintf.c:1490
 ip6_addr_string+0x18a/0x3e0 lib/vsprintf.c:1509
 ip_addr_string+0x245/0xee0 lib/vsprintf.c:1633
 pointer+0xc09/0x1bd0 lib/vsprintf.c:2542
 vsnprintf+0xf8a/0x1bd0 lib/vsprintf.c:2930
 vprintk_store+0x3ae/0x1530 kernel/printk/printk.c:2279
 vprintk_emit+0x307/0xcd0 kernel/printk/printk.c:2426
 vprintk_default+0x3f/0x50 kernel/printk/printk.c:2465
 vprintk+0x36/0x50 kernel/printk/printk_safe.c:82
 _printk+0x17e/0x1b0 kernel/printk/printk.c:2475
 ib_nl_process_good_ip_rsep drivers/infiniband/core/addr.c:128 [inline]
 ib_nl_handle_ip_res_resp+0x963/0x9d0 drivers/infiniband/core/addr.c:141
 rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:-1 [inline]
 rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
 rdma_nl_rcv+0xefa/0x11c0 drivers/infiniband/core/netlink.c:259
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0xf04/0x12b0 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x10b3/0x1250 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x333/0x3d0 net/socket.c:729
 ____sys_sendmsg+0x7e0/0xd80 net/socket.c:2617
 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2671
 __sys_sendmsg+0x1aa/0x300 net/socket.c:2703
 __compat_sys_sendmsg net/compat.c:346 [inline]
 __do_compat_sys_sendmsg net/compat.c:353 [inline]
 __se_compat_sys_sendmsg net/compat.c:350 [inline]
 __ia32_compat_sys_sendmsg+0xa4/0x100 net/compat.c:350
 ia32_sys_call+0x3f6c/0x4310 arch/x86/include/generated/asm/syscalls_32.h:371
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb0/0x150 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/syscall_32.c:331
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:369
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Local variable gid.i created at:
 ib_nl_process_good_ip_rsep drivers/infiniband/core/addr.c:102 [inline]
 ib_nl_handle_ip_res_resp+0x254/0x9d0 drivers/infiniband/core/addr.c:141
 rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:-1 [inline]
 rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
 rdma_nl_rcv+0xefa/0x11c0 drivers/infiniband/core/netlink.c:259

CPU: 0 UID: 0 PID: 17455 Comm: syz.8.3246 Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
=====================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/09/30 11:50 upstream 1896ce8eb6c6 86341da6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in ib_nl_handle_ip_res_resp
2025/09/30 09:38 upstream 1896ce8eb6c6 86341da6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kmsan-gce-386-root KMSAN: uninit-value in ib_nl_handle_ip_res_resp
* Struck through repros no longer work on HEAD.