From: Eric Dumazet <eric.dumazet@gmail.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-kernel <linux-kernel@vger.kernel.org>,
Eric Dumazet <edumazet@google.com>,
Eric Dumazet <eric.dumazet@gmail.com>,
Nicholas Piggin <npiggin@gmail.com>
Subject: [PATCH] mm/large system hash: avoid possible NULL deref in alloc_large_system_hash
Date: Wed, 15 Sep 2021 14:25:30 -0700 [thread overview]
Message-ID: <20210915212530.2321545-1-eric.dumazet@gmail.com> (raw)
From: Eric Dumazet <edumazet@google.com>
If __vmalloc() returned NULL, is_vm_area_hugepages(NULL) will fault
if CONFIG_HAVE_ARCH_HUGE_VMALLOC=y
Fixes: 121e6f3258fe ("mm/vmalloc: hugepage vmalloc mappings")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
---
mm/page_alloc.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index b37435c274cf1cb1fabd26465ca7899bb610d91f..e115e21524739341d409b28379942241ed403060 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -8756,7 +8756,8 @@ void *__init alloc_large_system_hash(const char *tablename,
} else if (get_order(size) >= MAX_ORDER || hashdist) {
table = __vmalloc(size, gfp_flags);
virt = true;
- huge = is_vm_area_hugepages(table);
+ if (table)
+ huge = is_vm_area_hugepages(table);
} else {
/*
* If bucketsize is not a power-of-two, we may free
--
2.33.0.309.g3052b89438-goog
reply other threads:[~2021-09-15 21:25 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
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=20210915212530.2321545-1-eric.dumazet@gmail.com \
--to=eric.dumazet@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=edumazet@google.com \
--cc=linux-kernel@vger.kernel.org \
--cc=npiggin@gmail.com \
/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).