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| author | Sabyrzhan Tasbolatov <snovitoll@gmail.com> | 2021-01-28 14:58:01 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-03-07 14:34:05 +0300 |
| commit | fa5b65609256fee27199c81368e984e48cb5dcfe (patch) | |
| tree | b6ab803e5a843415014a3081fd90e081e900d774 /Documentation/conf.py | |
| parent | 23a523ef400de62e47df37564620ce53a2fb943e (diff) | |
| download | linux-fa5b65609256fee27199c81368e984e48cb5dcfe.tar.xz | |
smackfs: restrict bytes count in smackfs write functions
commit 7ef4c19d245f3dc233fd4be5acea436edd1d83d8 upstream.
syzbot found WARNINGs in several smackfs write operations where
bytes count is passed to memdup_user_nul which exceeds
GFP MAX_ORDER. Check count size if bigger than PAGE_SIZE.
Per smackfs doc, smk_write_net4addr accepts any label or -CIPSO,
smk_write_net6addr accepts any label or -DELETE. I couldn't find
any general rule for other label lengths except SMK_LABELLEN,
SMK_LONGLABEL, SMK_CIPSOMAX which are documented.
Let's constrain, in general, smackfs label lengths for PAGE_SIZE.
Although fuzzer crashes write to smackfs/netlabel on 0x400000 length.
Here is a quick way to reproduce the WARNING:
python -c "print('A' * 0x400000)" > /sys/fs/smackfs/netlabel
Reported-by: syzbot+a71a442385a0b2815497@syzkaller.appspotmail.com
Signed-off-by: Sabyrzhan Tasbolatov <snovitoll@gmail.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'Documentation/conf.py')
0 files changed, 0 insertions, 0 deletions