Subject: Re: [Bugme-new] [Bug 27212] New: Warning kmemcheck: Caught 64-bit read from uninitialized memory in netlink_broadcast_filtered

From: Andrew Morton <[email-masked]>
Date: Thu, 20 Jan 2011 12:25:49 -0800

(switched to email.  Please respond via emailed reply-to-all, not via the
bugzilla web interface).

On Thu, 20 Jan 2011 20:08:32 GMT
[email-masked] wrote:

> https://bugzilla.kernel.org/show_bug.cgi?id=27212
> 
>            Summary: Warning kmemcheck: Caught 64-bit read from
>                     uninitialized memory in netlink_broadcast_filtered
>            Product: Other
>            Version: 2.5
>     Kernel Version: 2.6.38-rc1
>           Platform: All
>         OS/Version: Linux
>               Tree: Mainline
>             Status: NEW
>           Severity: normal
>           Priority: P1
>          Component: Other
>         AssignedTo: [email-masked]
>         ReportedBy: [email-masked]
>         Regression: Yes
> 
> 
> Athlon 64 X2 3000 in 64bits
> Slackware64 13.1
> Kernel compiled with kmemcheck and other debug options
> 
> At boot I got the following warning:
> 
> PCI: Using ACPI for IRQ routing
> PCI: pci_cache_line_size set to 64 bytes
> pci 0000:00:00.0: address space collision: [mem 0xe0000000-0xefffffff pref]
> conflicts with GART [mem 0x
> e0000000-0xefffffff]
> reserve RAM buffer: 000000000009fc00 - 000000000009ffff 
> reserve RAM buffer: 000000003ffb0000 - 000000003fffffff
> WARNING: kmemcheck: Caught 64-bit read from uninitialized memory
> (ffff88003e170eb0)
> 0000000000000000010000000000000000000000000000000000000000000000
>  i i i i i i i i i i i i u u u u u u u u u u u u u u u u u u u u
>                                  ^
> 
> Pid: 1, comm: swapper Not tainted 2.6.38-rc1 #2 K8 Combo-Z/K8 Combo-Z
> RIP: 0010:[<ffffffff8127ad72>]  [<ffffffff8127ad72>] memmove+0x122/0x1a0
> RSP: 0018:ffff88003e0b3c60  EFLAGS: 00010202
> RAX: ffff88003e170080 RBX: ffff88003e27b500 RCX: 0000000000000020
> RDX: 0000000000000018 RSI: ffff88003e170ea0 RDI: ffff88003e1700a0
> RBP: ffff88003e0b3c60 R08: 0000000000000001 R09: 0000000000000001
> R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
> R13: 0000000000000080 R14: 0000000000000000 R15: 0000000000000001
> FS:  0000000000000000(0000) GS:ffff88003fc00000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
> CR2: ffff88003e018abc CR3: 0000000001a1c000 CR4: 00000000000006f0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000ffff4ff0 DR7: 0000000000000400
>  [<ffffffff814741c2>] pskb_expand_head+0xc2/0x2a0
>  [<ffffffff81498fa7>] netlink_broadcast_filtered+0xa7/0x4a0
>  [<ffffffff814993b8>] netlink_broadcast+0x18/0x20
>  [<ffffffff8149b884>] genlmsg_mcast+0x144/0x180
>  [<ffffffff8149bc4a>] genl_ctrl_event+0xca/0x450
>  [<ffffffff8149c75d>] genl_register_mc_group+0x10d/0x2a0
>  [<ffffffff81ad9da4>] genl_init+0x6c/0x84
>  [<ffffffff810001de>] do_one_initcall+0x3e/0x170
>  [<ffffffff81aae6ea>] kernel_init+0x197/0x21b
>  [<ffffffff81003254>] kernel_thread_helper+0x4/0x10
>  [<ffffffffffffffff>] 0xffffffffffffffff
> pnp: PnP ACPI init
> ACPI: bus type pnp registered
> pnp 00:00: [bus 00-ff]
> pnp 00:00: [io  0x0cf8-0x0cff]
> 
> This is specific to 2.6.38-rc1.
>