From 70376c7ff31221f1d21db5611d8209e677781d3a Mon Sep 17 00:00:00 2001 From: Andreas Gruenbacher Date: Sun, 4 Dec 2022 17:00:04 +0100 Subject: [PATCH] gfs2: Always check inode size of inline inodes Check if the inode size of stuffed (inline) inodes is within the allowed range when reading inodes from disk (gfs2_dinode_in()). This prevents us from on-disk corruption. The two checks in stuffed_readpage() and gfs2_unstuffer_page() that just truncate inline data to the maximum allowed size don't actually make sense, and they can be removed now as well. Reported-by: syzbot+7bb81dfa9cda07d9cd9d@syzkaller.appspotmail.com Signed-off-by: Andreas Gruenbacher --- fs/gfs2/aops.c | 2 -- fs/gfs2/bmap.c | 3 --- fs/gfs2/glops.c | 3 +++ 3 files changed, 3 insertions(+), 5 deletions(-) diff --git a/fs/gfs2/aops.c b/fs/gfs2/aops.c index 05bee80..e782b4f 100644 --- a/fs/gfs2/aops.c +++ b/fs/gfs2/aops.c @@ -427,8 +427,6 @@ static int stuffed_readpage(struct gfs2_inode *ip, struct page *page) return error; kaddr = kmap_atomic(page); - if (dsize > gfs2_max_stuffed_size(ip)) - dsize = gfs2_max_stuffed_size(ip); memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode), dsize); memset(kaddr + dsize, 0, PAGE_SIZE - dsize); kunmap_atomic(kaddr); diff --git a/fs/gfs2/bmap.c b/fs/gfs2/bmap.c index 3bdb2c6..e7537fd 100644 --- a/fs/gfs2/bmap.c +++ b/fs/gfs2/bmap.c @@ -61,9 +61,6 @@ static int gfs2_unstuffer_page(struct gfs2_inode *ip, struct buffer_head *dibh, void *kaddr = kmap(page); u64 dsize = i_size_read(inode); - if (dsize > gfs2_max_stuffed_size(ip)) - dsize = gfs2_max_stuffed_size(ip); - memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode), dsize); memset(kaddr + dsize, 0, PAGE_SIZE - dsize); kunmap(page); diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c index af69a1b..d78b61e 100644 --- a/fs/gfs2/glops.c +++ b/fs/gfs2/glops.c @@ -449,6 +449,9 @@ static int gfs2_dinode_in(struct gfs2_inode *ip, const void *buf) ip->i_depth = (u8)depth; ip->i_entries = be32_to_cpu(str->di_entries); + if (gfs2_is_stuffed(ip) && inode->i_size > gfs2_max_stuffed_size(ip)) + goto corrupt; + if (S_ISREG(inode->i_mode)) gfs2_set_aops(inode); -- 2.7.4