linux-kernel - Re: kmemleak for MIPS

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <AANLkTi=YB+nBG7BYuuU+rB9TC-BbWcJ6mVfkxq0iUype@mail.gmail.com>
Date:	Wed, 30 Mar 2011 12:54:11 +0300
From:	Daniel Baluta <daniel.baluta@...il.com>
To:	Maxin John <maxin.john@...il.com>
Cc:	naveen yadav <yad.naveen@...il.com>, linux-mips@...ux-mips.org,
	linux-kernel@...r.kernel.org, linux-mm@...ck.org,
	Catalin Marinas <catalin.marinas@....com>
Subject: Re: kmemleak for MIPS

>> unreferenced object 0x8f90d000 (size 4096):
>>   comm "swapper", pid 1, jiffies 4294937330 (age 815.000s)
>>   hex dump (first 32 bytes):
>>     00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
>>     00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
>>   backtrace:
>>     [<80529644>] alloc_large_system_hash+0x2f8/0x410
>>     [<805383b4>] udp_table_init+0x4c/0x158
>>     [<805384dc>] udp_init+0x1c/0x94
>>     [<8053889c>] inet_init+0x184/0x2a0
>>     [<80100584>] do_one_initcall+0x174/0x1e0
>>     [<8051f348>] kernel_init+0xe4/0x174
>>     [<80103d4c>] kernel_thread_helper+0x10/0x18
>
> If you for the kmemleak scan (via echo) a few times, do you get more
> leaks? The udp_table_init() function looks like it could leak some
> memory but I haven't seen it before. I'm not sure whether this is a
> false positive or a real leak.

Looking again at udp_init_table it seem that a memory leak is possible.
Could you post your .config and the full output of dmesg after booting.

A situation where CONFIG_BASE_SMALL is 0, and
table->mask < UDP_HTABLE_SIZE_MIN - 1 would lead
to a memory leak.

Furthermore, you can add some printks inside udp_init_table
and check what is really happening there. ([1])

thanks,
Daniel.

[1] http://lxr.linux.no/linux+v2.6.38/net/ipv4/udp.c#L2125

thanks,
Daniel.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/