Commit d63b77f4 authored by Sage Weil's avatar Sage Weil Committed by Alex Elder
Browse files

libceph: check for invalid mapping 



If we encounter an invalid (e.g., zeroed) mapping, return an error
and avoid a divide by zero.

Signed-off-by: default avatarSage Weil <sage@inktank.com>
Reviewed-by: default avatarAlex Elder <elder@inktank.com>
parent b905a7f8

include/linux/ceph/osd_client.h

+1 −1
Original line number Diff line number Diff line
@@ -207,7 +207,7 @@ extern void ceph_osdc_handle_reply(struct ceph_osd_client *osdc, 
extern void ceph_osdc_handle_map(struct ceph_osd_client *osdc,

				 struct ceph_msg *msg);



extern void ceph_calc_raw_layout(struct ceph_osd_client *osdc,

extern int ceph_calc_raw_layout(struct ceph_osd_client *osdc,

			struct ceph_file_layout *layout,

			u64 snapid,

			u64 off, u64 *plen, u64 *bno,

include/linux/ceph/osdmap.h

+3 −3
Original line number Diff line number Diff line
@@ -109,7 +109,7 @@ extern struct ceph_osdmap *osdmap_apply_incremental(void **p, void *end, 
extern void ceph_osdmap_destroy(struct ceph_osdmap *map);



/* calculate mapping of a file extent to an object */

extern void ceph_calc_file_object_mapping(struct ceph_file_layout *layout,

extern int ceph_calc_file_object_mapping(struct ceph_file_layout *layout,

					 u64 off, u64 *plen,

					 u64 *bno, u64 *oxoff, u64 *oxlen);

net/ceph/osd_client.c

+20 −12
Original line number Diff line number Diff line
@@ -52,7 +52,7 @@ static int op_has_extent(int op) 
		op == CEPH_OSD_OP_WRITE);

}



void ceph_calc_raw_layout(struct ceph_osd_client *osdc,

int ceph_calc_raw_layout(struct ceph_osd_client *osdc,

			struct ceph_file_layout *layout,

			u64 snapid,

			u64 off, u64 *plen, u64 *bno,
@@ -62,12 +62,15 @@ void ceph_calc_raw_layout(struct ceph_osd_client *osdc, 
	struct ceph_osd_request_head *reqhead = req->r_request->front.iov_base;

	u64 orig_len = *plen;

	u64 objoff, objlen;    /* extent in object */

	int r;



	reqhead->snapid = cpu_to_le64(snapid);



	/* object extent? */

	ceph_calc_file_object_mapping(layout, off, plen, bno,

	r = ceph_calc_file_object_mapping(layout, off, plen, bno,

					  &objoff, &objlen);

	if (r < 0)

		return r;

	if (*plen < orig_len)

		dout(" skipping last %llu, final file extent %llu~%llu\n",

		     orig_len - *plen, off, *plen);
@@ -83,7 +86,7 @@ void ceph_calc_raw_layout(struct ceph_osd_client *osdc, 


	dout("calc_layout bno=%llx %llu~%llu (%d pages)\n",

	     *bno, objoff, objlen, req->r_num_pages);



	return 0;

}

EXPORT_SYMBOL(ceph_calc_raw_layout);
@@ -112,7 +115,7 @@ EXPORT_SYMBOL(ceph_calc_raw_layout); 
 *

 * fill osd op in request message.

 */

static void calc_layout(struct ceph_osd_client *osdc,

static int calc_layout(struct ceph_osd_client *osdc,

		       struct ceph_vino vino,

		       struct ceph_file_layout *layout,

		       u64 off, u64 *plen,
@@ -120,12 +123,17 @@ static void calc_layout(struct ceph_osd_client *osdc, 
		       struct ceph_osd_req_op *op)

{

	u64 bno;

	int r;



	ceph_calc_raw_layout(osdc, layout, vino.snap, off,

	r = ceph_calc_raw_layout(osdc, layout, vino.snap, off,

				 plen, &bno, req, op);

	if (r < 0)

		return r;



	snprintf(req->r_oid, sizeof(req->r_oid), "%llx.%08llx", vino.ino, bno);

	req->r_oid_len = strlen(req->r_oid);



	return r;

}



/*

net/ceph/osdmap.c

+16 −2
Original line number Diff line number Diff line
@@ -984,7 +984,7 @@ struct ceph_osdmap *osdmap_apply_incremental(void **p, void *end, 
 * for now, we write only a single su, until we can

 * pass a stride back to the caller.

 */

void ceph_calc_file_object_mapping(struct ceph_file_layout *layout,

int ceph_calc_file_object_mapping(struct ceph_file_layout *layout,

				   u64 off, u64 *plen,

				   u64 *ono,

				   u64 *oxoff, u64 *oxlen)
@@ -998,11 +998,17 @@ void ceph_calc_file_object_mapping(struct ceph_file_layout *layout, 


	dout("mapping %llu~%llu  osize %u fl_su %u\n", off, *plen,

	     osize, su);

	if (su == 0 || sc == 0)

		goto invalid;

	su_per_object = osize / su;

	if (su_per_object == 0)

		goto invalid;

	dout("osize %u / su %u = su_per_object %u\n", osize, su,

	     su_per_object);



	BUG_ON((su & ~PAGE_MASK) != 0);

	if ((su & ~PAGE_MASK) != 0)

		goto invalid;



	/* bl = *off / su; */

	t = off;

	do_div(t, su);
@@ -1030,6 +1036,14 @@ void ceph_calc_file_object_mapping(struct ceph_file_layout *layout, 
	*plen = *oxlen;



	dout(" obj extent %llu~%llu\n", *oxoff, *oxlen);

	return 0;



invalid:

	dout(" invalid layout\n");

	*ono = 0;

	*oxoff = 0;

	*oxlen = 0;

	return -EINVAL;

}

EXPORT_SYMBOL(ceph_calc_file_object_mapping);