Commit 2d8c7edc authored by Gao Xiang's avatar Gao Xiang
Browse files

erofs: unify lcn as u64 for 32-bit platforms 

As sashiko reported [1], `lcn` was typed as `unsigned long` (or
`unsigned int` sometimes), which is only 32 bits wide on 32-bit
platforms, which causes `(lcn << lclusterbits)` to be truncated
at 4 GiB.

In order to consolidate the logic, just use `u64` consistently
around the codebase.

[1] https://sashiko.dev/r/20260420034612.1899973-1-hsiangkao%40linux.alibaba.com



Fixes: 152a333a ("staging: erofs: add compacted compression indexes support")
Signed-off-by: default avatarGao Xiang <hsiangkao@linux.alibaba.com>
parent c99493ce

fs/erofs/zmap.c

+9 −10
Original line number Diff line number Diff line
@@ -10,7 +10,7 @@ 
struct z_erofs_maprecorder {

	struct inode *inode;

	struct erofs_map_blocks *map;

	unsigned long lcn;

	u64 lcn;

	/* compression extent information gathered */

	u8  type, headtype;

	u16 clusterofs;
@@ -20,8 +20,7 @@ struct z_erofs_maprecorder { 
	bool partialref, in_mbox;

};



static int z_erofs_load_full_lcluster(struct z_erofs_maprecorder *m,

				      unsigned long lcn)

static int z_erofs_load_full_lcluster(struct z_erofs_maprecorder *m, u64 lcn)

{

	struct inode *const inode = m->inode;

	struct erofs_inode *const vi = EROFS_I(inode);
@@ -94,7 +93,7 @@ static int get_compacted_la_distance(unsigned int lobits, 
}



static int z_erofs_load_compact_lcluster(struct z_erofs_maprecorder *m,

					 unsigned long lcn, bool lookahead)

					 u64 lcn, bool lookahead)

{

	struct inode *const inode = m->inode;

	struct erofs_inode *const vi = EROFS_I(inode);
@@ -234,7 +233,7 @@ static int z_erofs_load_compact_lcluster(struct z_erofs_maprecorder *m, 
}



static int z_erofs_load_lcluster_from_disk(struct z_erofs_maprecorder *m,

					   unsigned int lcn, bool lookahead)

					   u64 lcn, bool lookahead)

{

	struct erofs_inode *vi = EROFS_I(m->inode);

	int err;
@@ -249,7 +248,7 @@ static int z_erofs_load_lcluster_from_disk(struct z_erofs_maprecorder *m, 
		return err;



	if (m->type >= Z_EROFS_LCLUSTER_TYPE_MAX) {

		erofs_err(m->inode->i_sb, "unknown type %u @ lcn %u of nid %llu",

		erofs_err(m->inode->i_sb, "unknown type %u @ lcn %llu of nid %llu",

			  m->type, lcn, EROFS_I(m->inode)->nid);

		DBG_BUGON(1);

		return -EOPNOTSUPP;
@@ -269,7 +268,7 @@ static int z_erofs_extent_lookback(struct z_erofs_maprecorder *m, 
	const unsigned int lclusterbits = vi->z_lclusterbits;



	while (m->lcn >= lookback_distance) {

		unsigned long lcn = m->lcn - lookback_distance;

		u64 lcn = m->lcn - lookback_distance;

		int err;



		if (!lookback_distance)
@@ -286,7 +285,7 @@ static int z_erofs_extent_lookback(struct z_erofs_maprecorder *m, 
		m->map->m_la = (lcn << lclusterbits) | m->clusterofs;

		return 0;

	}

	erofs_err(sb, "bogus lookback distance %u @ lcn %lu of nid %llu",

	erofs_err(sb, "bogus lookback distance %u @ lcn %llu of nid %llu",

		  lookback_distance, m->lcn, vi->nid);

	DBG_BUGON(1);

	return -EFSCORRUPTED;
@@ -300,7 +299,7 @@ static int z_erofs_get_extent_compressedlen(struct z_erofs_maprecorder *m, 
	struct erofs_inode *vi = EROFS_I(inode);

	bool bigpcl1 = vi->z_advise & Z_EROFS_ADVISE_BIG_PCLUSTER_1;

	bool bigpcl2 = vi->z_advise & Z_EROFS_ADVISE_BIG_PCLUSTER_2;

	unsigned long lcn = m->lcn + 1;

	u64 lcn = m->lcn + 1;

	int err;



	DBG_BUGON(m->type == Z_EROFS_LCLUSTER_TYPE_NONHEAD);
@@ -331,7 +330,7 @@ static int z_erofs_get_extent_compressedlen(struct z_erofs_maprecorder *m, 
		  m->type == Z_EROFS_LCLUSTER_TYPE_NONHEAD);



	if (m->type == Z_EROFS_LCLUSTER_TYPE_NONHEAD && m->delta[0] != 1) {

		erofs_err(sb, "bogus CBLKCNT @ lcn %lu of nid %llu", lcn, vi->nid);

		erofs_err(sb, "bogus CBLKCNT @ lcn %llu of nid %llu", lcn, vi->nid);

		DBG_BUGON(1);

		return -EFSCORRUPTED;

	}