From: Suren Baghdasaryan <surenb@google.com>
To: akpm@linux-foundation.org
Cc: mhocko@kernel.org, mhocko@suse.com, shy828301@gmail.com,
rientjes@google.com, willy@infradead.org, hannes@cmpxchg.org,
guro@fb.com, riel@surriel.com, minchan@kernel.org,
kirill@shutemov.name, aarcange@redhat.com, brauner@kernel.org,
christian@brauner.io, hch@infradead.org, oleg@redhat.com,
david@redhat.com, jannh@google.com, shakeelb@google.com,
luto@kernel.org, christian.brauner@ubuntu.com,
fweimer@redhat.com, jengelh@inai.de, timmurray@google.com,
linux-mm@kvack.org, linux-kernel@vger.kernel.org,
kernel-team@android.com, surenb@google.com,
syzbot+2ccf63a4bd07cf39cab0@syzkaller.appspotmail.com
Subject: [PATCH 1/1] mm: fix use-after-free bug when mm->mmap is reused after being freed
Date: Tue, 15 Feb 2022 12:19:22 -0800 [thread overview]
Message-ID: <20220215201922.1908156-1-surenb@google.com> (raw)
After exit_mmap frees all vmas in the mm, mm->mmap needs to be reset,
otherwise it points to a vma that was freed and when reused leads to
a use-after-free bug.
Reported-by: syzbot+2ccf63a4bd07cf39cab0@syzkaller.appspotmail.com
Suggested-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
---
mm/mmap.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/mm/mmap.c b/mm/mmap.c
index 1e8fdb0b51ed..d445c1b9d606 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -3186,6 +3186,7 @@ void exit_mmap(struct mm_struct *mm)
vma = remove_vma(vma);
cond_resched();
}
+ mm->mmap = NULL;
mmap_write_unlock(mm);
vm_unacct_memory(nr_accounted);
}
--
2.35.1.265.g69c8d7142f-goog
next reply other threads:[~2022-02-15 20:19 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-15 20:19 Suren Baghdasaryan [this message]
2022-02-15 20:26 ` [PATCH 1/1] mm: fix use-after-free bug when mm->mmap is reused after being freed Rik van Riel
2022-02-15 20:37 ` Andrew Morton
2022-02-15 20:45 ` Suren Baghdasaryan
2022-02-15 20:46 ` Suren Baghdasaryan
2022-02-15 20:51 ` Andrew Morton
2022-02-15 20:42 ` Yang Shi
2022-02-16 7:54 ` Michal Hocko
2022-02-17 19:51 ` Suren Baghdasaryan
2022-02-17 20:50 ` Andrew Morton
2022-02-18 8:11 ` Michal Hocko
2022-02-18 8:10 ` Michal Hocko
2022-02-25 4:18 ` Andrew Morton
2022-02-25 4:23 ` Matthew Wilcox
2022-02-25 5:50 ` Suren Baghdasaryan
2022-03-10 15:55 ` Liam Howlett
2022-03-10 16:28 ` Suren Baghdasaryan
2022-03-10 22:22 ` Liam Howlett
2022-03-10 23:31 ` Suren Baghdasaryan
2022-03-11 1:34 ` Liam Howlett
2022-02-25 10:17 ` Michal Hocko
2022-02-26 1:04 ` Andrew Morton
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=20220215201922.1908156-1-surenb@google.com \
--to=surenb@google.com \
--cc=aarcange@redhat.com \
--cc=akpm@linux-foundation.org \
--cc=brauner@kernel.org \
--cc=christian.brauner@ubuntu.com \
--cc=christian@brauner.io \
--cc=david@redhat.com \
--cc=fweimer@redhat.com \
--cc=guro@fb.com \
--cc=hannes@cmpxchg.org \
--cc=hch@infradead.org \
--cc=jannh@google.com \
--cc=jengelh@inai.de \
--cc=kernel-team@android.com \
--cc=kirill@shutemov.name \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=luto@kernel.org \
--cc=mhocko@kernel.org \
--cc=mhocko@suse.com \
--cc=minchan@kernel.org \
--cc=oleg@redhat.com \
--cc=riel@surriel.com \
--cc=rientjes@google.com \
--cc=shakeelb@google.com \
--cc=shy828301@gmail.com \
--cc=syzbot+2ccf63a4bd07cf39cab0@syzkaller.appspotmail.com \
--cc=timmurray@google.com \
--cc=willy@infradead.org \
/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).