From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: + fs-minix-dont-allow-getting-deleted-inodes.patch added to -mm tree Date: Tue, 07 Jul 2020 12:25:23 -0700 Message-ID: <20200707192523.vcoGxzMBy%akpm@linux-foundation.org> References: <20200703151445.b6a0cfee402c7c5c4651f1b1@linux-foundation.org> Reply-To: linux-kernel@vger.kernel.org Return-path: Received: from mail.kernel.org ([198.145.29.99]:45060 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728100AbgGGTZY (ORCPT ); Tue, 7 Jul 2020 15:25:24 -0400 In-Reply-To: <20200703151445.b6a0cfee402c7c5c4651f1b1@linux-foundation.org> Sender: mm-commits-owner@vger.kernel.org List-Id: mm-commits@vger.kernel.org To: anenbupt@gmail.com, ebiggers@google.com, mm-commits@vger.kernel.org, stable@vger.kernel.org, viro@zeniv.linux.org.uk The patch titled Subject: fs/minix: don't allow getting deleted inodes has been added to the -mm tree. Its filename is fs-minix-dont-allow-getting-deleted-inodes.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/fs-minix-dont-allow-getting-deleted-inodes.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/fs-minix-dont-allow-getting-deleted-inodes.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Eric Biggers Subject: fs/minix: don't allow getting deleted inodes If an inode has no links, we need to mark it bad rather than allowing it to be accessed. This avoids WARNINGs in inc_nlink() and drop_nlink() when doing directory operations on a fuzzed filesystem. Link: http://lkml.kernel.org/r/20200628060846.682158-3-ebiggers@kernel.org Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot+a9ac3de1b5de5fb10efc@syzkaller.appspotmail.com Reported-by: syzbot+df958cf5688a96ad3287@syzkaller.appspotmail.com Signed-off-by: Eric Biggers Cc: Alexander Viro Cc: Qiujun Huang Cc: Signed-off-by: Andrew Morton --- fs/minix/inode.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) --- a/fs/minix/inode.c~fs-minix-dont-allow-getting-deleted-inodes +++ a/fs/minix/inode.c @@ -468,6 +468,13 @@ static struct inode *V1_minix_iget(struc iget_failed(inode); return ERR_PTR(-EIO); } + if (raw_inode->i_nlinks == 0) { + printk("MINIX-fs: deleted inode referenced: %lu\n", + inode->i_ino); + brelse(bh); + iget_failed(inode); + return ERR_PTR(-ESTALE); + } inode->i_mode = raw_inode->i_mode; i_uid_write(inode, raw_inode->i_uid); i_gid_write(inode, raw_inode->i_gid); @@ -501,6 +508,13 @@ static struct inode *V2_minix_iget(struc iget_failed(inode); return ERR_PTR(-EIO); } + if (raw_inode->i_nlinks == 0) { + printk("MINIX-fs: deleted inode referenced: %lu\n", + inode->i_ino); + brelse(bh); + iget_failed(inode); + return ERR_PTR(-ESTALE); + } inode->i_mode = raw_inode->i_mode; i_uid_write(inode, raw_inode->i_uid); i_gid_write(inode, raw_inode->i_gid); _ Patches currently in -mm which might be from ebiggers@google.com are fs-minix-check-return-value-of-sb_getblk.patch fs-minix-dont-allow-getting-deleted-inodes.patch fs-minix-reject-too-large-maximum-file-size.patch fs-minix-set-s_maxbytes-correctly.patch fs-minix-fix-block-limit-check-for-v1-filesystems.patch fs-minix-remove-expected-error-message-in-block_to_path.patch