linux/block/partitions/msdos.c

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 14:07:57 +00:00
// SPDX-License-Identifier: GPL-2.0
/*
* fs/partitions/msdos.c
*
* Code extracted from drivers/block/genhd.c
* Copyright (C) 1991-1998 Linus Torvalds
*
* Thanks to Branko Lankester, lankeste@fwi.uva.nl, who found a bug
* in the early extended-partition checks and added DM partitions
*
* Support for DiskManager v6.0x added by Mark Lord,
* with information provided by OnTrack. This now works for linux fdisk
* and LILO, as well as loadlin and bootln. Note that disks other than
* /dev/hda *must* have a "DOS" type 0x51 partition in the first slot (hda1).
*
* More flexible handling of extended partitions - aeb, 950831
*
* Check partition table on IDE disks for common CHS translations
*
* Re-organised Feb 1998 Russell King
*/
#include <linux/msdos_fs.h>
#include "check.h"
#include "msdos.h"
#include "efi.h"
#include "aix.h"
/*
* Many architectures don't like unaligned accesses, while
* the nr_sects and start_sect partition table entries are
* at a 2 (mod 4) address.
*/
#include <asm/unaligned.h>
#define SYS_IND(p) get_unaligned(&p->sys_ind)
static inline sector_t nr_sects(struct partition *p)
{
return (sector_t)get_unaligned_le32(&p->nr_sects);
}
static inline sector_t start_sect(struct partition *p)
{
return (sector_t)get_unaligned_le32(&p->start_sect);
}
static inline int is_extended_partition(struct partition *p)
{
return (SYS_IND(p) == DOS_EXTENDED_PARTITION ||
SYS_IND(p) == WIN98_EXTENDED_PARTITION ||
SYS_IND(p) == LINUX_EXTENDED_PARTITION);
}
#define MSDOS_LABEL_MAGIC1 0x55
#define MSDOS_LABEL_MAGIC2 0xAA
static inline int
msdos_magic_present(unsigned char *p)
{
return (p[0] == MSDOS_LABEL_MAGIC1 && p[1] == MSDOS_LABEL_MAGIC2);
}
/* Value is EBCDIC 'IBMA' */
#define AIX_LABEL_MAGIC1 0xC9
#define AIX_LABEL_MAGIC2 0xC2
#define AIX_LABEL_MAGIC3 0xD4
#define AIX_LABEL_MAGIC4 0xC1
static int aix_magic_present(struct parsed_partitions *state, unsigned char *p)
{
struct partition *pt = (struct partition *) (p + 0x1be);
Sector sect;
unsigned char *d;
int slot, ret = 0;
if (!(p[0] == AIX_LABEL_MAGIC1 &&
p[1] == AIX_LABEL_MAGIC2 &&
p[2] == AIX_LABEL_MAGIC3 &&
p[3] == AIX_LABEL_MAGIC4))
return 0;
/* Assume the partition table is valid if Linux partitions exists */
for (slot = 1; slot <= 4; slot++, pt++) {
if (pt->sys_ind == LINUX_SWAP_PARTITION ||
pt->sys_ind == LINUX_RAID_PARTITION ||
pt->sys_ind == LINUX_DATA_PARTITION ||
pt->sys_ind == LINUX_LVM_PARTITION ||
is_extended_partition(pt))
return 0;
}
d = read_part_sector(state, 7, &sect);
if (d) {
if (d[0] == '_' && d[1] == 'L' && d[2] == 'V' && d[3] == 'M')
ret = 1;
put_dev_sector(sect);
}
return ret;
}
static void set_info(struct parsed_partitions *state, int slot,
u32 disksig)
{
struct partition_meta_info *info = &state->parts[slot].info;
snprintf(info->uuid, sizeof(info->uuid), "%08x-%02x", disksig,
slot);
info->volname[0] = 0;
state->parts[slot].has_info = true;
}
/*
* Create devices for each logical partition in an extended partition.
* The logical partitions form a linked list, with each entry being
* a partition table with two entries. The first entry
* is the real data partition (with a start relative to the partition
* table start). The second is a pointer to the next logical partition
* (with a start relative to the entire extended partition).
* We do not create a Linux partition for the partition tables, but
* only for the actual data partitions.
*/
static void parse_extended(struct parsed_partitions *state,
sector_t first_sector, sector_t first_size,
u32 disksig)
{
struct partition *p;
Sector sect;
unsigned char *data;
sector_t this_sector, this_size;
sector_t sector_size = bdev_logical_block_size(state->bdev) / 512;
int loopct = 0; /* number of links followed
without finding a data partition */
int i;
this_sector = first_sector;
this_size = first_size;
while (1) {
if (++loopct > 100)
return;
if (state->next == state->limit)
return;
data = read_part_sector(state, this_sector, &sect);
if (!data)
return;
if (!msdos_magic_present(data + 510))
goto done;
p = (struct partition *) (data + 0x1be);
/*
* Usually, the first entry is the real data partition,
* the 2nd entry is the next extended partition, or empty,
* and the 3rd and 4th entries are unused.
* However, DRDOS sometimes has the extended partition as
* the first entry (when the data partition is empty),
* and OS/2 seems to use all four entries.
*/
/*
* First process the data partition(s)
*/
for (i = 0; i < 4; i++, p++) {
sector_t offs, size, next;
if (!nr_sects(p) || is_extended_partition(p))
continue;
/* Check the 3rd and 4th entries -
these sometimes contain random garbage */
offs = start_sect(p)*sector_size;
size = nr_sects(p)*sector_size;
next = this_sector + offs;
if (i >= 2) {
if (offs + size > this_size)
continue;
if (next < first_sector)
continue;
if (next + size > first_sector + first_size)
continue;
}
put_partition(state, state->next, next, size);
set_info(state, state->next, disksig);
if (SYS_IND(p) == LINUX_RAID_PARTITION)
state->parts[state->next].flags = ADDPART_FLAG_RAID;
loopct = 0;
if (++state->next == state->limit)
goto done;
}
/*
* Next, process the (first) extended partition, if present.
* (So far, there seems to be no reason to make
* parse_extended() recursive and allow a tree
* of extended partitions.)
* It should be a link to the next logical partition.
*/
p -= 4;
for (i = 0; i < 4; i++, p++)
if (nr_sects(p) && is_extended_partition(p))
break;
if (i == 4)
goto done; /* nothing left to do */
this_sector = first_sector + start_sect(p) * sector_size;
this_size = nr_sects(p) * sector_size;
put_dev_sector(sect);
}
done:
put_dev_sector(sect);
}
/* james@bpgc.com: Solaris has a nasty indicator: 0x82 which also
indicates linux swap. Be careful before believing this is Solaris. */
static void parse_solaris_x86(struct parsed_partitions *state,
sector_t offset, sector_t size, int origin)
{
#ifdef CONFIG_SOLARIS_X86_PARTITION
Sector sect;
struct solaris_x86_vtoc *v;
int i;
short max_nparts;
v = read_part_sector(state, offset + 1, &sect);
if (!v)
return;
if (le32_to_cpu(v->v_sanity) != SOLARIS_X86_VTOC_SANE) {
put_dev_sector(sect);
return;
}
{
char tmp[1 + BDEVNAME_SIZE + 10 + 11 + 1];
snprintf(tmp, sizeof(tmp), " %s%d: <solaris:", state->name, origin);
strlcat(state->pp_buf, tmp, PAGE_SIZE);
}
if (le32_to_cpu(v->v_version) != 1) {
char tmp[64];
snprintf(tmp, sizeof(tmp), " cannot handle version %d vtoc>\n",
le32_to_cpu(v->v_version));
strlcat(state->pp_buf, tmp, PAGE_SIZE);
put_dev_sector(sect);
return;
}
/* Ensure we can handle previous case of VTOC with 8 entries gracefully */
max_nparts = le16_to_cpu(v->v_nparts) > 8 ? SOLARIS_X86_NUMSLICE : 8;
for (i = 0; i < max_nparts && state->next < state->limit; i++) {
struct solaris_x86_slice *s = &v->v_slice[i];
char tmp[3 + 10 + 1 + 1];
if (s->s_size == 0)
continue;
snprintf(tmp, sizeof(tmp), " [s%d]", i);
strlcat(state->pp_buf, tmp, PAGE_SIZE);
/* solaris partitions are relative to current MS-DOS
* one; must add the offset of the current partition */
put_partition(state, state->next++,
le32_to_cpu(s->s_start)+offset,
le32_to_cpu(s->s_size));
}
put_dev_sector(sect);
strlcat(state->pp_buf, " >\n", PAGE_SIZE);
#endif
}
#if defined(CONFIG_BSD_DISKLABEL)
/*
* Create devices for BSD partitions listed in a disklabel, under a
* dos-like partition. See parse_extended() for more information.
*/
static void parse_bsd(struct parsed_partitions *state,
sector_t offset, sector_t size, int origin, char *flavour,
int max_partitions)
{
Sector sect;
struct bsd_disklabel *l;
struct bsd_partition *p;
char tmp[64];
l = read_part_sector(state, offset + 1, &sect);
if (!l)
return;
if (le32_to_cpu(l->d_magic) != BSD_DISKMAGIC) {
put_dev_sector(sect);
return;
}
snprintf(tmp, sizeof(tmp), " %s%d: <%s:", state->name, origin, flavour);
strlcat(state->pp_buf, tmp, PAGE_SIZE);
if (le16_to_cpu(l->d_npartitions) < max_partitions)
max_partitions = le16_to_cpu(l->d_npartitions);
for (p = l->d_partitions; p - l->d_partitions < max_partitions; p++) {
sector_t bsd_start, bsd_size;
if (state->next == state->limit)
break;
if (p->p_fstype == BSD_FS_UNUSED)
continue;
bsd_start = le32_to_cpu(p->p_offset);
bsd_size = le32_to_cpu(p->p_size);
if (memcmp(flavour, "bsd\0", 4) == 0)
bsd_start += offset;
if (offset == bsd_start && size == bsd_size)
/* full parent partition, we have it already */
continue;
if (offset > bsd_start || offset+size < bsd_start+bsd_size) {
strlcat(state->pp_buf, "bad subpartition - ignored\n", PAGE_SIZE);
continue;
}
put_partition(state, state->next++, bsd_start, bsd_size);
}
put_dev_sector(sect);
if (le16_to_cpu(l->d_npartitions) > max_partitions) {
snprintf(tmp, sizeof(tmp), " (ignored %d more)",
le16_to_cpu(l->d_npartitions) - max_partitions);
strlcat(state->pp_buf, tmp, PAGE_SIZE);
}
strlcat(state->pp_buf, " >\n", PAGE_SIZE);
}
#endif
static void parse_freebsd(struct parsed_partitions *state,
sector_t offset, sector_t size, int origin)
{
#ifdef CONFIG_BSD_DISKLABEL
parse_bsd(state, offset, size, origin, "bsd", BSD_MAXPARTITIONS);
#endif
}
static void parse_netbsd(struct parsed_partitions *state,
sector_t offset, sector_t size, int origin)
{
#ifdef CONFIG_BSD_DISKLABEL
parse_bsd(state, offset, size, origin, "netbsd", BSD_MAXPARTITIONS);
#endif
}
static void parse_openbsd(struct parsed_partitions *state,
sector_t offset, sector_t size, int origin)
{
#ifdef CONFIG_BSD_DISKLABEL
parse_bsd(state, offset, size, origin, "openbsd",
OPENBSD_MAXPARTITIONS);
#endif
}
/*
* Create devices for Unixware partitions listed in a disklabel, under a
* dos-like partition. See parse_extended() for more information.
*/
static void parse_unixware(struct parsed_partitions *state,
sector_t offset, sector_t size, int origin)
{
#ifdef CONFIG_UNIXWARE_DISKLABEL
Sector sect;
struct unixware_disklabel *l;
struct unixware_slice *p;
l = read_part_sector(state, offset + 29, &sect);
if (!l)
return;
if (le32_to_cpu(l->d_magic) != UNIXWARE_DISKMAGIC ||
le32_to_cpu(l->vtoc.v_magic) != UNIXWARE_DISKMAGIC2) {
put_dev_sector(sect);
return;
}
{
char tmp[1 + BDEVNAME_SIZE + 10 + 12 + 1];
snprintf(tmp, sizeof(tmp), " %s%d: <unixware:", state->name, origin);
strlcat(state->pp_buf, tmp, PAGE_SIZE);
}
p = &l->vtoc.v_slice[1];
/* I omit the 0th slice as it is the same as whole disk. */
while (p - &l->vtoc.v_slice[0] < UNIXWARE_NUMSLICE) {
if (state->next == state->limit)
break;
if (p->s_label != UNIXWARE_FS_UNUSED)
put_partition(state, state->next++,
le32_to_cpu(p->start_sect),
le32_to_cpu(p->nr_sects));
p++;
}
put_dev_sector(sect);
strlcat(state->pp_buf, " >\n", PAGE_SIZE);
#endif
}
/*
* Minix 2.0.0/2.0.2 subpartition support.
* Anand Krishnamurthy <anandk@wiproge.med.ge.com>
* Rajeev V. Pillai <rajeevvp@yahoo.com>
*/
static void parse_minix(struct parsed_partitions *state,
sector_t offset, sector_t size, int origin)
{
#ifdef CONFIG_MINIX_SUBPARTITION
Sector sect;
unsigned char *data;
struct partition *p;
int i;
data = read_part_sector(state, offset, &sect);
if (!data)
return;
p = (struct partition *)(data + 0x1be);
/* The first sector of a Minix partition can have either
* a secondary MBR describing its subpartitions, or
* the normal boot sector. */
if (msdos_magic_present(data + 510) &&
SYS_IND(p) == MINIX_PARTITION) { /* subpartition table present */
char tmp[1 + BDEVNAME_SIZE + 10 + 9 + 1];
snprintf(tmp, sizeof(tmp), " %s%d: <minix:", state->name, origin);
strlcat(state->pp_buf, tmp, PAGE_SIZE);
for (i = 0; i < MINIX_NR_SUBPARTITIONS; i++, p++) {
if (state->next == state->limit)
break;
/* add each partition in use */
if (SYS_IND(p) == MINIX_PARTITION)
put_partition(state, state->next++,
start_sect(p), nr_sects(p));
}
strlcat(state->pp_buf, " >\n", PAGE_SIZE);
}
put_dev_sector(sect);
#endif /* CONFIG_MINIX_SUBPARTITION */
}
static struct {
unsigned char id;
void (*parse)(struct parsed_partitions *, sector_t, sector_t, int);
} subtypes[] = {
{FREEBSD_PARTITION, parse_freebsd},
{NETBSD_PARTITION, parse_netbsd},
{OPENBSD_PARTITION, parse_openbsd},
{MINIX_PARTITION, parse_minix},
{UNIXWARE_PARTITION, parse_unixware},
{SOLARIS_X86_PARTITION, parse_solaris_x86},
{NEW_SOLARIS_X86_PARTITION, parse_solaris_x86},
{0, NULL},
};
int msdos_partition(struct parsed_partitions *state)
{
sector_t sector_size = bdev_logical_block_size(state->bdev) / 512;
Sector sect;
unsigned char *data;
struct partition *p;
struct fat_boot_sector *fb;
int slot;
u32 disksig;
data = read_part_sector(state, 0, &sect);
if (!data)
return -1;
/*
* Note order! (some AIX disks, e.g. unbootable kind,
* have no MSDOS 55aa)
*/
if (aix_magic_present(state, data)) {
put_dev_sector(sect);
#ifdef CONFIG_AIX_PARTITION
return aix_partition(state);
#else
strlcat(state->pp_buf, " [AIX]", PAGE_SIZE);
return 0;
#endif
}
if (!msdos_magic_present(data + 510)) {
put_dev_sector(sect);
return 0;
}
/*
* Now that the 55aa signature is present, this is probably
* either the boot sector of a FAT filesystem or a DOS-type
* partition table. Reject this in case the boot indicator
* is not 0 or 0x80.
*/
p = (struct partition *) (data + 0x1be);
for (slot = 1; slot <= 4; slot++, p++) {
if (p->boot_ind != 0 && p->boot_ind != 0x80) {
/*
* Even without a valid boot inidicator value
* its still possible this is valid FAT filesystem
* without a partition table.
*/
fb = (struct fat_boot_sector *) data;
if (slot == 1 && fb->reserved && fb->fats
&& fat_valid_media(fb->media)) {
strlcat(state->pp_buf, "\n", PAGE_SIZE);
put_dev_sector(sect);
return 1;
} else {
put_dev_sector(sect);
return 0;
}
}
}
#ifdef CONFIG_EFI_PARTITION
p = (struct partition *) (data + 0x1be);
for (slot = 1 ; slot <= 4 ; slot++, p++) {
/* If this is an EFI GPT disk, msdos should ignore it. */
if (SYS_IND(p) == EFI_PMBR_OSTYPE_EFI_GPT) {
put_dev_sector(sect);
return 0;
}
}
#endif
p = (struct partition *) (data + 0x1be);
disksig = le32_to_cpup((__le32 *)(data + 0x1b8));
/*
* Look for partitions in two passes:
* First find the primary and DOS-type extended partitions.
* On the second pass look inside *BSD, Unixware and Solaris partitions.
*/
state->next = 5;
for (slot = 1 ; slot <= 4 ; slot++, p++) {
sector_t start = start_sect(p)*sector_size;
sector_t size = nr_sects(p)*sector_size;
if (!size)
continue;
if (is_extended_partition(p)) {
/*
* prevent someone doing mkfs or mkswap on an
* extended partition, but leave room for LILO
* FIXME: this uses one logical sector for > 512b
* sector, although it may not be enough/proper.
*/
sector_t n = 2;
n = min(size, max(sector_size, n));
put_partition(state, slot, start, n);
strlcat(state->pp_buf, " <", PAGE_SIZE);
parse_extended(state, start, size, disksig);
strlcat(state->pp_buf, " >", PAGE_SIZE);
continue;
}
put_partition(state, slot, start, size);
set_info(state, slot, disksig);
if (SYS_IND(p) == LINUX_RAID_PARTITION)
state->parts[slot].flags = ADDPART_FLAG_RAID;
if (SYS_IND(p) == DM6_PARTITION)
strlcat(state->pp_buf, "[DM]", PAGE_SIZE);
if (SYS_IND(p) == EZD_PARTITION)
strlcat(state->pp_buf, "[EZD]", PAGE_SIZE);
}
strlcat(state->pp_buf, "\n", PAGE_SIZE);
/* second pass - output for each on a separate line */
p = (struct partition *) (0x1be + data);
for (slot = 1 ; slot <= 4 ; slot++, p++) {
unsigned char id = SYS_IND(p);
int n;
if (!nr_sects(p))
continue;
for (n = 0; subtypes[n].parse && id != subtypes[n].id; n++)
;
if (!subtypes[n].parse)
continue;
subtypes[n].parse(state, start_sect(p) * sector_size,
nr_sects(p) * sector_size, slot);
}
put_dev_sector(sect);
return 1;
}