diff options
| author | Gao Xiang <gaoxiang25@huawei.com> | 2019-08-21 22:01:52 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-08-21 09:12:42 -0700 |
| commit | e12a0ce2fa69798194f3a8628baf6edfbd5c548f (patch) | |
| tree | 92ea2026443650c6eee452dccdfbefe6260abf9f /drivers | |
| parent | 8467c3b456b57fcb4b3179c34c20cbc9c88956c5 (diff) | |
staging: erofs: detect potential multiref due to corrupted images
As reported by erofs-utils fuzzer, currently, multiref
(ondisk deduplication) hasn't been supported for now,
we should forbid it properly.
Fixes: 3883a79abd02 ("staging: erofs: introduce VLE decompression support")
Cc: <stable@vger.kernel.org> # 4.19+
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Link: https://lore.kernel.org/r/20190821140152.229648-1-gaoxiang25@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/staging/erofs/zdata.c | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/drivers/staging/erofs/zdata.c b/drivers/staging/erofs/zdata.c index 4d6faaab04f5..60d7c20db87d 100644 --- a/drivers/staging/erofs/zdata.c +++ b/drivers/staging/erofs/zdata.c @@ -798,6 +798,7 @@ static int z_erofs_decompress_pcluster(struct super_block *sb, for (i = 0; i < nr_pages; ++i) pages[i] = NULL; + err = 0; z_erofs_pagevec_ctor_init(&ctor, Z_EROFS_NR_INLINE_PAGEVECS, cl->pagevec, 0); @@ -819,8 +820,17 @@ static int z_erofs_decompress_pcluster(struct super_block *sb, pagenr = z_erofs_onlinepage_index(page); DBG_BUGON(pagenr >= nr_pages); - DBG_BUGON(pages[pagenr]); + /* + * currently EROFS doesn't support multiref(dedup), + * so here erroring out one multiref page. + */ + if (unlikely(pages[pagenr])) { + DBG_BUGON(1); + SetPageError(pages[pagenr]); + z_erofs_onlinepage_endio(pages[pagenr]); + err = -EFSCORRUPTED; + } pages[pagenr] = page; } z_erofs_pagevec_ctor_exit(&ctor, true); @@ -828,7 +838,6 @@ static int z_erofs_decompress_pcluster(struct super_block *sb, overlapped = false; compressed_pages = pcl->compressed_pages; - err = 0; for (i = 0; i < clusterpages; ++i) { unsigned int pagenr; @@ -852,7 +861,12 @@ static int z_erofs_decompress_pcluster(struct super_block *sb, pagenr = z_erofs_onlinepage_index(page); DBG_BUGON(pagenr >= nr_pages); - DBG_BUGON(pages[pagenr]); + if (unlikely(pages[pagenr])) { + DBG_BUGON(1); + SetPageError(pages[pagenr]); + z_erofs_onlinepage_endio(pages[pagenr]); + err = -EFSCORRUPTED; + } pages[pagenr] = page; overlapped = true; |