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| author | Gao Xiang <hsiangkao@linux.alibaba.com> | 2024-09-12 10:35:38 +0200 |
|---|---|---|
| committer | Gao Xiang <hsiangkao@linux.alibaba.com> | 2024-09-12 17:00:09 +0200 |
| commit | 025497e1d176a9e063d1e60699527e2f3a871935 (patch) | |
| tree | eb633c6a9f65806a38c208e5b1947bc7e4b98df0 /fs/erofs | |
| parent | erofs: restrict pcluster size limitations (diff) | |
| download | linux-025497e1d176a9e063d1e60699527e2f3a871935.tar.xz linux-025497e1d176a9e063d1e60699527e2f3a871935.zip | |
erofs: reject inodes with negative i_size
Negative i_size is never supported, although crafted images with inodes
having negative i_size will NOT lead to security issues in our current
codebase:
The following image can verify this (gzip+base64 encoded):
H4sICCmk4mYAA3Rlc3QuaW1nAGNgGAWjYBSMVPDo4dcH3jP2aTED2TwMKgxMUHHNJY/SQDQX
LxcDIw3tZwXit44MDNpQ/n8gQJZ/vxjijosPuSyZ0DUDgQqcZoKzVYFsDShbHeh6PT29ktTi
Eqz2g/y2pBFiLxDMh4lhs5+W4TAKRsEoGAWjYBSMglEwCkYBPQAAS2DbowAQAAA=
Mark as bad inodes for such corrupted inodes explicitly.
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20240912083538.3011860-1-hsiangkao@linux.alibaba.com
Diffstat (limited to 'fs/erofs')
| -rw-r--r-- | fs/erofs/inode.c | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/fs/erofs/inode.c b/fs/erofs/inode.c index 7a98df664814..db29190656eb 100644 --- a/fs/erofs/inode.c +++ b/fs/erofs/inode.c @@ -5,7 +5,6 @@ * Copyright (C) 2021, Alibaba Cloud */ #include "xattr.h" - #include <trace/events/erofs.h> static int erofs_fill_symlink(struct inode *inode, void *kaddr, @@ -16,7 +15,7 @@ static int erofs_fill_symlink(struct inode *inode, void *kaddr, m_pofs += vi->xattr_isize; /* check if it cannot be handled with fast symlink scheme */ - if (vi->datalayout != EROFS_INODE_FLAT_INLINE || inode->i_size < 0 || + if (vi->datalayout != EROFS_INODE_FLAT_INLINE || check_add_overflow(m_pofs, inode->i_size, &off) || off > i_blocksize(inode)) return 0; @@ -131,6 +130,11 @@ static int erofs_read_inode(struct inode *inode) goto err_out; } + if (unlikely(inode->i_size < 0)) { + erofs_err(sb, "negative i_size @ nid %llu", vi->nid); + err = -EFSCORRUPTED; + goto err_out; + } switch (inode->i_mode & S_IFMT) { case S_IFREG: case S_IFDIR: @@ -186,7 +190,6 @@ static int erofs_read_inode(struct inode *inode) inode->i_blocks = round_up(inode->i_size, sb->s_blocksize) >> 9; else inode->i_blocks = nblks << (sb->s_blocksize_bits - 9); - err_out: DBG_BUGON(err); erofs_put_metabuf(&buf); |