linux-stable/fs/hfsplus/xattr_security.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/xattr_trusted.c
*
* Vyacheslav Dubeyko <slava@dubeyko.com>
*
* Handler for storing security labels as extended attributes.
*/
#include <linux/security.h>
hfsplus: correct usage of HFSPLUS_ATTR_MAX_STRLEN for non-English attributes HFSPLUS_ATTR_MAX_STRLEN (=127) is the limit of attribute names for the number of unicode character (UTF-16BE) storable in the HFS+ file system. Almost all the current usage of it is wrong, in relation to NLS to on-disk conversion. Except for one use calling hfsplus_asc2uni (which should stay the same) and its uses in calling hfsplus_uni2asc (which was corrected in the earlier patch in this series concerning usage of hfsplus_uni2asc), all the other uses are of the forms: - char buffer[size] - bound check: "if (namespace_adjusted_input_length > size) return failure;" Conversion between on-disk unicode representation and NLS char strings (in whichever direction) always needs to accommodate the worst-case NLS conversion, so all char buffers of that size need to have a NLS_MAX_CHARSET_SIZE x . The bound checks are all wrong, since they compare nls_length derived from strlen() to a unicode length limit. It turns out that all the bound-checks do is to protect hfsplus_asc2uni(), which can fail if the input is too large. There is only one usage of it as far as attributes are concerned, in hfsplus_attr_build_key(). It is in turn used by hfsplus_find_attr(), hfsplus_create_attr(), hfsplus_delete_attr(). Thus making sure that errors from hfsplus_asc2uni() is caught in hfsplus_attr_build_key() and propagated is sufficient to replace all the bound checks. Unpropagated errors from hfsplus_asc2uni() in the file catalog code was addressed recently in an independent patch "hfsplus: fix longname handling" by Sougata Santra. Before this patch, trying to set a 55 CJK character (in a UTF-8 locale, > 127/3=42) attribute plus user prefix fails with: $ setfattr -n user.`cat testing-string` -v `cat testing-string` \ testing-string setfattr: testing-string: Operation not supported and retrieving a stored long attributes is particular ugly(!): find /mnt/* -type f -exec getfattr -d {} \; getfattr: /mnt/testing-string: Input/output error with console log: [268008.389781] hfsplus: unicode conversion failed After the patch, both of the above works. FYI, the test attribute string is prepared with: echo -e -n \ "\xe9\x80\x99\xe6\x98\xaf\xe4\xb8\x80\xe5\x80\x8b\xe9\x9d\x9e\xe5" \ "\xb8\xb8\xe6\xbc\xab\xe9\x95\xb7\xe8\x80\x8c\xe6\xa5\xb5\xe5\x85" \ "\xb6\xe4\xb9\x8f\xe5\x91\xb3\xe5\x92\x8c\xe7\x9b\xb8\xe7\x95\xb6" \ "\xe7\x84\xa1\xe8\xb6\xa3\xe3\x80\x81\xe4\xbb\xa5\xe5\x8f\x8a\xe7" \ "\x84\xa1\xe7\x94\xa8\xe7\x9a\x84\xe3\x80\x81\xe5\x86\x8d\xe5\x8a" \ "\xa0\xe4\xb8\x8a\xe6\xaf\xab\xe7\x84\xa1\xe6\x84\x8f\xe7\xbe\xa9" \ "\xe7\x9a\x84\xe6\x93\xb4\xe5\xb1\x95\xe5\xb1\xac\xe6\x80\xa7\xef" \ "\xbc\x8c\xe8\x80\x8c\xe5\x85\xb6\xe5\x94\xaf\xe4\xb8\x80\xe5\x89" \ "\xb5\xe5\xbb\xba\xe7\x9b\xae\xe7\x9a\x84\xe5\x83\x85\xe6\x98\xaf" \ "\xe7\x82\xba\xe4\xba\x86\xe6\xb8\xac\xe8\xa9\xa6\xe4\xbd\x9c\xe7" \ "\x94\xa8\xe3\x80\x82" | tr -d ' ' (= "pointlessly long attribute for testing", elaborate Chinese in UTF-8 enoding). However, it is not possible to set double the size (110 + 5 is still under 127) in a UTF-8 locale: $setfattr -n user.`cat testing-string testing-string` -v \ `cat testing-string testing-string` testing-string setfattr: testing-string: Numerical result out of range 110 CJK char in UTF-8 is 330 bytes - the generic get/set attribute system call code in linux/fs/xattr.c imposes a 255 byte limit. One can use a combination of iconv to encode content, changing terminal locale for viewing, and an nls=cp932/cp936/cp949/cp950 mount option to fully use 127-unicode attribute in a double-byte locale. Also, as an additional information, it is possible to (mis-)use unicode half-width/full-width forms (U+FFxx) to write attributes which looks like english but not actually ascii. Thanks Anton Altaparmakov for reviewing the earlier ideas behind this change. [akpm@linux-foundation.org: fix build] [akpm@linux-foundation.org: fix build] Signed-off-by: Hin-Tak Leung <htl10@users.sourceforge.net> Cc: Anton Altaparmakov <anton@tuxera.com> Cc: Vyacheslav Dubeyko <slava@dubeyko.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@infradead.org> Cc: Sougata Santra <sougata@tuxera.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-06 21:36:22 +00:00
#include <linux/nls.h>
#include "hfsplus_fs.h"
#include "xattr.h"
static int hfsplus_security_getxattr(const struct xattr_handler *handler,
struct dentry *unused, struct inode *inode,
const char *name, void *buffer, size_t size)
{
return hfsplus_getxattr(inode, name, buffer, size,
XATTR_SECURITY_PREFIX,
XATTR_SECURITY_PREFIX_LEN);
}
static int hfsplus_security_setxattr(const struct xattr_handler *handler,
struct mnt_idmap *idmap,
struct dentry *unused, struct inode *inode,
const char *name, const void *buffer,
size_t size, int flags)
{
return hfsplus_setxattr(inode, name, buffer, size, flags,
XATTR_SECURITY_PREFIX,
XATTR_SECURITY_PREFIX_LEN);
}
static int hfsplus_initxattrs(struct inode *inode,
const struct xattr *xattr_array,
void *fs_info)
{
const struct xattr *xattr;
hfsplus: correct usage of HFSPLUS_ATTR_MAX_STRLEN for non-English attributes HFSPLUS_ATTR_MAX_STRLEN (=127) is the limit of attribute names for the number of unicode character (UTF-16BE) storable in the HFS+ file system. Almost all the current usage of it is wrong, in relation to NLS to on-disk conversion. Except for one use calling hfsplus_asc2uni (which should stay the same) and its uses in calling hfsplus_uni2asc (which was corrected in the earlier patch in this series concerning usage of hfsplus_uni2asc), all the other uses are of the forms: - char buffer[size] - bound check: "if (namespace_adjusted_input_length > size) return failure;" Conversion between on-disk unicode representation and NLS char strings (in whichever direction) always needs to accommodate the worst-case NLS conversion, so all char buffers of that size need to have a NLS_MAX_CHARSET_SIZE x . The bound checks are all wrong, since they compare nls_length derived from strlen() to a unicode length limit. It turns out that all the bound-checks do is to protect hfsplus_asc2uni(), which can fail if the input is too large. There is only one usage of it as far as attributes are concerned, in hfsplus_attr_build_key(). It is in turn used by hfsplus_find_attr(), hfsplus_create_attr(), hfsplus_delete_attr(). Thus making sure that errors from hfsplus_asc2uni() is caught in hfsplus_attr_build_key() and propagated is sufficient to replace all the bound checks. Unpropagated errors from hfsplus_asc2uni() in the file catalog code was addressed recently in an independent patch "hfsplus: fix longname handling" by Sougata Santra. Before this patch, trying to set a 55 CJK character (in a UTF-8 locale, > 127/3=42) attribute plus user prefix fails with: $ setfattr -n user.`cat testing-string` -v `cat testing-string` \ testing-string setfattr: testing-string: Operation not supported and retrieving a stored long attributes is particular ugly(!): find /mnt/* -type f -exec getfattr -d {} \; getfattr: /mnt/testing-string: Input/output error with console log: [268008.389781] hfsplus: unicode conversion failed After the patch, both of the above works. FYI, the test attribute string is prepared with: echo -e -n \ "\xe9\x80\x99\xe6\x98\xaf\xe4\xb8\x80\xe5\x80\x8b\xe9\x9d\x9e\xe5" \ "\xb8\xb8\xe6\xbc\xab\xe9\x95\xb7\xe8\x80\x8c\xe6\xa5\xb5\xe5\x85" \ "\xb6\xe4\xb9\x8f\xe5\x91\xb3\xe5\x92\x8c\xe7\x9b\xb8\xe7\x95\xb6" \ "\xe7\x84\xa1\xe8\xb6\xa3\xe3\x80\x81\xe4\xbb\xa5\xe5\x8f\x8a\xe7" \ "\x84\xa1\xe7\x94\xa8\xe7\x9a\x84\xe3\x80\x81\xe5\x86\x8d\xe5\x8a" \ "\xa0\xe4\xb8\x8a\xe6\xaf\xab\xe7\x84\xa1\xe6\x84\x8f\xe7\xbe\xa9" \ "\xe7\x9a\x84\xe6\x93\xb4\xe5\xb1\x95\xe5\xb1\xac\xe6\x80\xa7\xef" \ "\xbc\x8c\xe8\x80\x8c\xe5\x85\xb6\xe5\x94\xaf\xe4\xb8\x80\xe5\x89" \ "\xb5\xe5\xbb\xba\xe7\x9b\xae\xe7\x9a\x84\xe5\x83\x85\xe6\x98\xaf" \ "\xe7\x82\xba\xe4\xba\x86\xe6\xb8\xac\xe8\xa9\xa6\xe4\xbd\x9c\xe7" \ "\x94\xa8\xe3\x80\x82" | tr -d ' ' (= "pointlessly long attribute for testing", elaborate Chinese in UTF-8 enoding). However, it is not possible to set double the size (110 + 5 is still under 127) in a UTF-8 locale: $setfattr -n user.`cat testing-string testing-string` -v \ `cat testing-string testing-string` testing-string setfattr: testing-string: Numerical result out of range 110 CJK char in UTF-8 is 330 bytes - the generic get/set attribute system call code in linux/fs/xattr.c imposes a 255 byte limit. One can use a combination of iconv to encode content, changing terminal locale for viewing, and an nls=cp932/cp936/cp949/cp950 mount option to fully use 127-unicode attribute in a double-byte locale. Also, as an additional information, it is possible to (mis-)use unicode half-width/full-width forms (U+FFxx) to write attributes which looks like english but not actually ascii. Thanks Anton Altaparmakov for reviewing the earlier ideas behind this change. [akpm@linux-foundation.org: fix build] [akpm@linux-foundation.org: fix build] Signed-off-by: Hin-Tak Leung <htl10@users.sourceforge.net> Cc: Anton Altaparmakov <anton@tuxera.com> Cc: Vyacheslav Dubeyko <slava@dubeyko.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@infradead.org> Cc: Sougata Santra <sougata@tuxera.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-06 21:36:22 +00:00
char *xattr_name;
int err = 0;
hfsplus: correct usage of HFSPLUS_ATTR_MAX_STRLEN for non-English attributes HFSPLUS_ATTR_MAX_STRLEN (=127) is the limit of attribute names for the number of unicode character (UTF-16BE) storable in the HFS+ file system. Almost all the current usage of it is wrong, in relation to NLS to on-disk conversion. Except for one use calling hfsplus_asc2uni (which should stay the same) and its uses in calling hfsplus_uni2asc (which was corrected in the earlier patch in this series concerning usage of hfsplus_uni2asc), all the other uses are of the forms: - char buffer[size] - bound check: "if (namespace_adjusted_input_length > size) return failure;" Conversion between on-disk unicode representation and NLS char strings (in whichever direction) always needs to accommodate the worst-case NLS conversion, so all char buffers of that size need to have a NLS_MAX_CHARSET_SIZE x . The bound checks are all wrong, since they compare nls_length derived from strlen() to a unicode length limit. It turns out that all the bound-checks do is to protect hfsplus_asc2uni(), which can fail if the input is too large. There is only one usage of it as far as attributes are concerned, in hfsplus_attr_build_key(). It is in turn used by hfsplus_find_attr(), hfsplus_create_attr(), hfsplus_delete_attr(). Thus making sure that errors from hfsplus_asc2uni() is caught in hfsplus_attr_build_key() and propagated is sufficient to replace all the bound checks. Unpropagated errors from hfsplus_asc2uni() in the file catalog code was addressed recently in an independent patch "hfsplus: fix longname handling" by Sougata Santra. Before this patch, trying to set a 55 CJK character (in a UTF-8 locale, > 127/3=42) attribute plus user prefix fails with: $ setfattr -n user.`cat testing-string` -v `cat testing-string` \ testing-string setfattr: testing-string: Operation not supported and retrieving a stored long attributes is particular ugly(!): find /mnt/* -type f -exec getfattr -d {} \; getfattr: /mnt/testing-string: Input/output error with console log: [268008.389781] hfsplus: unicode conversion failed After the patch, both of the above works. FYI, the test attribute string is prepared with: echo -e -n \ "\xe9\x80\x99\xe6\x98\xaf\xe4\xb8\x80\xe5\x80\x8b\xe9\x9d\x9e\xe5" \ "\xb8\xb8\xe6\xbc\xab\xe9\x95\xb7\xe8\x80\x8c\xe6\xa5\xb5\xe5\x85" \ "\xb6\xe4\xb9\x8f\xe5\x91\xb3\xe5\x92\x8c\xe7\x9b\xb8\xe7\x95\xb6" \ "\xe7\x84\xa1\xe8\xb6\xa3\xe3\x80\x81\xe4\xbb\xa5\xe5\x8f\x8a\xe7" \ "\x84\xa1\xe7\x94\xa8\xe7\x9a\x84\xe3\x80\x81\xe5\x86\x8d\xe5\x8a" \ "\xa0\xe4\xb8\x8a\xe6\xaf\xab\xe7\x84\xa1\xe6\x84\x8f\xe7\xbe\xa9" \ "\xe7\x9a\x84\xe6\x93\xb4\xe5\xb1\x95\xe5\xb1\xac\xe6\x80\xa7\xef" \ "\xbc\x8c\xe8\x80\x8c\xe5\x85\xb6\xe5\x94\xaf\xe4\xb8\x80\xe5\x89" \ "\xb5\xe5\xbb\xba\xe7\x9b\xae\xe7\x9a\x84\xe5\x83\x85\xe6\x98\xaf" \ "\xe7\x82\xba\xe4\xba\x86\xe6\xb8\xac\xe8\xa9\xa6\xe4\xbd\x9c\xe7" \ "\x94\xa8\xe3\x80\x82" | tr -d ' ' (= "pointlessly long attribute for testing", elaborate Chinese in UTF-8 enoding). However, it is not possible to set double the size (110 + 5 is still under 127) in a UTF-8 locale: $setfattr -n user.`cat testing-string testing-string` -v \ `cat testing-string testing-string` testing-string setfattr: testing-string: Numerical result out of range 110 CJK char in UTF-8 is 330 bytes - the generic get/set attribute system call code in linux/fs/xattr.c imposes a 255 byte limit. One can use a combination of iconv to encode content, changing terminal locale for viewing, and an nls=cp932/cp936/cp949/cp950 mount option to fully use 127-unicode attribute in a double-byte locale. Also, as an additional information, it is possible to (mis-)use unicode half-width/full-width forms (U+FFxx) to write attributes which looks like english but not actually ascii. Thanks Anton Altaparmakov for reviewing the earlier ideas behind this change. [akpm@linux-foundation.org: fix build] [akpm@linux-foundation.org: fix build] Signed-off-by: Hin-Tak Leung <htl10@users.sourceforge.net> Cc: Anton Altaparmakov <anton@tuxera.com> Cc: Vyacheslav Dubeyko <slava@dubeyko.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@infradead.org> Cc: Sougata Santra <sougata@tuxera.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-06 21:36:22 +00:00
xattr_name = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN + 1,
GFP_KERNEL);
if (!xattr_name)
return -ENOMEM;
for (xattr = xattr_array; xattr->name != NULL; xattr++) {
hfsplus: correct usage of HFSPLUS_ATTR_MAX_STRLEN for non-English attributes HFSPLUS_ATTR_MAX_STRLEN (=127) is the limit of attribute names for the number of unicode character (UTF-16BE) storable in the HFS+ file system. Almost all the current usage of it is wrong, in relation to NLS to on-disk conversion. Except for one use calling hfsplus_asc2uni (which should stay the same) and its uses in calling hfsplus_uni2asc (which was corrected in the earlier patch in this series concerning usage of hfsplus_uni2asc), all the other uses are of the forms: - char buffer[size] - bound check: "if (namespace_adjusted_input_length > size) return failure;" Conversion between on-disk unicode representation and NLS char strings (in whichever direction) always needs to accommodate the worst-case NLS conversion, so all char buffers of that size need to have a NLS_MAX_CHARSET_SIZE x . The bound checks are all wrong, since they compare nls_length derived from strlen() to a unicode length limit. It turns out that all the bound-checks do is to protect hfsplus_asc2uni(), which can fail if the input is too large. There is only one usage of it as far as attributes are concerned, in hfsplus_attr_build_key(). It is in turn used by hfsplus_find_attr(), hfsplus_create_attr(), hfsplus_delete_attr(). Thus making sure that errors from hfsplus_asc2uni() is caught in hfsplus_attr_build_key() and propagated is sufficient to replace all the bound checks. Unpropagated errors from hfsplus_asc2uni() in the file catalog code was addressed recently in an independent patch "hfsplus: fix longname handling" by Sougata Santra. Before this patch, trying to set a 55 CJK character (in a UTF-8 locale, > 127/3=42) attribute plus user prefix fails with: $ setfattr -n user.`cat testing-string` -v `cat testing-string` \ testing-string setfattr: testing-string: Operation not supported and retrieving a stored long attributes is particular ugly(!): find /mnt/* -type f -exec getfattr -d {} \; getfattr: /mnt/testing-string: Input/output error with console log: [268008.389781] hfsplus: unicode conversion failed After the patch, both of the above works. FYI, the test attribute string is prepared with: echo -e -n \ "\xe9\x80\x99\xe6\x98\xaf\xe4\xb8\x80\xe5\x80\x8b\xe9\x9d\x9e\xe5" \ "\xb8\xb8\xe6\xbc\xab\xe9\x95\xb7\xe8\x80\x8c\xe6\xa5\xb5\xe5\x85" \ "\xb6\xe4\xb9\x8f\xe5\x91\xb3\xe5\x92\x8c\xe7\x9b\xb8\xe7\x95\xb6" \ "\xe7\x84\xa1\xe8\xb6\xa3\xe3\x80\x81\xe4\xbb\xa5\xe5\x8f\x8a\xe7" \ "\x84\xa1\xe7\x94\xa8\xe7\x9a\x84\xe3\x80\x81\xe5\x86\x8d\xe5\x8a" \ "\xa0\xe4\xb8\x8a\xe6\xaf\xab\xe7\x84\xa1\xe6\x84\x8f\xe7\xbe\xa9" \ "\xe7\x9a\x84\xe6\x93\xb4\xe5\xb1\x95\xe5\xb1\xac\xe6\x80\xa7\xef" \ "\xbc\x8c\xe8\x80\x8c\xe5\x85\xb6\xe5\x94\xaf\xe4\xb8\x80\xe5\x89" \ "\xb5\xe5\xbb\xba\xe7\x9b\xae\xe7\x9a\x84\xe5\x83\x85\xe6\x98\xaf" \ "\xe7\x82\xba\xe4\xba\x86\xe6\xb8\xac\xe8\xa9\xa6\xe4\xbd\x9c\xe7" \ "\x94\xa8\xe3\x80\x82" | tr -d ' ' (= "pointlessly long attribute for testing", elaborate Chinese in UTF-8 enoding). However, it is not possible to set double the size (110 + 5 is still under 127) in a UTF-8 locale: $setfattr -n user.`cat testing-string testing-string` -v \ `cat testing-string testing-string` testing-string setfattr: testing-string: Numerical result out of range 110 CJK char in UTF-8 is 330 bytes - the generic get/set attribute system call code in linux/fs/xattr.c imposes a 255 byte limit. One can use a combination of iconv to encode content, changing terminal locale for viewing, and an nls=cp932/cp936/cp949/cp950 mount option to fully use 127-unicode attribute in a double-byte locale. Also, as an additional information, it is possible to (mis-)use unicode half-width/full-width forms (U+FFxx) to write attributes which looks like english but not actually ascii. Thanks Anton Altaparmakov for reviewing the earlier ideas behind this change. [akpm@linux-foundation.org: fix build] [akpm@linux-foundation.org: fix build] Signed-off-by: Hin-Tak Leung <htl10@users.sourceforge.net> Cc: Anton Altaparmakov <anton@tuxera.com> Cc: Vyacheslav Dubeyko <slava@dubeyko.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@infradead.org> Cc: Sougata Santra <sougata@tuxera.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-06 21:36:22 +00:00
if (!strcmp(xattr->name, ""))
continue;
strcpy(xattr_name, XATTR_SECURITY_PREFIX);
strcpy(xattr_name +
XATTR_SECURITY_PREFIX_LEN, xattr->name);
memset(xattr_name +
hfsplus: correct usage of HFSPLUS_ATTR_MAX_STRLEN for non-English attributes HFSPLUS_ATTR_MAX_STRLEN (=127) is the limit of attribute names for the number of unicode character (UTF-16BE) storable in the HFS+ file system. Almost all the current usage of it is wrong, in relation to NLS to on-disk conversion. Except for one use calling hfsplus_asc2uni (which should stay the same) and its uses in calling hfsplus_uni2asc (which was corrected in the earlier patch in this series concerning usage of hfsplus_uni2asc), all the other uses are of the forms: - char buffer[size] - bound check: "if (namespace_adjusted_input_length > size) return failure;" Conversion between on-disk unicode representation and NLS char strings (in whichever direction) always needs to accommodate the worst-case NLS conversion, so all char buffers of that size need to have a NLS_MAX_CHARSET_SIZE x . The bound checks are all wrong, since they compare nls_length derived from strlen() to a unicode length limit. It turns out that all the bound-checks do is to protect hfsplus_asc2uni(), which can fail if the input is too large. There is only one usage of it as far as attributes are concerned, in hfsplus_attr_build_key(). It is in turn used by hfsplus_find_attr(), hfsplus_create_attr(), hfsplus_delete_attr(). Thus making sure that errors from hfsplus_asc2uni() is caught in hfsplus_attr_build_key() and propagated is sufficient to replace all the bound checks. Unpropagated errors from hfsplus_asc2uni() in the file catalog code was addressed recently in an independent patch "hfsplus: fix longname handling" by Sougata Santra. Before this patch, trying to set a 55 CJK character (in a UTF-8 locale, > 127/3=42) attribute plus user prefix fails with: $ setfattr -n user.`cat testing-string` -v `cat testing-string` \ testing-string setfattr: testing-string: Operation not supported and retrieving a stored long attributes is particular ugly(!): find /mnt/* -type f -exec getfattr -d {} \; getfattr: /mnt/testing-string: Input/output error with console log: [268008.389781] hfsplus: unicode conversion failed After the patch, both of the above works. FYI, the test attribute string is prepared with: echo -e -n \ "\xe9\x80\x99\xe6\x98\xaf\xe4\xb8\x80\xe5\x80\x8b\xe9\x9d\x9e\xe5" \ "\xb8\xb8\xe6\xbc\xab\xe9\x95\xb7\xe8\x80\x8c\xe6\xa5\xb5\xe5\x85" \ "\xb6\xe4\xb9\x8f\xe5\x91\xb3\xe5\x92\x8c\xe7\x9b\xb8\xe7\x95\xb6" \ "\xe7\x84\xa1\xe8\xb6\xa3\xe3\x80\x81\xe4\xbb\xa5\xe5\x8f\x8a\xe7" \ "\x84\xa1\xe7\x94\xa8\xe7\x9a\x84\xe3\x80\x81\xe5\x86\x8d\xe5\x8a" \ "\xa0\xe4\xb8\x8a\xe6\xaf\xab\xe7\x84\xa1\xe6\x84\x8f\xe7\xbe\xa9" \ "\xe7\x9a\x84\xe6\x93\xb4\xe5\xb1\x95\xe5\xb1\xac\xe6\x80\xa7\xef" \ "\xbc\x8c\xe8\x80\x8c\xe5\x85\xb6\xe5\x94\xaf\xe4\xb8\x80\xe5\x89" \ "\xb5\xe5\xbb\xba\xe7\x9b\xae\xe7\x9a\x84\xe5\x83\x85\xe6\x98\xaf" \ "\xe7\x82\xba\xe4\xba\x86\xe6\xb8\xac\xe8\xa9\xa6\xe4\xbd\x9c\xe7" \ "\x94\xa8\xe3\x80\x82" | tr -d ' ' (= "pointlessly long attribute for testing", elaborate Chinese in UTF-8 enoding). However, it is not possible to set double the size (110 + 5 is still under 127) in a UTF-8 locale: $setfattr -n user.`cat testing-string testing-string` -v \ `cat testing-string testing-string` testing-string setfattr: testing-string: Numerical result out of range 110 CJK char in UTF-8 is 330 bytes - the generic get/set attribute system call code in linux/fs/xattr.c imposes a 255 byte limit. One can use a combination of iconv to encode content, changing terminal locale for viewing, and an nls=cp932/cp936/cp949/cp950 mount option to fully use 127-unicode attribute in a double-byte locale. Also, as an additional information, it is possible to (mis-)use unicode half-width/full-width forms (U+FFxx) to write attributes which looks like english but not actually ascii. Thanks Anton Altaparmakov for reviewing the earlier ideas behind this change. [akpm@linux-foundation.org: fix build] [akpm@linux-foundation.org: fix build] Signed-off-by: Hin-Tak Leung <htl10@users.sourceforge.net> Cc: Anton Altaparmakov <anton@tuxera.com> Cc: Vyacheslav Dubeyko <slava@dubeyko.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@infradead.org> Cc: Sougata Santra <sougata@tuxera.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-06 21:36:22 +00:00
XATTR_SECURITY_PREFIX_LEN + strlen(xattr->name), 0, 1);
err = __hfsplus_setxattr(inode, xattr_name,
xattr->value, xattr->value_len, 0);
if (err)
break;
}
hfsplus: correct usage of HFSPLUS_ATTR_MAX_STRLEN for non-English attributes HFSPLUS_ATTR_MAX_STRLEN (=127) is the limit of attribute names for the number of unicode character (UTF-16BE) storable in the HFS+ file system. Almost all the current usage of it is wrong, in relation to NLS to on-disk conversion. Except for one use calling hfsplus_asc2uni (which should stay the same) and its uses in calling hfsplus_uni2asc (which was corrected in the earlier patch in this series concerning usage of hfsplus_uni2asc), all the other uses are of the forms: - char buffer[size] - bound check: "if (namespace_adjusted_input_length > size) return failure;" Conversion between on-disk unicode representation and NLS char strings (in whichever direction) always needs to accommodate the worst-case NLS conversion, so all char buffers of that size need to have a NLS_MAX_CHARSET_SIZE x . The bound checks are all wrong, since they compare nls_length derived from strlen() to a unicode length limit. It turns out that all the bound-checks do is to protect hfsplus_asc2uni(), which can fail if the input is too large. There is only one usage of it as far as attributes are concerned, in hfsplus_attr_build_key(). It is in turn used by hfsplus_find_attr(), hfsplus_create_attr(), hfsplus_delete_attr(). Thus making sure that errors from hfsplus_asc2uni() is caught in hfsplus_attr_build_key() and propagated is sufficient to replace all the bound checks. Unpropagated errors from hfsplus_asc2uni() in the file catalog code was addressed recently in an independent patch "hfsplus: fix longname handling" by Sougata Santra. Before this patch, trying to set a 55 CJK character (in a UTF-8 locale, > 127/3=42) attribute plus user prefix fails with: $ setfattr -n user.`cat testing-string` -v `cat testing-string` \ testing-string setfattr: testing-string: Operation not supported and retrieving a stored long attributes is particular ugly(!): find /mnt/* -type f -exec getfattr -d {} \; getfattr: /mnt/testing-string: Input/output error with console log: [268008.389781] hfsplus: unicode conversion failed After the patch, both of the above works. FYI, the test attribute string is prepared with: echo -e -n \ "\xe9\x80\x99\xe6\x98\xaf\xe4\xb8\x80\xe5\x80\x8b\xe9\x9d\x9e\xe5" \ "\xb8\xb8\xe6\xbc\xab\xe9\x95\xb7\xe8\x80\x8c\xe6\xa5\xb5\xe5\x85" \ "\xb6\xe4\xb9\x8f\xe5\x91\xb3\xe5\x92\x8c\xe7\x9b\xb8\xe7\x95\xb6" \ "\xe7\x84\xa1\xe8\xb6\xa3\xe3\x80\x81\xe4\xbb\xa5\xe5\x8f\x8a\xe7" \ "\x84\xa1\xe7\x94\xa8\xe7\x9a\x84\xe3\x80\x81\xe5\x86\x8d\xe5\x8a" \ "\xa0\xe4\xb8\x8a\xe6\xaf\xab\xe7\x84\xa1\xe6\x84\x8f\xe7\xbe\xa9" \ "\xe7\x9a\x84\xe6\x93\xb4\xe5\xb1\x95\xe5\xb1\xac\xe6\x80\xa7\xef" \ "\xbc\x8c\xe8\x80\x8c\xe5\x85\xb6\xe5\x94\xaf\xe4\xb8\x80\xe5\x89" \ "\xb5\xe5\xbb\xba\xe7\x9b\xae\xe7\x9a\x84\xe5\x83\x85\xe6\x98\xaf" \ "\xe7\x82\xba\xe4\xba\x86\xe6\xb8\xac\xe8\xa9\xa6\xe4\xbd\x9c\xe7" \ "\x94\xa8\xe3\x80\x82" | tr -d ' ' (= "pointlessly long attribute for testing", elaborate Chinese in UTF-8 enoding). However, it is not possible to set double the size (110 + 5 is still under 127) in a UTF-8 locale: $setfattr -n user.`cat testing-string testing-string` -v \ `cat testing-string testing-string` testing-string setfattr: testing-string: Numerical result out of range 110 CJK char in UTF-8 is 330 bytes - the generic get/set attribute system call code in linux/fs/xattr.c imposes a 255 byte limit. One can use a combination of iconv to encode content, changing terminal locale for viewing, and an nls=cp932/cp936/cp949/cp950 mount option to fully use 127-unicode attribute in a double-byte locale. Also, as an additional information, it is possible to (mis-)use unicode half-width/full-width forms (U+FFxx) to write attributes which looks like english but not actually ascii. Thanks Anton Altaparmakov for reviewing the earlier ideas behind this change. [akpm@linux-foundation.org: fix build] [akpm@linux-foundation.org: fix build] Signed-off-by: Hin-Tak Leung <htl10@users.sourceforge.net> Cc: Anton Altaparmakov <anton@tuxera.com> Cc: Vyacheslav Dubeyko <slava@dubeyko.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@infradead.org> Cc: Sougata Santra <sougata@tuxera.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-06 21:36:22 +00:00
kfree(xattr_name);
return err;
}
int hfsplus_init_security(struct inode *inode, struct inode *dir,
const struct qstr *qstr)
{
return security_inode_init_security(inode, dir, qstr,
&hfsplus_initxattrs, NULL);
}
const struct xattr_handler hfsplus_xattr_security_handler = {
.prefix = XATTR_SECURITY_PREFIX,
.get = hfsplus_security_getxattr,
.set = hfsplus_security_setxattr,
};