CVE-2025-38022: RDMA/core: Fix "KASAN: slab-use-after-free Read in ib_register_device" problem

In the Linux kernel, the following vulnerability has been resolved:

RDMA/core: Fix "KASAN: slab-use-after-free Read in ibregisterdevice" problem

Call Trace:

dumpstack lib/dumpstack.c:94 [inline] dumpstacklvl+0x116/0x1f0 lib/dumpstack.c:120 printaddressdescription mm/kasan/report.c:408 [inline] printreport+0xc3/0x670 mm/kasan/report.c:521 kasanreport+0xe0/0x110 mm/kasan/report.c:634 strlen+0x93/0xa0 lib/string.c:420 fortifystrlen include/linux/fortify-string.h:268 [inline] getkobjpathlength lib/kobject.c:118 [inline] kobjectgetpath+0x3f/0x2a0 lib/kobject.c:158 kobjectueventenv+0x289/0x1870 lib/kobjectuevent.c:545 ibregisterdevice drivers/infiniband/core/device.c:1472 [inline] ibregisterdevice+0x8cf/0xe00 drivers/infiniband/core/device.c:1393 rxeregisterdevice+0x275/0x320 drivers/infiniband/sw/rxe/rxeverbs.c:1552 rxenetadd+0x8e/0xe0 drivers/infiniband/sw/rxe/rxenet.c:550 rxenewlink+0x70/0x190 drivers/infiniband/sw/rxe/rxe.c:225 nldevnewlink+0x3a3/0x680 drivers/infiniband/core/nldev.c:1796 rdmanlrcvmsg+0x387/0x6e0 drivers/infiniband/core/netlink.c:195 rdmanlrcvskb.constprop.0.isra.0+0x2e5/0x450 netlinkunicastkernel net/netlink/afnetlink.c:1313 [inline] netlinkunicast+0x53a/0x7f0 net/netlink/afnetlink.c:1339 netlinksendmsg+0x8d1/0xdd0 net/netlink/afnetlink.c:1883 socksendmsgnosec net/socket.c:712 [inline] socksendmsg net/socket.c:727 [inline] syssendmsg+0xa95/0xc70 net/socket.c:2566 syssendmsg+0x134/0x1d0 net/socket.c:2620 syssendmsg+0x16d/0x220 net/socket.c:2652 dosyscallx64 arch/x86/entry/syscall64.c:63 [inline] dosyscall64+0xcd/0x260 arch/x86/entry/syscall64.c:94 entrySYSCALL64afterhwframe+0x77/0x7f

This problem is similar to the problem that the commit 1d6a9e7449e2 ("RDMA/core: Fix use-after-free when rename device name") fixes.

The root cause is: the function ibdevicerename() renames the name with lock. But in the function kobjectuevent(), this name is accessed without lock protection at the same time.

The solution is to add the lock protection when this name is accessed in the function kobjectuevent().