From: Zhu Yanjun yanjun.zhu@linux.dev
[ Upstream commit d0706bfd3ee40923c001c6827b786a309e2a8713 ]
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xc3/0x670 mm/kasan/report.c:521 kasan_report+0xe0/0x110 mm/kasan/report.c:634 strlen+0x93/0xa0 lib/string.c:420 __fortify_strlen include/linux/fortify-string.h:268 [inline] get_kobj_path_length lib/kobject.c:118 [inline] kobject_get_path+0x3f/0x2a0 lib/kobject.c:158 kobject_uevent_env+0x289/0x1870 lib/kobject_uevent.c:545 ib_register_device drivers/infiniband/core/device.c:1472 [inline] ib_register_device+0x8cf/0xe00 drivers/infiniband/core/device.c:1393 rxe_register_device+0x275/0x320 drivers/infiniband/sw/rxe/rxe_verbs.c:1552 rxe_net_add+0x8e/0xe0 drivers/infiniband/sw/rxe/rxe_net.c:550 rxe_newlink+0x70/0x190 drivers/infiniband/sw/rxe/rxe.c:225 nldev_newlink+0x3a3/0x680 drivers/infiniband/core/nldev.c:1796 rdma_nl_rcv_msg+0x387/0x6e0 drivers/infiniband/core/netlink.c:195 rdma_nl_rcv_skb.constprop.0.isra.0+0x2e5/0x450 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x53a/0x7f0 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg net/socket.c:727 [inline] ____sys_sendmsg+0xa95/0xc70 net/socket.c:2566 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2620 __sys_sendmsg+0x16d/0x220 net/socket.c:2652 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+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 ib_device_rename() renames the name with lock. But in the function kobject_uevent(), 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 kobject_uevent().
Fixes: 779e0bf47632 ("RDMA/core: Do not indicate device ready when device enablement fails") Link: https://patch.msgid.link/r/20250506151008.75701-1-yanjun.zhu@linux.dev Reported-by: syzbot+e2ce9e275ecc70a30b72@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=e2ce9e275ecc70a30b72 Signed-off-by: Zhu Yanjun yanjun.zhu@linux.dev Signed-off-by: Jason Gunthorpe jgg@nvidia.com Signed-off-by: Sasha Levin sashal@kernel.org [ Ajay: Modified to apply on v5.10.y-v6.6.y ib_device_notify_register() not present in v5.10.y-v6.6.y, so directly added lock for kobject_uevent() ] Signed-off-by: Ajay Kaher ajay.kaher@broadcom.com Signed-off-by: Shivani Agarwal shivani.agarwal@broadcom.com --- drivers/infiniband/core/device.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/infiniband/core/device.c b/drivers/infiniband/core/device.c index 26f1d2f29..ea9b48108 100644 --- a/drivers/infiniband/core/device.c +++ b/drivers/infiniband/core/device.c @@ -1396,8 +1396,13 @@ int ib_register_device(struct ib_device *device, const char *name, return ret; } dev_set_uevent_suppress(&device->dev, false); + + down_read(&devices_rwsem); + /* Mark for userspace that device is ready */ kobject_uevent(&device->dev.kobj, KOBJ_ADD); + + up_read(&devices_rwsem); ib_device_put(device);
return 0;