bridge: fix a possible use after free
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / fs / partitions / ibm.c
blobd513a07f44bb54805de9adf7171c0991aa4ab309
1 /*
2 * File...........: linux/fs/partitions/ibm.c
3 * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
4 * Volker Sameske <sameske@de.ibm.com>
5 * Bugreports.to..: <Linux390@de.ibm.com>
6 * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999,2000
7 */
9 #include <linux/buffer_head.h>
10 #include <linux/hdreg.h>
11 #include <linux/slab.h>
12 #include <asm/dasd.h>
13 #include <asm/ebcdic.h>
14 #include <asm/uaccess.h>
15 #include <asm/vtoc.h>
17 #include "check.h"
18 #include "ibm.h"
21 * compute the block number from a
22 * cyl-cyl-head-head structure
24 static sector_t
25 cchh2blk (struct vtoc_cchh *ptr, struct hd_geometry *geo) {
27 sector_t cyl;
28 __u16 head;
30 /*decode cylinder and heads for large volumes */
31 cyl = ptr->hh & 0xFFF0;
32 cyl <<= 12;
33 cyl |= ptr->cc;
34 head = ptr->hh & 0x000F;
35 return cyl * geo->heads * geo->sectors +
36 head * geo->sectors;
40 * compute the block number from a
41 * cyl-cyl-head-head-block structure
43 static sector_t
44 cchhb2blk (struct vtoc_cchhb *ptr, struct hd_geometry *geo) {
46 sector_t cyl;
47 __u16 head;
49 /*decode cylinder and heads for large volumes */
50 cyl = ptr->hh & 0xFFF0;
51 cyl <<= 12;
52 cyl |= ptr->cc;
53 head = ptr->hh & 0x000F;
54 return cyl * geo->heads * geo->sectors +
55 head * geo->sectors +
56 ptr->b;
61 int ibm_partition(struct parsed_partitions *state)
63 struct block_device *bdev = state->bdev;
64 int blocksize, res;
65 loff_t i_size, offset, size, fmt_size;
66 dasd_information2_t *info;
67 struct hd_geometry *geo;
68 char type[5] = {0,};
69 char name[7] = {0,};
70 union label_t {
71 struct vtoc_volume_label_cdl vol;
72 struct vtoc_volume_label_ldl lnx;
73 struct vtoc_cms_label cms;
74 } *label;
75 unsigned char *data;
76 Sector sect;
77 sector_t labelsect;
78 char tmp[64];
80 res = 0;
81 blocksize = bdev_logical_block_size(bdev);
82 if (blocksize <= 0)
83 goto out_exit;
84 i_size = i_size_read(bdev->bd_inode);
85 if (i_size == 0)
86 goto out_exit;
88 info = kmalloc(sizeof(dasd_information2_t), GFP_KERNEL);
89 if (info == NULL)
90 goto out_exit;
91 geo = kmalloc(sizeof(struct hd_geometry), GFP_KERNEL);
92 if (geo == NULL)
93 goto out_nogeo;
94 label = kmalloc(sizeof(union label_t), GFP_KERNEL);
95 if (label == NULL)
96 goto out_nolab;
98 if (ioctl_by_bdev(bdev, BIODASDINFO2, (unsigned long)info) != 0 ||
99 ioctl_by_bdev(bdev, HDIO_GETGEO, (unsigned long)geo) != 0)
100 goto out_freeall;
103 * Special case for FBA disks: label sector does not depend on
104 * blocksize.
106 if ((info->cu_type == 0x6310 && info->dev_type == 0x9336) ||
107 (info->cu_type == 0x3880 && info->dev_type == 0x3370))
108 labelsect = info->label_block;
109 else
110 labelsect = info->label_block * (blocksize >> 9);
113 * Get volume label, extract name and type.
115 data = read_part_sector(state, labelsect, &sect);
116 if (data == NULL)
117 goto out_readerr;
119 memcpy(label, data, sizeof(union label_t));
120 put_dev_sector(sect);
122 if ((!info->FBA_layout) && (!strcmp(info->type, "ECKD"))) {
123 strncpy(type, label->vol.vollbl, 4);
124 strncpy(name, label->vol.volid, 6);
125 } else {
126 strncpy(type, label->lnx.vollbl, 4);
127 strncpy(name, label->lnx.volid, 6);
129 EBCASC(type, 4);
130 EBCASC(name, 6);
132 res = 1;
135 * Three different formats: LDL, CDL and unformated disk
137 * identified by info->format
139 * unformated disks we do not have to care about
141 if (info->format == DASD_FORMAT_LDL) {
142 if (strncmp(type, "CMS1", 4) == 0) {
144 * VM style CMS1 labeled disk
146 blocksize = label->cms.block_size;
147 if (label->cms.disk_offset != 0) {
148 snprintf(tmp, sizeof(tmp), "CMS1/%8s(MDSK):", name);
149 strlcat(state->pp_buf, tmp, PAGE_SIZE);
150 /* disk is reserved minidisk */
151 offset = label->cms.disk_offset;
152 size = (label->cms.block_count - 1)
153 * (blocksize >> 9);
154 } else {
155 snprintf(tmp, sizeof(tmp), "CMS1/%8s:", name);
156 strlcat(state->pp_buf, tmp, PAGE_SIZE);
157 offset = (info->label_block + 1);
158 size = label->cms.block_count
159 * (blocksize >> 9);
161 put_partition(state, 1, offset*(blocksize >> 9),
162 size-offset*(blocksize >> 9));
163 } else {
164 if (strncmp(type, "LNX1", 4) == 0) {
165 snprintf(tmp, sizeof(tmp), "LNX1/%8s:", name);
166 strlcat(state->pp_buf, tmp, PAGE_SIZE);
167 if (label->lnx.ldl_version == 0xf2) {
168 fmt_size = label->lnx.formatted_blocks
169 * (blocksize >> 9);
170 } else if (!strcmp(info->type, "ECKD")) {
171 /* formated w/o large volume support */
172 fmt_size = geo->cylinders * geo->heads
173 * geo->sectors * (blocksize >> 9);
174 } else {
175 /* old label and no usable disk geometry
176 * (e.g. DIAG) */
177 fmt_size = i_size >> 9;
179 size = i_size >> 9;
180 if (fmt_size < size)
181 size = fmt_size;
182 offset = (info->label_block + 1);
183 } else {
184 /* unlabeled disk */
185 strlcat(state->pp_buf, "(nonl)", PAGE_SIZE);
186 size = i_size >> 9;
187 offset = (info->label_block + 1);
189 put_partition(state, 1, offset*(blocksize >> 9),
190 size-offset*(blocksize >> 9));
192 } else if (info->format == DASD_FORMAT_CDL) {
194 * New style CDL formatted disk
196 sector_t blk;
197 int counter;
200 * check if VOL1 label is available
201 * if not, something is wrong, skipping partition detection
203 if (strncmp(type, "VOL1", 4) == 0) {
204 snprintf(tmp, sizeof(tmp), "VOL1/%8s:", name);
205 strlcat(state->pp_buf, tmp, PAGE_SIZE);
207 * get block number and read then go through format1
208 * labels
210 blk = cchhb2blk(&label->vol.vtoc, geo) + 1;
211 counter = 0;
212 data = read_part_sector(state, blk * (blocksize/512),
213 &sect);
214 while (data != NULL) {
215 struct vtoc_format1_label f1;
217 memcpy(&f1, data,
218 sizeof(struct vtoc_format1_label));
219 put_dev_sector(sect);
221 /* skip FMT4 / FMT5 / FMT7 labels */
222 if (f1.DS1FMTID == _ascebc['4']
223 || f1.DS1FMTID == _ascebc['5']
224 || f1.DS1FMTID == _ascebc['7']
225 || f1.DS1FMTID == _ascebc['9']) {
226 blk++;
227 data = read_part_sector(state,
228 blk * (blocksize/512), &sect);
229 continue;
232 /* only FMT1 and 8 labels valid at this point */
233 if (f1.DS1FMTID != _ascebc['1'] &&
234 f1.DS1FMTID != _ascebc['8'])
235 break;
237 /* OK, we got valid partition data */
238 offset = cchh2blk(&f1.DS1EXT1.llimit, geo);
239 size = cchh2blk(&f1.DS1EXT1.ulimit, geo) -
240 offset + geo->sectors;
241 if (counter >= state->limit)
242 break;
243 put_partition(state, counter + 1,
244 offset * (blocksize >> 9),
245 size * (blocksize >> 9));
246 counter++;
247 blk++;
248 data = read_part_sector(state,
249 blk * (blocksize/512), &sect);
252 if (!data)
253 /* Are we not supposed to report this ? */
254 goto out_readerr;
255 } else
256 printk(KERN_WARNING "Warning, expected Label VOL1 not "
257 "found, treating as CDL formated Disk");
261 strlcat(state->pp_buf, "\n", PAGE_SIZE);
262 goto out_freeall;
265 out_readerr:
266 res = -1;
267 out_freeall:
268 kfree(label);
269 out_nolab:
270 kfree(geo);
271 out_nogeo:
272 kfree(info);
273 out_exit:
274 return res;