linux-stable/fs/hfsplus/bitmap.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
/*
* linux/fs/hfsplus/bitmap.c
*
* Copyright (C) 2001
* Brad Boyer (flar@allandria.com)
* (C) 2003 Ardis Technologies <roman@ardistech.com>
*
* Handling of allocation file
*/
#include <linux/pagemap.h>
#include "hfsplus_fs.h"
#include "hfsplus_raw.h"
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 12:29:47 +00:00
#define PAGE_CACHE_BITS (PAGE_SIZE * 8)
int hfsplus_block_allocate(struct super_block *sb, u32 size,
u32 offset, u32 *max)
{
struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
struct page *page;
struct address_space *mapping;
__be32 *pptr, *curr, *end;
u32 mask, start, len, n;
__be32 val;
int i;
len = *max;
if (!len)
return size;
hfs_dbg(BITMAP, "block_allocate: %u,%u,%u\n", size, offset, len);
mutex_lock(&sbi->alloc_mutex);
mapping = sbi->alloc_file->i_mapping;
page = read_mapping_page(mapping, offset / PAGE_CACHE_BITS, NULL);
hfsplus: check read_mapping_page() return value While testing more corrupted images with hfsplus, i came across one which triggered the following bug: [15840.675016] BUG: unable to handle kernel paging request at fffffffb [15840.675016] IP: [<c0116a4f>] kmap+0x15/0x56 [15840.675016] *pde = 00008067 *pte = 00000000 [15840.675016] Oops: 0000 [#1] PREEMPT DEBUG_PAGEALLOC [15840.675016] Modules linked in: [15840.675016] [15840.675016] Pid: 11575, comm: ln Not tainted (2.6.27-rc4-00123-gd3ee1b4-dirty #29) [15840.675016] EIP: 0060:[<c0116a4f>] EFLAGS: 00010202 CPU: 0 [15840.675016] EIP is at kmap+0x15/0x56 [15840.675016] EAX: 00000246 EBX: fffffffb ECX: 00000000 EDX: cab919c0 [15840.675016] ESI: 000007dd EDI: cab0bcf4 EBP: cab0bc98 ESP: cab0bc94 [15840.675016] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 0068 [15840.675016] Process ln (pid: 11575, ti=cab0b000 task=cab919c0 task.ti=cab0b000) [15840.675016] Stack: 00000000 cab0bcdc c0231cfb 00000000 cab0bce0 00000800 ca9290c0 fffffffb [15840.675016] cab145d0 cab919c0 cab15998 22222222 22222222 22222222 00000001 cab15960 [15840.675016] 000007dd cab0bcf4 cab0bd04 c022cb3a cab0bcf4 cab15a6c ca9290c0 00000000 [15840.675016] Call Trace: [15840.675016] [<c0231cfb>] ? hfsplus_block_allocate+0x6f/0x2d3 [15840.675016] [<c022cb3a>] ? hfsplus_file_extend+0xc4/0x1db [15840.675016] [<c022ce41>] ? hfsplus_get_block+0x8c/0x19d [15840.675016] [<c06adde4>] ? sub_preempt_count+0x9d/0xab [15840.675016] [<c019ece6>] ? __block_prepare_write+0x147/0x311 [15840.675016] [<c0161934>] ? __grab_cache_page+0x52/0x73 [15840.675016] [<c019ef4f>] ? block_write_begin+0x79/0xd5 [15840.675016] [<c022cdb5>] ? hfsplus_get_block+0x0/0x19d [15840.675016] [<c019f22a>] ? cont_write_begin+0x27f/0x2af [15840.675016] [<c022cdb5>] ? hfsplus_get_block+0x0/0x19d [15840.675016] [<c0139ebe>] ? tick_program_event+0x28/0x4c [15840.675016] [<c013bd35>] ? trace_hardirqs_off+0xb/0xd [15840.675016] [<c022b723>] ? hfsplus_write_begin+0x2d/0x32 [15840.675016] [<c022cdb5>] ? hfsplus_get_block+0x0/0x19d [15840.675016] [<c0161988>] ? pagecache_write_begin+0x33/0x107 [15840.675016] [<c01879e5>] ? __page_symlink+0x3c/0xae [15840.675016] [<c019ad34>] ? __mark_inode_dirty+0x12f/0x137 [15840.675016] [<c0187a70>] ? page_symlink+0x19/0x1e [15840.675016] [<c022e6eb>] ? hfsplus_symlink+0x41/0xa6 [15840.675016] [<c01886a9>] ? vfs_symlink+0x99/0x101 [15840.675016] [<c018a2f6>] ? sys_symlinkat+0x6b/0xad [15840.675016] [<c018a348>] ? sys_symlink+0x10/0x12 [15840.675016] [<c01038bd>] ? sysenter_do_call+0x12/0x31 [15840.675016] ======================= [15840.675016] Code: 00 00 75 10 83 3d 88 2f ec c0 02 75 07 89 d0 e8 12 56 05 00 5d c3 55 ba 06 00 00 00 89 e5 53 89 c3 b8 3d eb 7e c0 e8 16 74 00 00 <8b> 03 c1 e8 1e 69 c0 d8 02 00 00 05 b8 69 8e c0 2b 80 c4 02 00 [15840.675016] EIP: [<c0116a4f>] kmap+0x15/0x56 SS:ESP 0068:cab0bc94 [15840.675016] ---[ end trace 4fea40dad6b70e5f ]--- This happens because the return value of read_mapping_page() is passed on to kmap unchecked. The bug is triggered after the first read_mapping_page() in hfsplus_block_allocate(), this patch fixes all three usages in this functions but leaves the ones further down in the file unchanged. Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 05:04:10 +00:00
if (IS_ERR(page)) {
start = size;
goto out;
}
pptr = kmap(page);
curr = pptr + (offset & (PAGE_CACHE_BITS - 1)) / 32;
i = offset % 32;
offset &= ~(PAGE_CACHE_BITS - 1);
if ((size ^ offset) / PAGE_CACHE_BITS)
end = pptr + PAGE_CACHE_BITS / 32;
else
end = pptr + ((size + 31) & (PAGE_CACHE_BITS - 1)) / 32;
/* scan the first partial u32 for zero bits */
val = *curr;
if (~val) {
n = be32_to_cpu(val);
mask = (1U << 31) >> i;
for (; i < 32; mask >>= 1, i++) {
if (!(n & mask))
goto found;
}
}
curr++;
/* scan complete u32s for the first zero bit */
while (1) {
while (curr < end) {
val = *curr;
if (~val) {
n = be32_to_cpu(val);
mask = 1 << 31;
for (i = 0; i < 32; mask >>= 1, i++) {
if (!(n & mask))
goto found;
}
}
curr++;
}
kunmap(page);
offset += PAGE_CACHE_BITS;
if (offset >= size)
break;
page = read_mapping_page(mapping, offset / PAGE_CACHE_BITS,
NULL);
hfsplus: check read_mapping_page() return value While testing more corrupted images with hfsplus, i came across one which triggered the following bug: [15840.675016] BUG: unable to handle kernel paging request at fffffffb [15840.675016] IP: [<c0116a4f>] kmap+0x15/0x56 [15840.675016] *pde = 00008067 *pte = 00000000 [15840.675016] Oops: 0000 [#1] PREEMPT DEBUG_PAGEALLOC [15840.675016] Modules linked in: [15840.675016] [15840.675016] Pid: 11575, comm: ln Not tainted (2.6.27-rc4-00123-gd3ee1b4-dirty #29) [15840.675016] EIP: 0060:[<c0116a4f>] EFLAGS: 00010202 CPU: 0 [15840.675016] EIP is at kmap+0x15/0x56 [15840.675016] EAX: 00000246 EBX: fffffffb ECX: 00000000 EDX: cab919c0 [15840.675016] ESI: 000007dd EDI: cab0bcf4 EBP: cab0bc98 ESP: cab0bc94 [15840.675016] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 0068 [15840.675016] Process ln (pid: 11575, ti=cab0b000 task=cab919c0 task.ti=cab0b000) [15840.675016] Stack: 00000000 cab0bcdc c0231cfb 00000000 cab0bce0 00000800 ca9290c0 fffffffb [15840.675016] cab145d0 cab919c0 cab15998 22222222 22222222 22222222 00000001 cab15960 [15840.675016] 000007dd cab0bcf4 cab0bd04 c022cb3a cab0bcf4 cab15a6c ca9290c0 00000000 [15840.675016] Call Trace: [15840.675016] [<c0231cfb>] ? hfsplus_block_allocate+0x6f/0x2d3 [15840.675016] [<c022cb3a>] ? hfsplus_file_extend+0xc4/0x1db [15840.675016] [<c022ce41>] ? hfsplus_get_block+0x8c/0x19d [15840.675016] [<c06adde4>] ? sub_preempt_count+0x9d/0xab [15840.675016] [<c019ece6>] ? __block_prepare_write+0x147/0x311 [15840.675016] [<c0161934>] ? __grab_cache_page+0x52/0x73 [15840.675016] [<c019ef4f>] ? block_write_begin+0x79/0xd5 [15840.675016] [<c022cdb5>] ? hfsplus_get_block+0x0/0x19d [15840.675016] [<c019f22a>] ? cont_write_begin+0x27f/0x2af [15840.675016] [<c022cdb5>] ? hfsplus_get_block+0x0/0x19d [15840.675016] [<c0139ebe>] ? tick_program_event+0x28/0x4c [15840.675016] [<c013bd35>] ? trace_hardirqs_off+0xb/0xd [15840.675016] [<c022b723>] ? hfsplus_write_begin+0x2d/0x32 [15840.675016] [<c022cdb5>] ? hfsplus_get_block+0x0/0x19d [15840.675016] [<c0161988>] ? pagecache_write_begin+0x33/0x107 [15840.675016] [<c01879e5>] ? __page_symlink+0x3c/0xae [15840.675016] [<c019ad34>] ? __mark_inode_dirty+0x12f/0x137 [15840.675016] [<c0187a70>] ? page_symlink+0x19/0x1e [15840.675016] [<c022e6eb>] ? hfsplus_symlink+0x41/0xa6 [15840.675016] [<c01886a9>] ? vfs_symlink+0x99/0x101 [15840.675016] [<c018a2f6>] ? sys_symlinkat+0x6b/0xad [15840.675016] [<c018a348>] ? sys_symlink+0x10/0x12 [15840.675016] [<c01038bd>] ? sysenter_do_call+0x12/0x31 [15840.675016] ======================= [15840.675016] Code: 00 00 75 10 83 3d 88 2f ec c0 02 75 07 89 d0 e8 12 56 05 00 5d c3 55 ba 06 00 00 00 89 e5 53 89 c3 b8 3d eb 7e c0 e8 16 74 00 00 <8b> 03 c1 e8 1e 69 c0 d8 02 00 00 05 b8 69 8e c0 2b 80 c4 02 00 [15840.675016] EIP: [<c0116a4f>] kmap+0x15/0x56 SS:ESP 0068:cab0bc94 [15840.675016] ---[ end trace 4fea40dad6b70e5f ]--- This happens because the return value of read_mapping_page() is passed on to kmap unchecked. The bug is triggered after the first read_mapping_page() in hfsplus_block_allocate(), this patch fixes all three usages in this functions but leaves the ones further down in the file unchanged. Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 05:04:10 +00:00
if (IS_ERR(page)) {
start = size;
goto out;
}
curr = pptr = kmap(page);
if ((size ^ offset) / PAGE_CACHE_BITS)
end = pptr + PAGE_CACHE_BITS / 32;
else
end = pptr + ((size + 31) & (PAGE_CACHE_BITS - 1)) / 32;
}
hfs_dbg(BITMAP, "bitmap full\n");
start = size;
goto out;
found:
start = offset + (curr - pptr) * 32 + i;
if (start >= size) {
hfs_dbg(BITMAP, "bitmap full\n");
goto out;
}
/* do any partial u32 at the start */
len = min(size - start, len);
while (1) {
n |= mask;
if (++i >= 32)
break;
mask >>= 1;
if (!--len || n & mask)
goto done;
}
if (!--len)
goto done;
*curr++ = cpu_to_be32(n);
/* do full u32s */
while (1) {
while (curr < end) {
n = be32_to_cpu(*curr);
if (len < 32)
goto last;
if (n) {
len = 32;
goto last;
}
*curr++ = cpu_to_be32(0xffffffff);
len -= 32;
}
set_page_dirty(page);
kunmap(page);
offset += PAGE_CACHE_BITS;
page = read_mapping_page(mapping, offset / PAGE_CACHE_BITS,
NULL);
hfsplus: check read_mapping_page() return value While testing more corrupted images with hfsplus, i came across one which triggered the following bug: [15840.675016] BUG: unable to handle kernel paging request at fffffffb [15840.675016] IP: [<c0116a4f>] kmap+0x15/0x56 [15840.675016] *pde = 00008067 *pte = 00000000 [15840.675016] Oops: 0000 [#1] PREEMPT DEBUG_PAGEALLOC [15840.675016] Modules linked in: [15840.675016] [15840.675016] Pid: 11575, comm: ln Not tainted (2.6.27-rc4-00123-gd3ee1b4-dirty #29) [15840.675016] EIP: 0060:[<c0116a4f>] EFLAGS: 00010202 CPU: 0 [15840.675016] EIP is at kmap+0x15/0x56 [15840.675016] EAX: 00000246 EBX: fffffffb ECX: 00000000 EDX: cab919c0 [15840.675016] ESI: 000007dd EDI: cab0bcf4 EBP: cab0bc98 ESP: cab0bc94 [15840.675016] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 0068 [15840.675016] Process ln (pid: 11575, ti=cab0b000 task=cab919c0 task.ti=cab0b000) [15840.675016] Stack: 00000000 cab0bcdc c0231cfb 00000000 cab0bce0 00000800 ca9290c0 fffffffb [15840.675016] cab145d0 cab919c0 cab15998 22222222 22222222 22222222 00000001 cab15960 [15840.675016] 000007dd cab0bcf4 cab0bd04 c022cb3a cab0bcf4 cab15a6c ca9290c0 00000000 [15840.675016] Call Trace: [15840.675016] [<c0231cfb>] ? hfsplus_block_allocate+0x6f/0x2d3 [15840.675016] [<c022cb3a>] ? hfsplus_file_extend+0xc4/0x1db [15840.675016] [<c022ce41>] ? hfsplus_get_block+0x8c/0x19d [15840.675016] [<c06adde4>] ? sub_preempt_count+0x9d/0xab [15840.675016] [<c019ece6>] ? __block_prepare_write+0x147/0x311 [15840.675016] [<c0161934>] ? __grab_cache_page+0x52/0x73 [15840.675016] [<c019ef4f>] ? block_write_begin+0x79/0xd5 [15840.675016] [<c022cdb5>] ? hfsplus_get_block+0x0/0x19d [15840.675016] [<c019f22a>] ? cont_write_begin+0x27f/0x2af [15840.675016] [<c022cdb5>] ? hfsplus_get_block+0x0/0x19d [15840.675016] [<c0139ebe>] ? tick_program_event+0x28/0x4c [15840.675016] [<c013bd35>] ? trace_hardirqs_off+0xb/0xd [15840.675016] [<c022b723>] ? hfsplus_write_begin+0x2d/0x32 [15840.675016] [<c022cdb5>] ? hfsplus_get_block+0x0/0x19d [15840.675016] [<c0161988>] ? pagecache_write_begin+0x33/0x107 [15840.675016] [<c01879e5>] ? __page_symlink+0x3c/0xae [15840.675016] [<c019ad34>] ? __mark_inode_dirty+0x12f/0x137 [15840.675016] [<c0187a70>] ? page_symlink+0x19/0x1e [15840.675016] [<c022e6eb>] ? hfsplus_symlink+0x41/0xa6 [15840.675016] [<c01886a9>] ? vfs_symlink+0x99/0x101 [15840.675016] [<c018a2f6>] ? sys_symlinkat+0x6b/0xad [15840.675016] [<c018a348>] ? sys_symlink+0x10/0x12 [15840.675016] [<c01038bd>] ? sysenter_do_call+0x12/0x31 [15840.675016] ======================= [15840.675016] Code: 00 00 75 10 83 3d 88 2f ec c0 02 75 07 89 d0 e8 12 56 05 00 5d c3 55 ba 06 00 00 00 89 e5 53 89 c3 b8 3d eb 7e c0 e8 16 74 00 00 <8b> 03 c1 e8 1e 69 c0 d8 02 00 00 05 b8 69 8e c0 2b 80 c4 02 00 [15840.675016] EIP: [<c0116a4f>] kmap+0x15/0x56 SS:ESP 0068:cab0bc94 [15840.675016] ---[ end trace 4fea40dad6b70e5f ]--- This happens because the return value of read_mapping_page() is passed on to kmap unchecked. The bug is triggered after the first read_mapping_page() in hfsplus_block_allocate(), this patch fixes all three usages in this functions but leaves the ones further down in the file unchanged. Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 05:04:10 +00:00
if (IS_ERR(page)) {
start = size;
goto out;
}
pptr = kmap(page);
curr = pptr;
end = pptr + PAGE_CACHE_BITS / 32;
}
last:
/* do any partial u32 at end */
mask = 1U << 31;
for (i = 0; i < len; i++) {
if (n & mask)
break;
n |= mask;
mask >>= 1;
}
done:
*curr = cpu_to_be32(n);
set_page_dirty(page);
kunmap(page);
*max = offset + (curr - pptr) * 32 + i - start;
sbi->free_blocks -= *max;
hfsplus_mark_mdb_dirty(sb);
hfs_dbg(BITMAP, "-> %u,%u\n", start, *max);
out:
mutex_unlock(&sbi->alloc_mutex);
return start;
}
int hfsplus_block_free(struct super_block *sb, u32 offset, u32 count)
{
struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
struct page *page;
struct address_space *mapping;
__be32 *pptr, *curr, *end;
u32 mask, len, pnr;
int i;
/* is there any actual work to be done? */
if (!count)
return 0;
hfs_dbg(BITMAP, "block_free: %u,%u\n", offset, count);
/* are all of the bits in range? */
if ((offset + count) > sbi->total_blocks)
return -ENOENT;
mutex_lock(&sbi->alloc_mutex);
mapping = sbi->alloc_file->i_mapping;
pnr = offset / PAGE_CACHE_BITS;
page = read_mapping_page(mapping, pnr, NULL);
if (IS_ERR(page))
goto kaboom;
pptr = kmap(page);
curr = pptr + (offset & (PAGE_CACHE_BITS - 1)) / 32;
end = pptr + PAGE_CACHE_BITS / 32;
len = count;
/* do any partial u32 at the start */
i = offset % 32;
if (i) {
int j = 32 - i;
mask = 0xffffffffU << j;
if (j > count) {
mask |= 0xffffffffU >> (i + count);
*curr++ &= cpu_to_be32(mask);
goto out;
}
*curr++ &= cpu_to_be32(mask);
count -= j;
}
/* do full u32s */
while (1) {
while (curr < end) {
if (count < 32)
goto done;
*curr++ = 0;
count -= 32;
}
if (!count)
break;
set_page_dirty(page);
kunmap(page);
page = read_mapping_page(mapping, ++pnr, NULL);
if (IS_ERR(page))
goto kaboom;
pptr = kmap(page);
curr = pptr;
end = pptr + PAGE_CACHE_BITS / 32;
}
done:
/* do any partial u32 at end */
if (count) {
mask = 0xffffffffU >> count;
*curr &= cpu_to_be32(mask);
}
out:
set_page_dirty(page);
kunmap(page);
sbi->free_blocks += len;
hfsplus_mark_mdb_dirty(sb);
mutex_unlock(&sbi->alloc_mutex);
return 0;
kaboom:
pr_crit("unable to mark blocks free: error %ld\n", PTR_ERR(page));
mutex_unlock(&sbi->alloc_mutex);
return -EIO;
}