aboutsummaryrefslogtreecommitdiff
path: root/fs/seq_file.c
AgeCommit message (Collapse)Author
2011-12-06fix apparmor dereferencing potentially freed dentry, sanitize __d_path() APIAl Viro
__d_path() API is asking for trouble and in case of apparmor d_namespace_path() getting just that. The root cause is that when __d_path() misses the root it had been told to look for, it stores the location of the most remote ancestor in *root. Without grabbing references. Sure, at the moment of call it had been pinned down by what we have in *path. And if we raced with umount -l, we could have very well stopped at vfsmount/dentry that got freed as soon as prepend_path() dropped vfsmount_lock. It is safe to compare these pointers with pre-existing (and known to be still alive) vfsmount and dentry, as long as all we are asking is "is it the same address?". Dereferencing is not safe and apparmor ended up stepping into that. d_namespace_path() really wants to examine the place where we stopped, even if it's not connected to our namespace. As the result, it looked at ->d_sb->s_magic of a dentry that might've been already freed by that point. All other callers had been careful enough to avoid that, but it's really a bad interface - it invites that kind of trouble. The fix is fairly straightforward, even though it's bigger than I'd like: * prepend_path() root argument becomes const. * __d_path() is never called with NULL/NULL root. It was a kludge to start with. Instead, we have an explicit function - d_absolute_root(). Same as __d_path(), except that it doesn't get root passed and stops where it stops. apparmor and tomoyo are using it. * __d_path() returns NULL on path outside of root. The main caller is show_mountinfo() and that's precisely what we pass root for - to skip those outside chroot jail. Those who don't want that can (and do) use d_path(). * __d_path() root argument becomes const. Everyone agrees, I hope. * apparmor does *NOT* try to use __d_path() or any of its variants when it sees that path->mnt is an internal vfsmount. In that case it's definitely not mounted anywhere and dentry_path() is exactly what we want there. Handling of sysctl()-triggered weirdness is moved to that place. * if apparmor is asked to do pathname relative to chroot jail and __d_path() tells it we it's not in that jail, the sucker just calls d_absolute_path() instead. That's the other remaining caller of __d_path(), BTW. * seq_path_root() does _NOT_ return -ENAMETOOLONG (it's stupid anyway - the normal seq_file logics will take care of growing the buffer and redoing the call of ->show() just fine). However, if it gets path not reachable from root, it returns SEQ_SKIP. The only caller adjusted (i.e. stopped ignoring the return value as it used to do). Reviewed-by: John Johansen <john.johansen@canonical.com> ACKed-by: John Johansen <john.johansen@canonical.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Cc: stable@vger.kernel.org
2010-10-25fs: take dcache_lock inside __d_pathChristoph Hellwig
All callers take dcache_lock just around the call to __d_path, so take the lock into it in preparation of getting rid of dcache_lock. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-09-23fs/seq_file.c: Remove unnecessary casts of private_dataJoe Perches
Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-03-07seq_file: fix new kernel-doc warningsRandy Dunlap
Fix kernel-doc notation in new seq-file functions and correct spelling. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-02-22seq_file: add RCU versions of new hlist/list iterators (v3)stephen hemminger
Many usages of seq_file use RCU protected lists, so non RCU iterators will not work safely. Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2010-02-10seq_file: Add helpers for iteration over a hlistLi Zefan
Some places in kernel need to iterate over a hlist in seq_file, so provide some common helpers. Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-09-24vfs: seq_file: add helpers for data fillingMiklos Szeredi
Add two helpers that allow access to the seq_file's own buffer, but hide the internal details of seq_files. This allows easier implementation of special purpose filling functions. It also cleans up some existing functions which duplicated the seq_file logic. Make these inline functions in seq_file.h, as suggested by Al. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Acked-by: Hugh Dickins <hugh.dickins@tiscali.co.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-09-24seq_file: return a negative error code when seq_path_root() fails.Tetsuo Handa
seq_path_root() is returning a return value of successful __d_path() instead of returning a negative value when mangle_path() failed. This is not a bug so far because nobody is using return value of seq_path_root(). Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-18seq_file: add function to write binary dataPeter Oberparleiter
seq_write() can be used to construct seq_files containing arbitrary data. Required by the gcov-profiling interface to synthesize binary profiling data files. Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Huang Ying <ying.huang@intel.com> Cc: Li Wei <W.Li@Sun.COM> Cc: Michael Ellerman <michaele@au1.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Heiko Carstens <heicars2@linux.vnet.ibm.com> Cc: Martin Schwidefsky <mschwid2@linux.vnet.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: WANG Cong <xiyou.wangcong@gmail.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Jeff Dike <jdike@addtoit.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-30cpumask: fix seq_bitmap_*() functions.Rusty Russell
1) seq_bitmap_list() should take a const. 2) All the seq_bitmap should use cpumask_bits(). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2009-02-18seq_file: properly cope with preadEric Biederman
Currently seq_read assumes that the offset passed to it is always the offset it passed to user space. In the case pread this assumption is broken and we do the wrong thing when presented with pread. To solve this I introduce an offset cache inside of struct seq_file so we know where our logical file position is. Then in seq_read if we try to read from another offset we reset our data structures and attempt to go to the offset user space wanted. [akpm@linux-foundation.org: restore FMODE_PWRITE] [pjt@google.com: seq_open needs its fmode opened up to take advantage of this] Signed-off-by: Eric Biederman <ebiederm@xmission.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Paul Turner <pjt@google.com> Cc: <stable@kernel.org> [2.6.25.x, 2.6.26.x, 2.6.27.x, 2.6.28.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-05seq_file: fix big-enough lseek() + read()Alexey Dobriyan
lseek() further than length of the file will leave stale ->index (second-to-last during iteration). Next seq_read() will not notice that ->f_pos is big enough to return 0, but will print last item as if ->f_pos is pointing to it. Introduced in commit cb510b8172602a66467f3551b4be1911f5a7c8c2 aka "seq_file: more atomicity in traverse()". Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-05seq_file: move traverse so it can be used from seq_readEric Biederman
In 2.6.25 some /proc files were converted to use the seq_file infrastructure. But seq_files do not correctly support pread(), which broke some usersapce applications. To handle pread correctly we can't assume that f_pos is where we left it in seq_read. So move traverse() so that we can eventually use it in seq_read and do thus some day support pread(). Signed-off-by: Eric Biederman <ebiederm@xmission.com> Cc: Paul Turner <pjt@google.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-03Merge branch 'cpus4096-for-linus-3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'cpus4096-for-linus-3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (77 commits) x86: setup_per_cpu_areas() cleanup cpumask: fix compile error when CONFIG_NR_CPUS is not defined cpumask: use alloc_cpumask_var_node where appropriate cpumask: convert shared_cpu_map in acpi_processor* structs to cpumask_var_t x86: use cpumask_var_t in acpi/boot.c x86: cleanup some remaining usages of NR_CPUS where s/b nr_cpu_ids sched: put back some stack hog changes that were undone in kernel/sched.c x86: enable cpus display of kernel_max and offlined cpus ia64: cpumask fix for is_affinity_mask_valid() cpumask: convert RCU implementations, fix xtensa: define __fls mn10300: define __fls m32r: define __fls h8300: define __fls frv: define __fls cris: define __fls cpumask: CONFIG_DISABLE_OBSOLETE_CPUMASK_FUNCTIONS cpumask: zero extra bits in alloc_cpumask_var_node cpumask: replace for_each_cpu_mask_nr with for_each_cpu in kernel/time/ cpumask: convert mm/ ...
2008-12-31expand some comments (d_path / seq_path)Arjan van de Ven
Explain that you really need to use the return value of d_path rather than the buffer you passed into it. Also fix the comment for seq_path(), the function arguments changed recently but the comment hadn't been updated in sync. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-12-30bitmap: fix seq_bitmap and seq_cpumask to take const pointerRusty Russell
Impact: cleanup seq_bitmap just calls bitmap_scnprintf on the bits: that arg can be const. Similarly, seq_cpumask just calls seq_bitmap. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-11-28vfs, seqfile: export mangle_path() generallyIngo Molnar
mangle_path() is trivial enough to make export restrictions on it pointless - so change the export from EXPORT_SYMBOL_GPL to EXPORT_SYMBOL. Signed-off-by: Ingo Molnar <mingo@elte.hu> Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
2008-11-23vfs, seqfile: fix comment style on mangle_pathTörök Edwin
Impact: use standard docbook tags Reported-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Török Edwin <edwintorok@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-11-23vfs, seqfile: make mangle_path() globalTörök Edwin
Impact: expose new VFS API make mangle_path() available, as per the suggestions of Christoph Hellwig and Al Viro: http://lkml.org/lkml/2008/11/4/338 Signed-off-by: Török Edwin <edwintorok@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-20seq_file: add seq_cpumask_list(), seq_nodemask_list()Lai Jiangshan
seq_cpumask_list(), seq_nodemask_list() are very like seq_cpumask(), seq_nodemask(), but they print human readable string. Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Paul Menage <menage@google.com> Cc: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20seq_file: don't call bitmap_scnprintf_len()Lai Jiangshan
"m->count + len < m->size" is true commonly, so bitmap_scnprintf() is commonly called. this fix saves a call to bitmap_scnprintf_len(). Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Paul Menage <menage@google.com> Cc: Paul Jackson <pj@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-08-25[PATCH] deal with the first call of ->show() generating no outputAl Viro
seq_read() has a subtle bug - we want the first loop there to go until at least one *non-empty* record had fit entirely into buffer. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-08-12seq_file: add seq_cpumask(), seq_nodemask()Alexey Dobriyan
Short enough reads from /proc/irq/*/smp_affinity return -EINVAL for no good reason. This became noticed with NR_CPUS=4096 patches, when length of printed representation of cpumask becase 1152, but cat(1) continued to read with 1024-byte chunks. bitmap_scnprintf() in good faith fills buffer, returns 1023, check returns -EINVAL. Fix it by switching to seq_file, so handler will just fill buffer and doesn't care about offsets, length, filling EOF and all this crap. For that add seq_bitmap(), and wrappers around it -- seq_cpumask() and seq_nodemask(). Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Reviewed-by: Paul Jackson <pj@sgi.com> Cc: Mike Travis <travis@sgi.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-23[patch 2/7] vfs: mountinfo: add seq_file_root()Miklos Szeredi
Add a new function: seq_file_root() This is similar to seq_path(), but calculates the path relative to the given root, instead of current->fs->root. If the path was unreachable from root, then modify the root parameter to reflect this. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-23[patch 1/7] vfs: mountinfo: add dentry_path()Ram Pai
[mszeredi@suse.cz] split big patch into managable chunks Add the following functions: dentry_path() seq_dentry() These are similar to d_path() and seq_path(). But instead of calculating the path within a mount namespace, they calculate the path from the root of the filesystem to a given dentry, ignoring mounts completely. Signed-off-by: Ram Pai <linuxram@us.ibm.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-22Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: [PATCH] get rid of __exit_files(), __exit_fs() and __put_fs_struct() [PATCH] proc_readfd_common() race fix [PATCH] double-free of inode on alloc_file() failure exit in create_write_pipe() [PATCH] teach seq_file to discard entries [PATCH] umount_tree() will unhash everything itself [PATCH] get rid of more nameidata passing in namespace.c [PATCH] switch a bunch of LSM hooks from nameidata to path [PATCH] lock exclusively in collect_mounts() and drop_collected_mounts() [PATCH] move a bunch of declarations to fs/internal.h
2008-04-22fs: use loff_t type instead of long longDavid Sterba
Use offset type consistently. Signed-off-by: David Sterba <dsterba@suse.cz> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-21[PATCH] teach seq_file to discard entriesAl Viro
Allow ->show() return SEQ_SKIP; that will discard all output from that element and move on. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-02-14d_path: Make d_path() use a struct pathJan Blunck
d_path() is used on a <dentry,vfsmount> pair. Lets use a struct path to reflect this. [akpm@linux-foundation.org: fix build in mm/memory.c] Signed-off-by: Jan Blunck <jblunck@suse.de> Acked-by: Bryan Wu <bryan.wu@analog.com> 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: Michael Halcrow <mhalcrow@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-14d_path: Make seq_path() use a struct path argumentJan Blunck
seq_path() is always called with a dentry and a vfsmount from a struct path. Make seq_path() take it directly as an argument. Signed-off-by: Jan Blunck <jblunck@suse.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-10[FS] seq_file: Introduce the seq_open_private()Pavel Emelyanov
This function allocates the zeroed chunk of memory and call seq_open(). The __seq_open_private() helper returns the allocated memory to make it possible for the caller to initialize it. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-16seq_file: more atomicity in traverse()Alexey Dobriyan
Original problem: in some circumstances seq_file interface can present infinite proc file to the following script when normally said proc file is finite: while read line; do [do something with $line] done </proc/$FILE bash, to implement such loop does essentially read(0, buf, 128); [find \n] lseek(0, -difference, SEEK_CUR); Consider, proc file prints list of objects each of them consists of many lines, each line is shorter than 128 bytes. Two objects in list, with ->index'es being 0 and 1. Current one is 1, as bash prints second object line by line. Imagine first object being removed right before lseek(). traverse() will be called, because there is negative offset. traverse() will reset ->index to 0 (!). traverse() will call ->next() and get NULL in any usual iterate-over-list code using list_for_each_entry_continue() and such. There is one object in list now after all... traverse() will return 0, lseek() will update file position and pretend everything is OK. So, what we have now: ->f_pos points to place where second object will be printed, but ->index is 0. seq_read() instead of returning EOF, will start printing first line of first object every time it's called, until enough objects are added to ->f_pos return in bounds. Fix is to update ->index only after we're sure we saw enough objects down the road. Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16mutex_unlock() later in seq_lseek()Alexey Dobriyan
All manipulations with struct seq_file::version are done under struct seq_file::lock except one introduced in commit d6b7a781c51c91dd054e5c437885205592faac21 aka "[PATCH] Speed up /proc/pid/maps" Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-10Make common helpers for seq_files that work with list_headsPavel Emelianov
Many places in kernel use seq_file API to iterate over a regular list_head. The code for such iteration is identical in all the places, so it's worth introducing a common helpers. This makes code about 300 lines smaller: The first version of this patch made the helper functions static inline in the seq_file.h header. This patch moves them to the fs/seq_file.c as Andrew proposed. The vmlinux .text section sizes are as follows: 2.6.22-rc1-mm1: 0x001794d5 with the previous version: 0x00179505 with this patch: 0x00179135 The config file used was make allnoconfig with the "y" inclusion of all the possible options to make the files modified by the patch compile plus drivers I have on the test node. This patch: Many places in kernel use seq_file API to iterate over a regular list_head. The code for such iteration is identical in all the places, so it's worth introducing a common helpers. Signed-off-by: Pavel Emelianov <xemul@openvz.org> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-12-08[PATCH] VFS: change struct file to use struct pathJosef "Jeff" Sipek
This patch changes struct file to use struct path instead of having independent pointers to struct dentry and struct vfsmount, and converts all users of f_{dentry,vfsmnt} in fs/ to use f_path.{dentry,mnt}. Additionally, it adds two #define's to make the transition easier for users of the f_dentry and f_vfsmnt. Signed-off-by: Josef "Jeff" Sipek <jsipek@cs.sunysb.edu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07[PATCH] struct seq_operations and struct file_operations constificationHelge Deller
- move some file_operations structs into the .rodata section - move static strings from policy_types[] array into the .rodata section - fix generic seq_operations usages, so that those structs may be defined as "const" as well [akpm@osdl.org: couple of fixes] Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-23[PATCH] sem2mutex: fs/seq_file.cIngo Molnar
Semaphore to mutex conversion. The conversion was generated via scripts, and the result was validated automatically via a script as well. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07[PATCH] allow callers of seq_open do allocation themselvesAl Viro
Allow caller of seq_open() to kmalloc() seq_file + whatever else they want and set ->private_data to it. seq_open() will then abstain from doing allocation itself. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-05-01[PATCH] DocBook: fix some descriptionsMartin Waitz
Some KernelDoc descriptions are updated to match the current code. No code changes. Signed-off-by: Martin Waitz <tali@admingilde.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!