From: Andrew Morton <akpm@linux-foundation.org>
To: Michal Hocko <mhocko@kernel.org>
Cc: Kyungtae Kim <kt0755@gmail.com>,
pavel.tatashin@microsoft.com, vbabka@suse.cz, osalvador@suse.de,
rppt@linux.vnet.ibm.com, aaron.lu@intel.com,
iamjoonsoo.kim@lge.com, alexander.h.duyck@linux.intel.com,
mgorman@techsingularity.net, lifeasageek@gmail.com,
threeearcat@gmail.com, syzkaller@googlegroups.com,
linux-kernel@vger.kernel.org, linux-mm@kvack.org,
Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Subject: Re: UBSAN: Undefined behaviour in mm/page_alloc.c
Date: Tue, 13 Nov 2018 15:15:03 -0800 [thread overview]
Message-ID: <20181113151503.fd370e28cb9df5a0933e9b04@linux-foundation.org> (raw)
In-Reply-To: <20181113094305.GM15120@dhcp22.suse.cz>
On Tue, 13 Nov 2018 10:43:05 +0100 Michal Hocko <mhocko@kernel.org> wrote:
> Konstantin has noticed that kvmalloc might trigger the following warning
> [Thu Nov 1 08:43:56 2018] WARNING: CPU: 0 PID: 6676 at mm/vmstat.c:986 __fragmentation_index+0x54/0x60
> [...]
> [Thu Nov 1 08:43:56 2018] Call Trace:
> [Thu Nov 1 08:43:56 2018] fragmentation_index+0x76/0x90
> [Thu Nov 1 08:43:56 2018] compaction_suitable+0x4f/0xf0
> [Thu Nov 1 08:43:56 2018] shrink_node+0x295/0x310
> [Thu Nov 1 08:43:56 2018] node_reclaim+0x205/0x250
> [Thu Nov 1 08:43:56 2018] get_page_from_freelist+0x649/0xad0
> [Thu Nov 1 08:43:56 2018] ? get_page_from_freelist+0x2d4/0xad0
> [Thu Nov 1 08:43:56 2018] ? release_sock+0x19/0x90
> [Thu Nov 1 08:43:56 2018] ? do_ipv6_setsockopt.isra.5+0x10da/0x1290
> [Thu Nov 1 08:43:56 2018] __alloc_pages_nodemask+0x12a/0x2a0
> [Thu Nov 1 08:43:56 2018] kmalloc_large_node+0x47/0x90
> [Thu Nov 1 08:43:56 2018] __kmalloc_node+0x22b/0x2e0
> [Thu Nov 1 08:43:56 2018] kvmalloc_node+0x3e/0x70
> [Thu Nov 1 08:43:56 2018] xt_alloc_table_info+0x3a/0x80 [x_tables]
> [Thu Nov 1 08:43:56 2018] do_ip6t_set_ctl+0xcd/0x1c0 [ip6_tables]
> [Thu Nov 1 08:43:56 2018] nf_setsockopt+0x44/0x60
> [Thu Nov 1 08:43:56 2018] SyS_setsockopt+0x6f/0xc0
> [Thu Nov 1 08:43:56 2018] do_syscall_64+0x67/0x120
> [Thu Nov 1 08:43:56 2018] entry_SYSCALL_64_after_hwframe+0x3d/0xa2
>
> ...
>
> --- a/mm/page_alloc.c
> +++ b/mm/page_alloc.c
> @@ -4364,6 +4353,15 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, int preferred_nid,
> gfp_t alloc_mask; /* The gfp_t that was actually used for allocation */
> struct alloc_context ac = { };
>
> + /*
> + * There are several places where we assume that the order value is sane
> + * so bail out early if the request is out of bound.
> + */
> + if (unlikely(order >= MAX_ORDER)) {
> + WARN_ON_ONCE(!(gfp_mask & __GFP_NOWARN));
> + return NULL;
> + }
> +
I know "everybody enables CONFIG_DEBUG_VM", but given this is fastpath,
we could help those who choose not to enable it by using
#ifdef CONFIG_DEBUG_VM
if (WARN_ON_ONCE(order >= MAX_ORDER && !(gfp_mask & __GFP_NOWARN)))
return NULL;
#endif
(Again curses 91241681c62 ("include/linux/mmdebug.h: make VM_WARN* non-rvals"))
next prev parent reply other threads:[~2018-11-13 23:15 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-11-09 4:09 UBSAN: Undefined behaviour in mm/page_alloc.c Kyungtae Kim
2018-11-09 8:42 ` Vlastimil Babka
2018-11-09 8:43 ` Michal Hocko
2018-11-09 9:41 ` Tetsuo Handa
2018-11-09 9:56 ` Michal Hocko
2018-11-09 10:07 ` Tetsuo Handa
2018-11-09 10:25 ` Michal Hocko
2018-11-09 10:10 ` Vlastimil Babka
2018-11-09 10:22 ` Michal Hocko
2018-11-09 10:24 ` Tetsuo Handa
2018-11-09 10:28 ` Michal Hocko
2018-11-09 10:52 ` Balbir Singh
2018-11-09 9:56 ` Mel Gorman
2018-11-13 9:43 ` Michal Hocko
2018-11-13 23:15 ` Andrew Morton [this message]
2018-11-13 23:23 ` Vlastimil Babka
2018-11-13 23:32 ` Andrew Morton
2018-11-14 0:05 ` Vlastimil Babka
2018-11-19 23:57 ` Pavel Machek
2018-11-13 23:29 ` Andrew Morton
2018-11-14 7:10 ` Michal Hocko
2018-11-16 23:43 ` Dmitry Vyukov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20181113151503.fd370e28cb9df5a0933e9b04@linux-foundation.org \
--to=akpm@linux-foundation.org \
--cc=aaron.lu@intel.com \
--cc=alexander.h.duyck@linux.intel.com \
--cc=iamjoonsoo.kim@lge.com \
--cc=khlebnikov@yandex-team.ru \
--cc=kt0755@gmail.com \
--cc=lifeasageek@gmail.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mgorman@techsingularity.net \
--cc=mhocko@kernel.org \
--cc=osalvador@suse.de \
--cc=pavel.tatashin@microsoft.com \
--cc=rppt@linux.vnet.ibm.com \
--cc=syzkaller@googlegroups.com \
--cc=threeearcat@gmail.com \
--cc=vbabka@suse.cz \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).