diff options
| author | Gao Xiang <hsiangkao@linux.alibaba.com> | 2026-04-20 11:46:12 +0800 |
|---|---|---|
| committer | Gao Xiang <hsiangkao@linux.alibaba.com> | 2026-04-21 16:56:08 +0800 |
| commit | c99493ce409c3b98fec1616dbcf24c102e006deb (patch) | |
| tree | f1c95ff458339673a37b504a6af6bb10827fa3c8 | |
| parent | d18a3b5d337fa412a38e776e6b4b857a58836575 (diff) | |
erofs: fix offset truncation when shifting pgoff on 32-bit platforms
On 32-bit platforms, pgoff_t is 32 bits wide, so left-shifting
large arbitrary pgoff_t values by PAGE_SHIFT performs 32-bit arithmetic
and silently truncates the result for pages beyond the 4 GiB boundary.
Cast the page index to loff_t before shifting to produce a correct
64-bit byte offset.
Fixes: 386292919c25 ("erofs: introduce readmore decompression strategy")
Fixes: 307210c262a2 ("erofs: verify metadata accesses for file-backed mounts")
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
| -rw-r--r-- | fs/erofs/data.c | 2 | ||||
| -rw-r--r-- | fs/erofs/zdata.c | 2 |
2 files changed, 2 insertions, 2 deletions
diff --git a/fs/erofs/data.c b/fs/erofs/data.c index 132a27deb2f3..b2c12c5856ac 100644 --- a/fs/erofs/data.c +++ b/fs/erofs/data.c @@ -39,7 +39,7 @@ void *erofs_bread(struct erofs_buf *buf, erofs_off_t offset, bool need_kmap) * However, the data access range must be verified here in advance. */ if (buf->file) { - fpos = index << PAGE_SHIFT; + fpos = (loff_t)index << PAGE_SHIFT; err = rw_verify_area(READ, buf->file, &fpos, PAGE_SIZE); if (err < 0) return ERR_PTR(err); diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c index 8a0b15511931..43bb5a6a9924 100644 --- a/fs/erofs/zdata.c +++ b/fs/erofs/zdata.c @@ -1872,7 +1872,7 @@ static void z_erofs_pcluster_readmore(struct z_erofs_frontend *f, if (cur < PAGE_SIZE) break; - cur = (index << PAGE_SHIFT) - 1; + cur = ((loff_t)index << PAGE_SHIFT) - 1; } } |