From: Ye Bin Date: Wed, 14 Sep 2022 10:08:11 +0000 (+0800) Subject: jbd2: fix potential buffer head reference count leak X-Git-Tag: v6.6.17~6474^2~30 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=e0d5fc7a6d80ac2406c7dfc6bb625201d0250a8a;p=platform%2Fkernel%2Flinux-rpi.git jbd2: fix potential buffer head reference count leak As in 'jbd2_fc_wait_bufs' if buffer isn't uptodate, will return -EIO without update 'journal->j_fc_off'. But 'jbd2_fc_release_bufs' will release buffer head from ‘j_fc_off - 1’ if 'bh' is NULL will terminal release which will lead to buffer head buffer head reference count leak. To solve above issue, update 'journal->j_fc_off' before return -EIO. Cc: stable@kernel.org Signed-off-by: Ye Bin Reviewed-by: Jan Kara Link: https://lore.kernel.org/r/20220914100812.1414768-2-yebin10@huawei.com Signed-off-by: Theodore Ts'o --- diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index f669ae1..d001930 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -925,8 +925,14 @@ int jbd2_fc_wait_bufs(journal_t *journal, int num_blks) wait_on_buffer(bh); put_bh(bh); journal->j_fc_wbuf[i] = NULL; - if (unlikely(!buffer_uptodate(bh))) + /* + * Update j_fc_off so jbd2_fc_release_bufs can release remain + * buffer head. + */ + if (unlikely(!buffer_uptodate(bh))) { + journal->j_fc_off = i; return -EIO; + } } return 0;