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... and later at http://ozlabs.org/~akpm/mmotm/broken-out/fs-minix-dont-allow-getting-deleted...

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------------------------------------------------------ From: Eric Biggers ebiggers@google.com 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 ebiggers@google.com Cc: Alexander Viro viro@zeniv.linux.org.uk Cc: Qiujun Huang anenbupt@gmail.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

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