This is a note to let you know that I've just added the patch titled

RDMA/ucma: Check that device is connected prior to access it

to the 4.15-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...

The filename of the patch is: rdma-ucma-check-that-device-is-connected-prior-to-access-it.patch and it can be found in the queue-4.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.

From 4b658d1bbc16605330694bb3ef2570c465ef383d Mon Sep 17 00:00:00 2001

From: Leon Romanovsky leonro@mellanox.com Date: Sun, 25 Mar 2018 11:23:55 +0300 Subject: RDMA/ucma: Check that device is connected prior to access it

From: Leon Romanovsky leonro@mellanox.com

commit 4b658d1bbc16605330694bb3ef2570c465ef383d upstream.

Add missing check that device is connected prior to access it.

[ 55.358652] BUG: KASAN: null-ptr-deref in rdma_init_qp_attr+0x4a/0x2c0 [ 55.359389] Read of size 8 at addr 00000000000000b0 by task qp/618 [ 55.360255] [ 55.360432] CPU: 1 PID: 618 Comm: qp Not tainted 4.16.0-rc1-00071-gcaf61b1b8b88 #91 [ 55.361693] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.0-0-g63451fca13-prebuilt.qemu-project.org 04/01/2014 [ 55.363264] Call Trace: [ 55.363833] dump_stack+0x5c/0x77 [ 55.364215] kasan_report+0x163/0x380 [ 55.364610] ? rdma_init_qp_attr+0x4a/0x2c0 [ 55.365238] rdma_init_qp_attr+0x4a/0x2c0 [ 55.366410] ucma_init_qp_attr+0x111/0x200 [ 55.366846] ? ucma_notify+0xf0/0xf0 [ 55.367405] ? _get_random_bytes+0xea/0x1b0 [ 55.367846] ? urandom_read+0x2f0/0x2f0 [ 55.368436] ? kmem_cache_alloc_trace+0xd2/0x1e0 [ 55.369104] ? refcount_inc_not_zero+0x9/0x60 [ 55.369583] ? refcount_inc+0x5/0x30 [ 55.370155] ? rdma_create_id+0x215/0x240 [ 55.370937] ? _copy_to_user+0x4f/0x60 [ 55.371620] ? mem_cgroup_commit_charge+0x1f5/0x290 [ 55.372127] ? _copy_from_user+0x5e/0x90 [ 55.372720] ucma_write+0x174/0x1f0 [ 55.373090] ? ucma_close_id+0x40/0x40 [ 55.373805] ? __lru_cache_add+0xa8/0xd0 [ 55.374403] __vfs_write+0xc4/0x350 [ 55.374774] ? kernel_read+0xa0/0xa0 [ 55.375173] ? fsnotify+0x899/0x8f0 [ 55.375544] ? fsnotify_unmount_inodes+0x170/0x170 [ 55.376689] ? __fsnotify_update_child_dentry_flags+0x30/0x30 [ 55.377522] ? handle_mm_fault+0x174/0x320 [ 55.378169] vfs_write+0xf7/0x280 [ 55.378864] SyS_write+0xa1/0x120 [ 55.379270] ? SyS_read+0x120/0x120 [ 55.379643] ? mm_fault_error+0x180/0x180 [ 55.380071] ? task_work_run+0x7d/0xd0 [ 55.380910] ? __task_pid_nr_ns+0x120/0x140 [ 55.381366] ? SyS_read+0x120/0x120 [ 55.381739] do_syscall_64+0xeb/0x250 [ 55.382143] entry_SYSCALL_64_after_hwframe+0x21/0x86 [ 55.382841] RIP: 0033:0x7fc2ef803e99 [ 55.383227] RSP: 002b:00007fffcc5f3be8 EFLAGS: 00000217 ORIG_RAX: 0000000000000001 [ 55.384173] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fc2ef803e99 [ 55.386145] RDX: 0000000000000057 RSI: 0000000020000080 RDI: 0000000000000003 [ 55.388418] RBP: 00007fffcc5f3c00 R08: 0000000000000000 R09: 0000000000000000 [ 55.390542] R10: 0000000000000000 R11: 0000000000000217 R12: 0000000000400480 [ 55.392916] R13: 00007fffcc5f3cf0 R14: 0000000000000000 R15: 0000000000000000 [ 55.521088] Code: e5 4d 1e ff 48 89 df 44 0f b6 b3 b8 01 00 00 e8 65 50 1e ff 4c 8b 2b 49 8d bd b0 00 00 00 e8 56 50 1e ff 41 0f b6 c6 48 c1 e0 04 <49> 03 85 b0 00 00 00 48 8d 78 08 48 89 04 24 e8 3a 4f 1e ff 48 [ 55.525980] RIP: rdma_init_qp_attr+0x52/0x2c0 RSP: ffff8801e2c2f9d8 [ 55.532648] CR2: 00000000000000b0 [ 55.534396] ---[ end trace 70cee64090251c0b ]---

Fixes: 75216638572f ("RDMA/cma: Export rdma cm interface to userspace") Fixes: d541e45500bd ("IB/core: Convert ah_attr from OPA to IB when copying to user") Reported-by: syzbot+7b62c837c2516f8f38c8@syzkaller.appspotmail.com Signed-off-by: Leon Romanovsky leonro@mellanox.com Signed-off-by: Jason Gunthorpe jgg@mellanox.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

--- drivers/infiniband/core/ucma.c | 5 +++++ 1 file changed, 5 insertions(+)

--- a/drivers/infiniband/core/ucma.c +++ b/drivers/infiniband/core/ucma.c @@ -1165,6 +1165,11 @@ static ssize_t ucma_init_qp_attr(struct if (IS_ERR(ctx)) return PTR_ERR(ctx);

+ if (!ctx->cm_id->device) { + ret = -EINVAL; + goto out; + } + resp.qp_attr_mask = 0; memset(&qp_attr, 0, sizeof qp_attr); qp_attr.qp_state = cmd.qp_state;

Patches currently in stable-queue which might be from leonro@mellanox.com are

queue-4.15/rdma-ucma-check-af-family-prior-resolving-address.patch queue-4.15/rdma-ucma-check-that-device-is-connected-prior-to-access-it.patch queue-4.15/rdma-ucma-fix-use-after-free-access-in-ucma_close.patch queue-4.15/rdma-ucma-ensure-that-cm_id-exists-prior-to-access-it.patch queue-4.15/rdma-ucma-check-that-device-exists-prior-to-accessing-it.patch