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2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+1
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>
2016-08-05nfsd: check d_can_lookup in fh_verify of directoriesJ. Bruce Fields1-4/+10
Create and other nfsd ops generally assume we can call lookup_one_len on inodes with S_IFDIR set. Al says that this assumption isn't true in general, though it should be for the filesystem objects nfsd sees. Add a check just to make sure our assumption isn't violated. Remove a couple checks for i_op->lookup in create code. Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-07-13nfsd: Fix some indent inconsistancyChristophe JAILLET1-1/+1
Silent a few smatch warnings about indentation Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-07-13nfsd: Correct a comment for NFSD_MAY_ defines locationOleg Drokin1-1/+1
Those are now defined in fs/nfsd/vfs.h Signed-off-by: Oleg Drokin <green@linuxhacker.ru> Reviewed-by: Jeff Layton <jlayton@poochiereds.net> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-04-11don't bother with ->d_inode->i_sb - it's always equal to ->d_sbAl Viro1-1/+1
... and neither can ever be NULL Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-10-13nfsd: switch unsigned char flags in svc_fh to boolsJeff Layton1-4/+1
...just for clarity. Signed-off-by: Jeff Layton <jeff.layton@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2015-04-15VFS: normal filesystems (and lustre): d_inode() annotationsDavid Howells1-10/+10
that's the bulk of filesystem drivers dealing with inodes of their own Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-22VFS: (Scripted) Convert S_ISLNK/DIR/REG(dentry->d_inode) to d_is_*(dentry)David Howells1-4/+4
Convert the following where appropriate: (1) S_ISLNK(dentry->d_inode) to d_is_symlink(dentry). (2) S_ISREG(dentry->d_inode) to d_is_reg(dentry). (3) S_ISDIR(dentry->d_inode) to d_is_dir(dentry). This is actually more complicated than it appears as some calls should be converted to d_can_lookup() instead. The difference is whether the directory in question is a real dir with a ->lookup op or whether it's a fake dir with a ->d_automount op. In some circumstances, we can subsume checks for dentry->d_inode not being NULL into this, provided we the code isn't in a filesystem that expects d_inode to be NULL if the dirent really *is* negative (ie. if we're going to use d_inode() rather than d_backing_inode() to get the inode pointer). Note that the dentry type field may be set to something other than DCACHE_MISS_TYPE when d_inode is NULL in the case of unionmount, where the VFS manages the fall-through from a negative dentry to a lower layer. In such a case, the dentry type of the negative union dentry is set to the same as the type of the lower dentry. However, if you know d_inode is not NULL at the call site, then you can use the d_is_xxx() functions even in a filesystem. There is one further complication: a 0,0 chardev dentry may be labelled DCACHE_WHITEOUT_TYPE rather than DCACHE_SPECIAL_TYPE. Strictly, this was intended for special directory entry types that don't have attached inodes. The following perl+coccinelle script was used: use strict; my @callers; open($fd, 'git grep -l \'S_IS[A-Z].*->d_inode\' |') || die "Can't grep for S_ISDIR and co. callers"; @callers = <$fd>; close($fd); unless (@callers) { print "No matches\n"; exit(0); } my @cocci = ( '@@', 'expression E;', '@@', '', '- S_ISLNK(E->d_inode->i_mode)', '+ d_is_symlink(E)', '', '@@', 'expression E;', '@@', '', '- S_ISDIR(E->d_inode->i_mode)', '+ d_is_dir(E)', '', '@@', 'expression E;', '@@', '', '- S_ISREG(E->d_inode->i_mode)', '+ d_is_reg(E)' ); my $coccifile = "tmp.sp.cocci"; open($fd, ">$coccifile") || die $coccifile; print($fd "$_\n") || die $coccifile foreach (@cocci); close($fd); foreach my $file (@callers) { chomp $file; print "Processing ", $file, "\n"; system("spatch", "--sp-file", $coccifile, $file, "--in-place", "--no-show-diff") == 0 || die "spatch failed"; } [AV: overlayfs parts skipped] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-12-09sunrpc: add a generic rq_flags field to svc_rqst and move rq_secure to itJeff Layton1-1/+1
In a later patch, we're going to need some atomic bit flags. Since that field will need to be an unsigned long, we mitigate that space consumption by migrating some other bitflags to the new field. Start with the rq_secure flag. Signed-off-by: Jeff Layton <jlayton@primarydata.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-09-04NFSD: Put export if prepare_creds() failKinglong Mee1-2/+4
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-06-23nfsd: add appropriate __force directives to filehandle generation codeJeff Layton1-1/+8
The filehandle structs all use host-endian values, but will sometimes stuff big-endian values into those fields. This is OK since these values are opaque to the client, but it confuses sparse. Add __force to make it clear that we are doing this intentionally. Signed-off-by: Jeff Layton <jlayton@primarydata.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-06-23NFSD: Using exp_get for export gettingKinglong Mee1-2/+1
Don't using cache_get besides export.h, using exp_get for export. Signed-off-by: Kinglong Mee <kinglongmee@gmail.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-05-31SUNRPC/NFSD: Remove using of dprintk with KERN_WARNINGKinglong Mee1-3/+2
When debugging, rpc prints messages from dprintk(KERN_WARNING ...) with "^A4" prefixed, [ 2780.339988] ^A4nfsd: connect from unprivileged port: 127.0.0.1, port=35316 Trond tells, > dprintk != printk. We have NEVER supported dprintk(KERN_WARNING...) This patch removes using of dprintk with KERN_WARNING. Signed-off-by: Kinglong Mee <kinglongmee@gmail.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-05-08nfsd: clean up fh_auth usageChristoph Hellwig1-11/+9
Use fh_fsid when reffering to the fsid part of the filehandle. The variable length auth field envisioned in nfsfh wasn't ever implemented. Also clean up some lose ends around this and document the file handle format better. Btw, why do we even export nfsfh.h to userspace? The file handle very much is kernel private, and nothing in nfs-utils include the header either. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-10-30nfsd: fh_update should error out in unexpected casesJ. Bruce Fields1-5/+3
The reporter saw a NULL dereference when a filesystem's ->mknod returned success but left the dentry negative, and then nfsd tried to dereference d_inode (in this case because the CREATE was followed by a GETATTR in the same nfsv4 compound). fh_update already checks for this and another broken case, but for some reason it returns success and leaves nfsd trying to soldier on. If it failed we'd avoid the crash. There's only so much we can do with a buggy filesystem, but it's easy enough to bail out here, so let's do that. Reported-by: Antti Tönkyrä <daedalus@pingtimeout.net> Tested-by: Antti Tönkyrä <daedalus@pingtimeout.net> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2013-10-03nfsd: switch to %p[dD]Al Viro1-15/+13
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-11-08exportfs: add FILEID_INVALID to indicate invalid fid_typeNamjae Jeon1-2/+2
This commit adds FILEID_INVALID = 0xff in fid_type to indicate invalid fid_type It avoids using magic number 255 Signed-off-by: Namjae Jeon <linkinjeon@gmail.com> Signed-off-by: Vivek Trivedi <vtrivedi018@gmail.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-07-31nfsd: Push mnt_want_write() outside of i_mutexJan Kara1-0/+1
When mnt_want_write() starts to handle freezing it will get a full lock semantics requiring proper lock ordering. So push mnt_want_write() call consistently outside of i_mutex. CC: linux-nfs@vger.kernel.org CC: "J. Bruce Fields" <bfields@fieldses.org> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-04-12nfsd: use exp_put() for svc_export_cache putStanislav Kinsbursky1-1/+1
This patch replaces cache_put() call for svc_export_cache by exp_put() call. Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2012-01-04fs: propagate umode_t, misc bitsAl Viro1-2/+2
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-08-27nfsd: clean up nfsd_mode_check()J. Bruce Fields1-12/+18
Add some more comments, simplify logic, do & S_IFMT just once, name "type" more helpfully. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2011-08-27nfsd: open-code special directory-hardlink checkJ. Bruce Fields1-9/+0
We allow the fh_verify caller to specify that any object *except* those of a given type is allowed, by passing a negative type. But only one caller actually uses it. Open-code that check in the one caller. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2011-04-11nfsd4: allow fh_verify caller to skip pseudoflavor checksJ. Bruce Fields1-1/+1
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2009-12-21nfsd: fix "insecure" export optionJ. Bruce Fields1-1/+1
A typo in 12045a6ee9908b "nfsd: let "insecure" flag vary by pseudoflavor" reversed the sense of the "insecure" flag. Reported-by: Michael Guntsche <mike@it-loops.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-15nfsd: remove pointless paths in file headersJ. Bruce Fields1-2/+0
The new .h files have paths at the top that are now out of date. While we're here, just remove all of those from fs/nfsd; they never served any purpose. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-12-15nfsd: restrict filehandles accepted in V4ROOT caseSteve Dickson1-0/+34
On V4ROOT exports, only accept filehandles that are the *root* of some export. This allows mountd to allow or deny access to individual directories and symlinks on the pseudofilesystem. Note that the checks in readdir and lookup are not enough, since a malicious host with access to the network could guess filehandles that they weren't able to obtain through lookup or readdir. Signed-off-by: Steve Dickson <steved@redhat.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-12-15nfsd: let "insecure" flag vary by pseudoflavorJ. Bruce Fields1-1/+3
This was an oversight; it should be among the export flags that can be allowed to vary by pseudoflavor. This allows an administrator to (for example) allow auth_sys mounts only from low ports, but allow auth_krb5 mounts to use any port. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-12-15nfsd: Move private headers to source directoryBoaz Harrosh1-1/+1
Lots of include/linux/nfsd/* headers are only used by nfsd module. Move them to the source directory Signed-off-by: Boaz Harrosh <bharrosh@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-12-15nfsd: Source files #include cleanupsBoaz Harrosh1-9/+0
Now that the headers are fixed and carry their own wait, all fs/nfsd/ source files can include a minimal set of headers. and still compile just fine. This patch should improve the compilation speed of the nfsd module. Signed-off-by: Boaz Harrosh <bharrosh@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-11-26nfsd: simplify fh_verify access checksJ. Bruce Fields1-29/+21
All nfsd security depends on the security checks in fh_verify, and especially on nfsd_setuser(). It therefore bothers me that the nfsd_setuser call may be made from three different places, depending on whether the filehandle has already been mapped to a dentry, and on whether subtreechecking is in force. Instead, make an unconditional call in fh_verify(), so it's trivial to verify that the call always occurs. That leaves us with a redundant nfsd_setuser() call in the subtreecheck case--it needs the correct user set earlier in order to check execute permissions on the path to this filehandle--but I'm willing to accept that minor inefficiency in the subtreecheck case in return for more straightforward permission checking. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-11-13nfsd: make fs/nfsd/vfs.h for common includesJ. Bruce Fields1-0/+1
None of this stuff is used outside nfsd, so move it out of the common linux include directory. Actually, probably none of the stuff in include/linux/nfsd/nfsd.h really belongs there, so later we may remove that file entirely. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-09-04nfsd4: filehandle leak or error exit from fh_compose()J. Bruce Fields1-1/+3
A number of callers (nfsd4_encode_fattr(), at least) don't bother to release the filehandle returned to fh_compose() if fh_compose() returns an error. So, modify fh_compose() to release the filehandle before returning an error. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-09-03nfsd: move fsid_type choice out of fh_composeJ. Bruce Fields1-36/+41
More trivial cleanup. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-09-03nfsd: move some of fh_compose into helper functionsJ. Bruce Fields1-38/+45
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-05-27knfsd: remove unreported filehandle stats countersGreg Banks1-6/+0
The file nfsfh.c contains two static variables nfsd_nr_verified and nfsd_nr_put. These are counters which are incremented as a side effect of the fh_verify() fh_compose() and fh_put() operations, i.e. at least twice per NFS call for any non-trivial workload. Needless to say this makes the cacheline that contains them (and any other innocent victims) a very hot contention point indeed under high call-rate workloads on multiprocessor NFS server. It also turns out that these counters are not used anywhere. They're not reported to userspace, they're not used in logic, they're not even exported from the object file (let alone the module). All they do is waste CPU time. So this patch removes them. Tests on a 16 CPU Altix A4700 with 2 10gige Myricom cards, configured separately (no bonding). Workload is 640 client threads doing directory traverals with random small reads, from server RAM. Before ====== Kernel profile: % cumulative self self total time samples samples calls 1/call 1/call name 6.05 2716.00 2716.00 30406 0.09 1.02 svc_process 4.44 4706.00 1990.00 1975 1.01 1.01 spin_unlock_irqrestore 3.72 6376.00 1670.00 1666 1.00 1.00 svc_export_put 3.41 7907.00 1531.00 1786 0.86 1.02 nfsd_ofcache_lookup 3.25 9363.00 1456.00 10965 0.13 1.01 nfsd_dispatch 3.10 10752.00 1389.00 1376 1.01 1.01 nfsd_cache_lookup 2.57 11907.00 1155.00 4517 0.26 1.03 svc_tcp_recvfrom ... 2.21 15352.00 1003.00 1081 0.93 1.00 nfsd_choose_ofc <---- ^^^^ Here the function nfsd_choose_ofc() reads a global variable which by accident happened to be located in the same cacheline as nfsd_nr_verified. Call rate: nullarbor:~ # pmdumptext nfs3.server.calls ... Thu Dec 13 00:15:27 184780.663 Thu Dec 13 00:15:28 184885.881 Thu Dec 13 00:15:29 184449.215 Thu Dec 13 00:15:30 184971.058 Thu Dec 13 00:15:31 185036.052 Thu Dec 13 00:15:32 185250.475 Thu Dec 13 00:15:33 184481.319 Thu Dec 13 00:15:34 185225.737 Thu Dec 13 00:15:35 185408.018 Thu Dec 13 00:15:36 185335.764 After ===== kernel profile: % cumulative self self total time samples samples calls 1/call 1/call name 6.33 2813.00 2813.00 29979 0.09 1.01 svc_process 4.66 4883.00 2070.00 2065 1.00 1.00 spin_unlock_irqrestore 4.06 6687.00 1804.00 2182 0.83 1.00 nfsd_ofcache_lookup 3.20 8110.00 1423.00 10932 0.13 1.00 nfsd_dispatch 3.03 9456.00 1346.00 1343 1.00 1.00 nfsd_cache_lookup 2.62 10622.00 1166.00 4645 0.25 1.01 svc_tcp_recvfrom [...] 0.10 42586.00 44.00 74 0.59 1.00 nfsd_choose_ofc <--- HA!! ^^^^ Call rate: nullarbor:~ # pmdumptext nfs3.server.calls ... Thu Dec 13 01:45:28 194677.118 Thu Dec 13 01:45:29 193932.692 Thu Dec 13 01:45:30 194294.364 Thu Dec 13 01:45:31 194971.276 Thu Dec 13 01:45:32 194111.207 Thu Dec 13 01:45:33 194999.635 Thu Dec 13 01:45:34 195312.594 Thu Dec 13 01:45:35 195707.293 Thu Dec 13 01:45:36 194610.353 Thu Dec 13 01:45:37 195913.662 Thu Dec 13 01:45:38 194808.675 i.e. about a 5.3% improvement in call rate. Signed-off-by: Greg Banks <gnb@melbourne.sgi.com> Reviewed-by: David Chinner <dgc@sgi.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-08NFSD: FIDs need to take precedence over UUIDsSteve Dickson1-3/+3
When determining the fsid_type in fh_compose(), the setting of the FID via fsid= export option needs to take precedence over using the UUID device id. Signed-off-by: Steve Dickson <steved@redhat.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06nfsd: update fh_verify descriptionJ. Bruce Fields1-6/+24
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-11-14CRED: Inaugurate COW credentialsDavid Howells1-3/+8
Inaugurate copy-on-write credentials management. This uses RCU to manage the credentials pointer in the task_struct with respect to accesses by other tasks. A process may only modify its own credentials, and so does not need locking to access or modify its own credentials. A mutex (cred_replace_mutex) is added to the task_struct to control the effect of PTRACE_ATTACHED on credential calculations, particularly with respect to execve(). With this patch, the contents of an active credentials struct may not be changed directly; rather a new set of credentials must be prepared, modified and committed using something like the following sequence of events: struct cred *new = prepare_creds(); int ret = blah(new); if (ret < 0) { abort_creds(new); return ret; } return commit_creds(new); There are some exceptions to this rule: the keyrings pointed to by the active credentials may be instantiated - keyrings violate the COW rule as managing COW keyrings is tricky, given that it is possible for a task to directly alter the keys in a keyring in use by another task. To help enforce this, various pointers to sets of credentials, such as those in the task_struct, are declared const. The purpose of this is compile-time discouragement of altering credentials through those pointers. Once a set of credentials has been made public through one of these pointers, it may not be modified, except under special circumstances: (1) Its reference count may incremented and decremented. (2) The keyrings to which it points may be modified, but not replaced. The only safe way to modify anything else is to create a replacement and commit using the functions described in Documentation/credentials.txt (which will be added by a later patch). This patch and the preceding patches have been tested with the LTP SELinux testsuite. This patch makes several logical sets of alteration: (1) execve(). This now prepares and commits credentials in various places in the security code rather than altering the current creds directly. (2) Temporary credential overrides. do_coredump() and sys_faccessat() now prepare their own credentials and temporarily override the ones currently on the acting thread, whilst preventing interference from other threads by holding cred_replace_mutex on the thread being dumped. This will be replaced in a future patch by something that hands down the credentials directly to the functions being called, rather than altering the task's objective credentials. (3) LSM interface. A number of functions have been changed, added or removed: (*) security_capset_check(), ->capset_check() (*) security_capset_set(), ->capset_set() Removed in favour of security_capset(). (*) security_capset(), ->capset() New. This is passed a pointer to the new creds, a pointer to the old creds and the proposed capability sets. It should fill in the new creds or return an error. All pointers, barring the pointer to the new creds, are now const. (*) security_bprm_apply_creds(), ->bprm_apply_creds() Changed; now returns a value, which will cause the process to be killed if it's an error. (*) security_task_alloc(), ->task_alloc_security() Removed in favour of security_prepare_creds(). (*) security_cred_free(), ->cred_free() New. Free security data attached to cred->security. (*) security_prepare_creds(), ->cred_prepare() New. Duplicate any security data attached to cred->security. (*) security_commit_creds(), ->cred_commit() New. Apply any security effects for the upcoming installation of new security by commit_creds(). (*) security_task_post_setuid(), ->task_post_setuid() Removed in favour of security_task_fix_setuid(). (*) security_task_fix_setuid(), ->task_fix_setuid() Fix up the proposed new credentials for setuid(). This is used by cap_set_fix_setuid() to implicitly adjust capabilities in line with setuid() changes. Changes are made to the new credentials, rather than the task itself as in security_task_post_setuid(). (*) security_task_reparent_to_init(), ->task_reparent_to_init() Removed. Instead the task being reparented to init is referred directly to init's credentials. NOTE! This results in the loss of some state: SELinux's osid no longer records the sid of the thread that forked it. (*) security_key_alloc(), ->key_alloc() (*) security_key_permission(), ->key_permission() Changed. These now take cred pointers rather than task pointers to refer to the security context. (4) sys_capset(). This has been simplified and uses less locking. The LSM functions it calls have been merged. (5) reparent_to_kthreadd(). This gives the current thread the same credentials as init by simply using commit_thread() to point that way. (6) __sigqueue_alloc() and switch_uid() __sigqueue_alloc() can't stop the target task from changing its creds beneath it, so this function gets a reference to the currently applicable user_struct which it then passes into the sigqueue struct it returns if successful. switch_uid() is now called from commit_creds(), and possibly should be folded into that. commit_creds() should take care of protecting __sigqueue_alloc(). (7) [sg]et[ug]id() and co and [sg]et_current_groups. The set functions now all use prepare_creds(), commit_creds() and abort_creds() to build and check a new set of credentials before applying it. security_task_set[ug]id() is called inside the prepared section. This guarantees that nothing else will affect the creds until we've finished. The calling of set_dumpable() has been moved into commit_creds(). Much of the functionality of set_user() has been moved into commit_creds(). The get functions all simply access the data directly. (8) security_task_prctl() and cap_task_prctl(). security_task_prctl() has been modified to return -ENOSYS if it doesn't want to handle a function, or otherwise return the return value directly rather than through an argument. Additionally, cap_task_prctl() now prepares a new set of credentials, even if it doesn't end up using it. (9) Keyrings. A number of changes have been made to the keyrings code: (a) switch_uid_keyring(), copy_keys(), exit_keys() and suid_keys() have all been dropped and built in to the credentials functions directly. They may want separating out again later. (b) key_alloc() and search_process_keyrings() now take a cred pointer rather than a task pointer to specify the security context. (c) copy_creds() gives a new thread within the same thread group a new thread keyring if its parent had one, otherwise it discards the thread keyring. (d) The authorisation key now points directly to the credentials to extend the search into rather pointing to the task that carries them. (e) Installing thread, process or session keyrings causes a new set of credentials to be created, even though it's not strictly necessary for process or session keyrings (they're shared). (10) Usermode helper. The usermode helper code now carries a cred struct pointer in its subprocess_info struct instead of a new session keyring pointer. This set of credentials is derived from init_cred and installed on the new process after it has been cloned. call_usermodehelper_setup() allocates the new credentials and call_usermodehelper_freeinfo() discards them if they haven't been used. A special cred function (prepare_usermodeinfo_creds()) is provided specifically for call_usermodehelper_setup() to call. call_usermodehelper_setkeys() adjusts the credentials to sport the supplied keyring as the new session keyring. (11) SELinux. SELinux has a number of changes, in addition to those to support the LSM interface changes mentioned above: (a) selinux_setprocattr() no longer does its check for whether the current ptracer can access processes with the new SID inside the lock that covers getting the ptracer's SID. Whilst this lock ensures that the check is done with the ptracer pinned, the result is only valid until the lock is released, so there's no point doing it inside the lock. (12) is_single_threaded(). This function has been extracted from selinux_setprocattr() and put into a file of its own in the lib/ directory as join_session_keyring() now wants to use it too. The code in SELinux just checked to see whether a task shared mm_structs with other tasks (CLONE_VM), but that isn't good enough. We really want to know if they're part of the same thread group (CLONE_THREAD). (13) nfsd. The NFS server daemon now has to use the COW credentials to set the credentials it is going to use. It really needs to pass the credentials down to the functions it calls, but it can't do that until other patches in this series have been applied. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: James Morris <jmorris@namei.org> Signed-off-by: James Morris <jmorris@namei.org>
2008-11-14CRED: Separate task security context from task_structDavid Howells1-3/+3
Separate the task security context from task_struct. At this point, the security data is temporarily embedded in the task_struct with two pointers pointing to it. Note that the Alpha arch is altered as it refers to (E)UID and (E)GID in entry.S via asm-offsets. With comment fixes Signed-off-by: Marc Dionne <marc.c.dionne@gmail.com> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: James Morris <jmorris@namei.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
2008-09-30nfsd: permit unauthenticated stat of export rootJ. Bruce Fields1-10/+20
RFC 2623 section 2.3.2 permits the server to bypass gss authentication checks for certain operations that a client may perform when mounting. In the case of a client that doesn't have some form of credentials available to it on boot, this allows it to perform the mount unattended. (Presumably real file access won't be needed until a user with credentials logs in.) Being slightly more lenient allows lots of old clients to access krb5-only exports, with the only loss being a small amount of information leaked about the root directory of the export. This affects only v2 and v3; v4 still requires authentication for all access. Thanks to Peter Staubach testing against a Solaris client, which suggesting addition of v3 getattr, to the list, and to Trond for noting that doing so exposes no additional information. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Cc: Peter Staubach <staubach@redhat.com> Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
2008-07-27[PATCH] kill nameidata passing to permission(), rename to inode_permission()Al Viro1-1/+1
Incidentally, the name that gives hundreds of false positives on grep is not a good idea... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-06-30nfsd: fix spurious EACCESS in reconnect_path()Neil Brown1-3/+26
Thanks to Frank Van Maarseveen for the original problem report: "A privileged process on an NFS client which drops privileges after using them to change the current working directory, will experience incorrect EACCES after an NFS server reboot. This problem can also occur after memory pressure on the server, particularly when the client side is quiet for some time." This occurs because the filehandle points to a directory whose parents are no longer in the dentry cache, and we're attempting to reconnect the directory to its parents without adequate permissions to perform lookups in the parent directories. We can therefore fix the problem by acquiring the necessary capabilities before attempting the reconnection. We do this only in the no_subtree_check case, since the documented behavior of the subtree_check export option requires the server to check that the user has lookup permissions on all parents. The subtree_check case still has a problem, since reconnect_path() unnecessarily requires both read and lookup permissions on all parent directories. However, a fix in that case would be more delicate, and use of subtree_check is already discouraged for other reasons. Signed-off-by: Neil Brown <neilb@suse.de> Cc: Frank van Maarseveen <frankvm@frankvm.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-06-23nfsd: rename MAY_ flagsMiklos Szeredi1-1/+1
Rename nfsd_permission() specific MAY_* flags to NFSD_MAY_* to make it clear, that these are not used outside nfsd, and to avoid name and number space conflicts with the VFS. [comment from hch: rename MAY_READ, MAY_WRITE and MAY_EXEC as well] Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-04-24nfsd: move most of fh_verify to separate functionJ. Bruce Fields1-105/+123
Move the code that actually parses the filehandle and looks up the dentry and export to a separate function. This simplifies the reference counting a little and moves fh_verify() a little closer to the kernel ideal of small, minimally-indentended functions. Clean up a few other minor style sins along the way. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Cc: Neil Brown <neilb@suse.de>
2008-03-15nfsd: fix oops on access from high-numbered portsJ. Bruce Fields1-2/+2
This bug was always here, but before my commit 6fa02839bf9412e18e77 ("recheck for secure ports in fh_verify"), it could only be triggered by failure of a kmalloc(). After that commit it could be triggered by a client making a request from a non-reserved port for access to an export marked "secure". (Exports are "secure" by default.) The result is a struct svc_export with a reference count one too low, resulting in likely oopses next time the export is accessed. The reference counting here is not straightforward; a later patch will clean up fh_verify(). Thanks to Lukas Hejtmanek for the bug report and followup. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Cc: Lukas Hejtmanek <xhejtman@ics.muni.cz> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-22Wrap buffers used for rpc debug printks into RPC_IFDEBUGPavel Emelyanov1-1/+1
Sorry for the noise, but here's the v3 of this compilation fix :) There are some places, which declare the char buf[...] on the stack to push it later into dprintk(). Since the dprintk sometimes (if the CONFIG_SYSCTL=n) becomes an empty do { } while (0) stub, these buffers cause gcc to produce appropriate warnings. Wrap these buffers with RPC_IFDEBUG macro, as Trond proposed, to compile them out when not needed. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Acked-by: J. Bruce Fields <bfields@citi.umich.edu> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-15Use struct path in struct svc_exportJan Blunck1-13/+13
I'm embedding struct path into struct svc_export. [akpm@linux-foundation.org: coding-style fixes] [ezk@cs.sunysb.edu: NFSD: fix wrong mnt_writer count in rename] Signed-off-by: Jan Blunck <jblunck@suse.de> Acked-by: J. Bruce Fields <bfields@citi.umich.edu> Acked-by: Christoph Hellwig <hch@infradead.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: Neil Brown <neilb@suse.de> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-02nfsd: move nfsd/auth.h into fs/nfsdJ. Bruce Fields1-0/+1
This header is used only in a few places in fs/nfsd, so there seems to be little point to having it in include/. (Thanks to Robert Day for pointing this out.) Cc: Robert P. J. Day <rpjday@crashcourse.ca> Acked-by: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2007-11-13nfsd4: recheck for secure ports in fh_verifyJ. Bruce Fields1-17/+26
As with commit 7fc90ec93a5eb71f4b08403baf5ba7176b3ec6b1 ("knfsd: nfsd: call nfsd_setuser() on fh_compose(), fix nfsd4 permissions problem") this is a case where we need to redo a security check in fh_verify() even though the filehandle already has an associated dentry--if the filehandle was created by fh_compose() in an earlier operation of the nfsv4 compound, then we may not have done these checks yet. Without this fix it is possible, for example, to traverse from an export without the secure ports requirement to one with it in a single compound, and bypass the secure port check on the new export. While we're here, fix up some minor style problems and change a printk() to a dprintk(), to make it harder for random unprivileged users to spam the logs. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu> Reviewed-By: NeilBrown <neilb@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-22exportfs: add fid typeChristoph Hellwig1-36/+31
This patchset is a medium scale rewrite of the export operations interface. The goal is to make the interface less complex, and easier to understand from the filesystem side, aswell as preparing generic support for exporting of 64bit inode numbers. This touches all nfs exporting filesystems, and I've done testing on all of the filesystems I have here locally (xfs, ext2, ext3, reiserfs, jfs) This patch: Add a structured fid type so that we don't have to pass an array of u32 values around everywhere. It's a union of possible layouts. As a start there's only the u32 array and the traditional 32bit inode format, but there will be more in one of my next patchset when I start to document the various filehandle formats we have in lowlevel filesystems better. Also add an enum that gives the various filehandle types human- readable names. Note: Some people might think the struct containing an anonymous union is ugly, but I didn't want to pass around a raw union type. Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Neil Brown <neilb@suse.de> Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: <linux-ext4@vger.kernel.org> Cc: Dave Kleikamp <shaggy@austin.ibm.com> Cc: Anton Altaparmakov <aia21@cantab.net> Cc: David Chinner <dgc@sgi.com> Cc: Timothy Shimmin <tes@sgi.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Hugh Dickins <hugh@veritas.com> Cc: Chris Mason <mason@suse.com> Cc: Jeff Mahoney <jeffm@suse.com> Cc: "Vladimir V. Saveliev" <vs@namesys.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Mark Fasheh <mark.fasheh@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>