From: Leon Romanovsky <leonro@xxxxxxxxxxxx> Garbage supplied by user will cause to UCMA module provide zero memory size for memcpy(), because it wasn't checked, it will produce unpredictable results in rdma_resolve_addr(). [ 42.873814] BUG: KASAN: null-ptr-deref in rdma_resolve_addr+0xc8/0xfb0 [ 42.874816] Write of size 28 at addr 00000000000000a0 by task resaddr/1044 [ 42.876765] [ 42.876960] CPU: 1 PID: 1044 Comm: resaddr Not tainted 4.16.0-rc1-00057-gaa56a5293d7e #34 [ 42.877840] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.0-0-g63451fca13-prebuilt.qemu-project.org 04/01/2014 [ 42.879691] Call Trace: [ 42.880236] dump_stack+0x5c/0x77 [ 42.880664] kasan_report+0x163/0x380 [ 42.881354] ? rdma_resolve_addr+0xc8/0xfb0 [ 42.881864] memcpy+0x34/0x50 [ 42.882692] rdma_resolve_addr+0xc8/0xfb0 [ 42.883366] ? deref_stack_reg+0x88/0xd0 [ 42.883856] ? vsnprintf+0x31a/0x770 [ 42.884686] ? rdma_bind_addr+0xc40/0xc40 [ 42.885327] ? num_to_str+0x130/0x130 [ 42.885773] ? deref_stack_reg+0x88/0xd0 [ 42.886217] ? __read_once_size_nocheck.constprop.6+0x10/0x10 [ 42.887698] ? unwind_get_return_address_ptr+0x50/0x50 [ 42.888302] ? replace_slot+0x147/0x170 [ 42.889176] ? delete_node+0x12c/0x340 [ 42.890223] ? __radix_tree_lookup+0xa9/0x160 [ 42.891196] ? ucma_resolve_ip+0xb7/0x110 [ 42.891917] ucma_resolve_ip+0xb7/0x110 [ 42.893003] ? ucma_resolve_addr+0x190/0x190 [ 42.893531] ? _copy_from_user+0x5e/0x90 [ 42.894204] ucma_write+0x174/0x1f0 [ 42.895162] ? ucma_resolve_route+0xf0/0xf0 [ 42.896309] ? dequeue_task_fair+0x67e/0xd90 [ 42.897192] ? put_prev_entity+0x7d/0x170 [ 42.897870] ? ring_buffer_record_is_on+0xd/0x20 [ 42.898439] ? tracing_record_taskinfo_skip+0x20/0x50 [ 42.899686] __vfs_write+0xc4/0x350 [ 42.900142] ? kernel_read+0xa0/0xa0 [ 42.900602] ? firmware_map_remove+0xdf/0xdf [ 42.901135] ? do_task_dead+0x5d/0x60 [ 42.901598] ? do_exit+0xcc6/0x1220 [ 42.902789] ? __fget+0xa8/0xf0 [ 42.903190] vfs_write+0xf7/0x280 [ 42.903600] SyS_write+0xa1/0x120 [ 42.904206] ? SyS_read+0x120/0x120 [ 42.905710] ? compat_start_thread+0x60/0x60 [ 42.906423] ? SyS_read+0x120/0x120 [ 42.908716] do_syscall_64+0xeb/0x250 [ 42.910760] entry_SYSCALL_64_after_hwframe+0x21/0x86 [ 42.912735] RIP: 0033:0x7f138b0afe99 [ 42.914734] RSP: 002b:00007f138b799e98 EFLAGS: 00000287 ORIG_RAX: 0000000000000001 [ 42.917134] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f138b0afe99 [ 42.919487] RDX: 000000000000002e RSI: 0000000020000c40 RDI: 0000000000000004 [ 42.922393] RBP: 00007f138b799ec0 R08: 00007f138b79a700 R09: 0000000000000000 [ 42.925266] R10: 00007f138b79a700 R11: 0000000000000287 R12: 00007f138b799fc0 [ 42.927570] R13: 0000000000000000 R14: 00007ffdbae757c0 R15: 00007f138b79a9c0 [ 42.930047] [ 42.932681] Disabling lock debugging due to kernel taint [ 42.934795] BUG: unable to handle kernel NULL pointer dereference at 00000000000000a0 [ 42.936939] IP: memcpy_erms+0x6/0x10 [ 42.938864] PGD 80000001bea92067 P4D 80000001bea92067 PUD 1bea96067 PMD 0 [ 42.941576] Oops: 0002 [#1] SMP KASAN PTI [ 42.943952] CPU: 1 PID: 1044 Comm: resaddr Tainted: G B 4.16.0-rc1-00057-gaa56a5293d7e #34 [ 42.946964] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.0-0-g63451fca13-prebuilt.qemu-project.org 04/01/2014 [ 42.952336] RIP: 0010:memcpy_erms+0x6/0x10 [ 42.954707] RSP: 0018:ffff8801c8b479c8 EFLAGS: 00010286 [ 42.957227] RAX: 00000000000000a0 RBX: ffff8801c8b47ba0 RCX: 000000000000001c [ 42.960543] RDX: 000000000000001c RSI: ffff8801c8b47bbc RDI: 00000000000000a0 [ 42.963867] RBP: ffff8801c8b47b60 R08: 0000000000000000 R09: ffffed0039168ed1 [ 42.967303] R10: 0000000000000001 R11: ffffed0039168ed0 R12: ffff8801c8b47bbc [ 42.970685] R13: 00000000000000a0 R14: 1ffff10039168f4a R15: 0000000000000000 [ 42.973631] FS: 00007f138b79a700(0000) GS:ffff8801e5d00000(0000) knlGS:0000000000000000 [ 42.976831] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 42.979239] CR2: 00000000000000a0 CR3: 00000001be908002 CR4: 00000000003606a0 [ 42.982060] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 42.984877] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 42.988033] Call Trace: [ 42.990487] rdma_resolve_addr+0xc8/0xfb0 [ 42.993202] ? deref_stack_reg+0x88/0xd0 [ 42.996055] ? vsnprintf+0x31a/0x770 [ 42.998707] ? rdma_bind_addr+0xc40/0xc40 [ 43.000985] ? num_to_str+0x130/0x130 [ 43.003410] ? deref_stack_reg+0x88/0xd0 [ 43.006302] ? __read_once_size_nocheck.constprop.6+0x10/0x10 [ 43.008780] ? unwind_get_return_address_ptr+0x50/0x50 [ 43.011178] ? replace_slot+0x147/0x170 [ 43.013517] ? delete_node+0x12c/0x340 [ 43.016019] ? __radix_tree_lookup+0xa9/0x160 [ 43.018755] ? ucma_resolve_ip+0xb7/0x110 [ 43.021270] ucma_resolve_ip+0xb7/0x110 [ 43.023968] ? ucma_resolve_addr+0x190/0x190 [ 43.026312] ? _copy_from_user+0x5e/0x90 [ 43.029384] ucma_write+0x174/0x1f0 [ 43.031861] ? ucma_resolve_route+0xf0/0xf0 [ 43.034782] ? dequeue_task_fair+0x67e/0xd90 [ 43.037483] ? put_prev_entity+0x7d/0x170 [ 43.040215] ? ring_buffer_record_is_on+0xd/0x20 [ 43.042990] ? tracing_record_taskinfo_skip+0x20/0x50 [ 43.045595] __vfs_write+0xc4/0x350 [ 43.048624] ? kernel_read+0xa0/0xa0 [ 43.051604] ? firmware_map_remove+0xdf/0xdf [ 43.055379] ? do_task_dead+0x5d/0x60 [ 43.058000] ? do_exit+0xcc6/0x1220 [ 43.060783] ? __fget+0xa8/0xf0 [ 43.063133] vfs_write+0xf7/0x280 [ 43.065677] SyS_write+0xa1/0x120 [ 43.068647] ? SyS_read+0x120/0x120 [ 43.071179] ? compat_start_thread+0x60/0x60 [ 43.074025] ? SyS_read+0x120/0x120 [ 43.076705] do_syscall_64+0xeb/0x250 [ 43.079006] entry_SYSCALL_64_after_hwframe+0x21/0x86 [ 43.081606] RIP: 0033:0x7f138b0afe99 [ 43.083679] RSP: 002b:00007f138b799e98 EFLAGS: 00000287 ORIG_RAX: 0000000000000001 [ 43.086802] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f138b0afe99 [ 43.089989] RDX: 000000000000002e RSI: 0000000020000c40 RDI: 0000000000000004 [ 43.092866] RBP: 00007f138b799ec0 R08: 00007f138b79a700 R09: 0000000000000000 [ 43.096233] R10: 00007f138b79a700 R11: 0000000000000287 R12: 00007f138b799fc0 [ 43.098913] R13: 0000000000000000 R14: 00007ffdbae757c0 R15: 00007f138b79a9c0 [ 43.101809] Code: 90 90 90 90 90 eb 1e 0f 1f 00 48 89 f8 48 89 d1 48 c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 c3 66 0f 1f 44 00 00 48 89 f8 48 89 d1 <f3> a4 c3 0f 1f 80 00 00 00 00 48 89 f8 48 83 fa 20 72 7e 40 38 [ 43.107950] RIP: memcpy_erms+0x6/0x10 RSP: ffff8801c8b479c8 Reported-by: <syzbot+1d8c43206853b369d00c@xxxxxxxxxxxxxxxxxxxxxxxxx> Fixes: 75216638572f ("RDMA/cma: Export rdma cm interface to userspace") Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx> --- drivers/infiniband/core/ucma.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c index 699a46d4c0c5..3f3f7bbc4528 100644 --- a/drivers/infiniband/core/ucma.c +++ b/drivers/infiniband/core/ucma.c @@ -664,19 +664,23 @@ static ssize_t ucma_resolve_ip(struct ucma_file *file, int in_len, int out_len) { struct rdma_ucm_resolve_ip cmd; + struct sockaddr *src, *dst; struct ucma_context *ctx; int ret; if (copy_from_user(&cmd, inbuf, sizeof(cmd))) return -EFAULT; + src = (struct sockaddr *) &cmd.src_addr; + dst = (struct sockaddr *) &cmd.dst_addr; + if (!rdma_addr_size(src) || !rdma_addr_size(dst)) + return -EINVAL; + ctx = ucma_get_ctx(file, cmd.id); if (IS_ERR(ctx)) return PTR_ERR(ctx); - ret = rdma_resolve_addr(ctx->cm_id, (struct sockaddr *) &cmd.src_addr, - (struct sockaddr *) &cmd.dst_addr, - cmd.timeout_ms); + ret = rdma_resolve_addr(ctx->cm_id, src, dst, cmd.timeout_ms); ucma_put_ctx(ctx); return ret; } -- 2.14.3 -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html