summaryrefslogtreecommitdiff
path: root/fs/proc/base.c
AgeCommit message (Collapse)Author
2015-01-08userns: Add a knob to disable setgroups on a per user namespace basisEric W. Biederman
commit 9cc46516ddf497ea16e8d7cb986ae03a0f6b92f8 upstream. - Expose the knob to user space through a proc file /proc/<pid>/setgroups A value of "deny" means the setgroups system call is disabled in the current processes user namespace and can not be enabled in the future in this user namespace. A value of "allow" means the segtoups system call is enabled. - Descendant user namespaces inherit the value of setgroups from their parents. - A proc file is used (instead of a sysctl) as sysctls currently do not allow checking the permissions at open time. - Writing to the proc file is restricted to before the gid_map for the user namespace is set. This ensures that disabling setgroups at a user namespace level will never remove the ability to call setgroups from a process that already has that ability. A process may opt in to the setgroups disable for itself by creating, entering and configuring a user namespace or by calling setns on an existing user namespace with setgroups disabled. Processes without privileges already can not call setgroups so this is a noop. Prodcess with privilege become processes without privilege when entering a user namespace and as with any other path to dropping privilege they would not have the ability to call setgroups. So this remains within the bounds of what is possible without a knob to disable setgroups permanently in a user namespace. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-03-10fs/proc/base.c: fix GPF in /proc/$PID/map_filesArtem Fetishev
The expected logic of proc_map_files_get_link() is either to return 0 and initialize 'path' or return an error and leave 'path' uninitialized. By the time dname_to_vma_addr() returns 0 the corresponding vma may have already be gone. In this case the path is not initialized but the return value is still 0. This results in 'general protection fault' inside d_path(). Steps to reproduce: CONFIG_CHECKPOINT_RESTORE=y fd = open(...); while (1) { mmap(fd, ...); munmap(fd, ...); } ls -la /proc/$PID/map_files Addresses https://bugzilla.kernel.org/show_bug.cgi?id=68991 Signed-off-by: Artem Fetishev <artem_fetishev@epam.com> Signed-off-by: Aleksandr Terekhov <aleksandr_terekhov@epam.com> Reported-by: <wiebittewas@gmail.com> Acked-by: Pavel Emelyanov <xemul@parallels.com> Acked-by: Cyrill Gorcunov <gorcunov@openvz.org> Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-23proc: fix ->f_pos overflows in first_tid()Oleg Nesterov
1. proc_task_readdir()->first_tid() path truncates f_pos to int, this is wrong even on 64bit. We could check that f_pos < PID_MAX or even INT_MAX in proc_task_readdir(), but this patch simply checks the potential overflow in first_tid(), this check is nop on 64bit. We do not care if it was negative and the new unsigned value is huge, all we need to ensure is that we never wrongly return !NULL. 2. Remove the 2nd "nr != 0" check before get_nr_threads(), nr_threads == 0 is not distinguishable from !pid_task() above. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Sameer Nanda <snanda@chromium.org> Cc: Sergey Dyasly <dserrg@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-23proc: don't (ab)use ->group_leader in proc_task_readdir() pathsOleg Nesterov
proc_task_readdir() does not really need "leader", first_tid() has to revalidate it anyway. Just pass proc_pid(inode) to first_tid() instead, it can do pid_task(PIDTYPE_PID) itself and read ->group_leader only if necessary. The patch also extracts the "inode is dead" code from pid_delete_dentry(dentry) into the new trivial helper, proc_inode_is_dead(inode), proc_task_readdir() uses it to return -ENOENT if this dir was removed. This is a bit racy, but the race is very inlikely and the getdents() after openndir() can see the empty "." + ".." dir only once. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Sameer Nanda <snanda@chromium.org> Cc: Sergey Dyasly <dserrg@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-23proc: change first_tid() to use while_each_thread() rather than next_thread()Oleg Nesterov
Rerwrite the main loop to use while_each_thread() instead of next_thread(). We are going to fix or replace while_each_thread(), next_thread() should be avoided whenever possible. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Sameer Nanda <snanda@chromium.org> Cc: Sergey Dyasly <dserrg@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-01-23proc: fix the potential use-after-free in first_tid()Oleg Nesterov
proc_task_readdir() verifies that the result of get_proc_task() is pid_alive() and thus its ->group_leader is fine too. However this is not necessarily true after rcu_read_unlock(), we need to recheck this again after first_tid() does rcu_read_lock(). Otherwise leader->thread_group.next (used by next_thread()) can be invalid if the rcu grace period expires in between. The race is subtle and unlikely, but still it is possible afaics. To simplify lets ignore the "likely" case when tid != 0, f_version can be cleared by proc_task_operations->llseek(). Suppose we have a main thread M and its subthread T. Suppose that f_pos == 3, iow first_tid() should return T. Now suppose that the following happens between rcu_read_unlock() and rcu_read_lock(): 1. T execs and becomes the new leader. This removes M from ->thread_group but next_thread(M) is still T. 2. T creates another thread X which does exec as well, T goes away. 3. X creates another subthread, this increments nr_threads. 4. first_tid() does next_thread(M) and returns the already dead T. Note also that we need 2. and 3. only because of get_nr_threads() check, and this check was supposed to be optimization only. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Sameer Nanda <snanda@chromium.org> Cc: Sergey Dyasly <dserrg@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-05audit: allow unsetting the loginuid (with priv)Eric Paris
If a task has CAP_AUDIT_CONTROL allow that task to unset their loginuid. This would allow a child of that task to set their loginuid without CAP_AUDIT_CONTROL. Thus when launching a new login daemon, a priviledged helper would be able to unset the loginuid and then the daemon, which may be malicious user facing, do not need priv to function correctly. Signed-off-by: Eric Paris <eparis@redhat.com> Signed-off-by: Richard Guy Briggs <rgb@redhat.com> Signed-off-by: Eric Paris <eparis@redhat.com>
2013-06-29proc_fill_cache(): clean up, get rid of pointless find_inode_number() useAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29proc_fill_cache(): just make instantiate_t return intAl Viro
all instances always return ERR_PTR(-E...) or NULL, anyway Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29proc_pid_readdir(): stop wanking with proc_fill_cache() for /proc/selfAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29proc_fill_cache(): kill pointless checkAl Viro
we'd just checked that child->d_inode is non-NULL, for fuck sake! Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29[readdir] convert procfsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-05-28posix-timers: Show clock ID in proc filePavel Tikhomirov
Expand information about posix-timers in /proc/<pid>/timers by adding info about clock, with which the timer was created. I.e. in the forth line of timer info after "notify:" line go "ClockID: <clock_id>". Signed-off-by: Pavel Tikhomirov <snorcht@gmail.com> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Matthew Helsley <matt.helsley@gmail.com> Cc: Pavel Emelyanov <xemul@parallels.com> Link: http://lkml.kernel.org/r/1368742323-46949-2-git-send-email-snorcht@gmail.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-05-01Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull VFS updates from Al Viro, Misc cleanups all over the place, mainly wrt /proc interfaces (switch create_proc_entry to proc_create(), get rid of the deprecated create_proc_read_entry() in favor of using proc_create_data() and seq_file etc). 7kloc removed. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (204 commits) don't bother with deferred freeing of fdtables proc: Move non-public stuff from linux/proc_fs.h to fs/proc/internal.h proc: Make the PROC_I() and PDE() macros internal to procfs proc: Supply a function to remove a proc entry by PDE take cgroup_open() and cpuset_open() to fs/proc/base.c ppc: Clean up scanlog ppc: Clean up rtas_flash driver somewhat hostap: proc: Use remove_proc_subtree() drm: proc: Use remove_proc_subtree() drm: proc: Use minor->index to label things, not PDE->name drm: Constify drm_proc_list[] zoran: Don't print proc_dir_entry data in debug reiserfs: Don't access the proc_dir_entry in r_open(), r_start() r_show() proc: Supply an accessor for getting the data from a PDE's parent airo: Use remove_proc_subtree() rtl8192u: Don't need to save device proc dir PDE rtl8187se: Use a dir under /proc/net/r8180/ proc: Add proc_mkdir_data() proc: Move some bits from linux/proc_fs.h to linux/{of.h,signal.h,tty.h} proc: Move PDE_NET() to fs/proc/proc_net.c ...
2013-05-01take cgroup_open() and cpuset_open() to fs/proc/base.cAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-05-01proc: Uninline pid_delete_dentry()David Howells
Uninline pid_delete_dentry() as it's only used by three function pointers. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-04-30fs, proc: truncate /proc/pid/comm writes to first TASK_COMM_LEN bytesDavid Rientjes
Currently, a write to a procfs file will return the number of bytes successfully written. If the actual string is longer than this, the remainder of the string will not be be written and userspace will complete the operation by issuing additional write()s. Hence $ echo -n "abcdefghijklmnopqrs" > /proc/self/comm results in $ cat /proc/$$/comm pqrs since the final four bytes were written with a second write() since TASK_COMM_LEN == 16. This is obviously an undesired result and not equivalent to prctl(PR_SET_NAME). The implementation should not need to know the definition of TASK_COMM_LEN. This patch truncates the string to the first TASK_COMM_LEN bytes and returns the bytes written as the length of the string written so the second write() is suppressed. $ cat /proc/$$/comm abcdefghijklmno Signed-off-by: David Rientjes <rientjes@google.com> Acked-by: John Stultz <john.stultz@linaro.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-17posix-timers: Show sigevent info in proc filePavel Emelyanov
Previous patch added proc file to list posix timers created by task. Expand the information provided in this file by adding info about notification method, with which timers were created. I.e. after the "ID:" line there go 1. "signal:" line, that shows signal number and sigval bits; 2. "notify:" line, that shows the timer notification method. Thus the timer entry would looke like this: ID: 123 signal: 14/0000000000b005d0 notify: signal/pid.732 This information is enough to understand how timer_create() was called for each particular timer. Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Matthew Helsley <matt.helsley@gmail.com> Link: http://lkml.kernel.org/r/513DA024.80404@parallels.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-04-17posix-timers: Introduce /proc/PID/timers filePavel Emelyanov
Currently kernel doesn't provide any API for getting info about what posix timers are configured by processes. It's implied, that a process which configured some timers, knows what it did. However, for external tools it's impossible to get this information. In particular, this is critical for checkpoint-restore project to have this info. Introduce a per-pid proc file with information about posix timers. Since these timers are shared between threads, this file is present on tgid level only, no such thing in tid subdirs. The file format is expected to be the "/proc/<pid>/smaps"-like, i.e. each timer will occupy seveal lines to allow for future extending. Each new timer entry starts with the ID: <number> line which is added by this patch. Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Matthew Helsley <matt.helsley@gmail.com> Link: http://lkml.kernel.org/r/513DA00D.6070009@parallels.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2013-04-09procfs: switch /proc/self away from proc_dir_entryAl Viro
Just have it pinned in dcache all along and let procfs ->kill_sb() drop it before kill_anon_super(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-27fs/proc: clean up printksAndrew Morton
- use pr_foo() throughout - remove a couple of duplicated KERN_WARNINGs, via WARN(KERN_WARNING "...") - nuke a few warnings which I've never seen happen, ever. Cc: Joe Perches <joe@perches.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-26fs: change return values from -EACCES to -EPERMZhao Hongjiang
According to SUSv3: [EACCES] Permission denied. An attempt was made to access a file in a way forbidden by its file access permissions. [EPERM] Operation not permitted. An attempt was made to perform an operation limited to processes with appropriate privileges or to the owner of a file or other resource. So -EPERM should be returned if capability checks fails. Strictly speaking this is an API change since the error code user sees is altered. Signed-off-by: Zhao Hongjiang <zhaohongjiang@huawei.com> Acked-by: Jan Kara <jack@suse.cz> Acked-by: Steven Whitehouse <swhiteho@redhat.com> Acked-by: Ian Kent <raven@themaw.net> 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>
2013-02-26d_hash_and_lookup(): export, switch open-coded instancesAl Viro
* calling conventions change - ERR_PTR() is returned on ->d_hash() errors; NULL is just for dcache miss now. * exported, open-coded instances in ncpfs and cifs converted. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-22new helper: file_inode(file)Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20procfs: drop vmtruncateMarco Stornelli
Removed vmtruncate Signed-off-by: Marco Stornelli <marco.stornelli@gmail.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-17Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace Pull user namespace changes from Eric Biederman: "While small this set of changes is very significant with respect to containers in general and user namespaces in particular. The user space interface is now complete. This set of changes adds support for unprivileged users to create user namespaces and as a user namespace root to create other namespaces. The tyranny of supporting suid root preventing unprivileged users from using cool new kernel features is broken. This set of changes completes the work on setns, adding support for the pid, user, mount namespaces. This set of changes includes a bunch of basic pid namespace cleanups/simplifications. Of particular significance is the rework of the pid namespace cleanup so it no longer requires sending out tendrils into all kinds of unexpected cleanup paths for operation. At least one case of broken error handling is fixed by this cleanup. The files under /proc/<pid>/ns/ have been converted from regular files to magic symlinks which prevents incorrect caching by the VFS, ensuring the files always refer to the namespace the process is currently using and ensuring that the ptrace_mayaccess permission checks are always applied. The files under /proc/<pid>/ns/ have been given stable inode numbers so it is now possible to see if different processes share the same namespaces. Through the David Miller's net tree are changes to relax many of the permission checks in the networking stack to allowing the user namespace root to usefully use the networking stack. Similar changes for the mount namespace and the pid namespace are coming through my tree. Two small changes to add user namespace support were commited here adn in David Miller's -net tree so that I could complete the work on the /proc/<pid>/ns/ files in this tree. Work remains to make it safe to build user namespaces and 9p, afs, ceph, cifs, coda, gfs2, ncpfs, nfs, nfsd, ocfs2, and xfs so the Kconfig guard remains in place preventing that user namespaces from being built when any of those filesystems are enabled. Future design work remains to allow root users outside of the initial user namespace to mount more than just /proc and /sys." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (38 commits) proc: Usable inode numbers for the namespace file descriptors. proc: Fix the namespace inode permission checks. proc: Generalize proc inode allocation userns: Allow unprivilged mounts of proc and sysfs userns: For /proc/self/{uid,gid}_map derive the lower userns from the struct file procfs: Print task uids and gids in the userns that opened the proc file userns: Implement unshare of the user namespace userns: Implent proc namespace operations userns: Kill task_user_ns userns: Make create_new_namespaces take a user_ns parameter userns: Allow unprivileged use of setns. userns: Allow unprivileged users to create new namespaces userns: Allow setting a userns mapping to your current uid. userns: Allow chown and setgid preservation userns: Allow unprivileged users to create user namespaces. userns: Ignore suid and sgid on binaries if the uid or gid can not be mapped userns: fix return value on mntns_install() failure vfs: Allow unprivileged manipulation of the mount namespace. vfs: Only support slave subtrees across different user namespaces vfs: Add a user namespace reference from struct mnt_namespace ...
2012-12-11mm, oom: change type of oom_score_adj to shortDavid Rientjes
The maximum oom_score_adj is 1000 and the minimum oom_score_adj is -1000, so this range can be represented by the signed short type with no functional change. The extra space this frees up in struct signal_struct will be used for per-thread oom kill flags in the next patch. Signed-off-by: David Rientjes <rientjes@google.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Reviewed-by: Michal Hocko <mhocko@suse.cz> Cc: Anton Vorontsov <anton.vorontsov@linaro.org> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-11-26proc: check vma->vm_file before dereferencingStanislav Kinsbursky
Commit 7b540d0646ce ("proc_map_files_readdir(): don't bother with grabbing files") switched proc_map_files_readdir() to use @f_mode directly instead of grabbing @file reference, but same time the test for @vm_file presence was lost leading to nil dereference. The patch brings the test back. The all proc_map_files feature is CONFIG_CHECKPOINT_RESTORE wrapped (which is set to 'n' by default) so the bug doesn't affect regular kernels. The regression is 3.7-rc1 only as far as I can tell. [gorcunov@openvz.org: provided changelog] Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com> Acked-by: Cyrill Gorcunov <gorcunov@openvz.org> 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>
2012-11-19pidns: Make the pidns proc mount/umount logic obvious.Eric W. Biederman
Track the number of pids in the proc hash table. When the number of pids goes to 0 schedule work to unmount the kernel mount of proc. Move the mount of proc into alloc_pid when we allocate the pid for init. Remove the surprising calls of pid_ns_release proc in fork and proc_flush_task. Those code paths really shouldn't know about proc namespace implementation details and people have demonstrated several times that finding and understanding those code paths is difficult and non-obvious. Because of the call path detach pid is alwasy called with the rtnl_lock held free_pid is not allowed to sleep, so the work to unmounting proc is moved to a work queue. This has the side benefit of not blocking the entire world waiting for the unnecessary rcu_barrier in deactivate_locked_super. In the process of making the code clear and obvious this fixes a bug reported by Gao feng <gaofeng@cn.fujitsu.com> where we would leak a mount of proc during clone(CLONE_NEWPID|CLONE_NEWNET) if copy_pid_ns succeeded and copy_net_ns failed. Acked-by: "Serge E. Hallyn" <serge@hallyn.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2012-11-19procfs: Don't cache a pid in the root inode.Eric W. Biederman
Now that we have s_fs_info pointing to our pid namespace the original reason for the proc root inode having a struct pid is gone. Caching a pid in the root inode has led to some complicated code. Now that we don't need the struct pid, just remove it. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-11-19procfs: Use the proc generic infrastructure for proc/self.Eric W. Biederman
I had visions at one point of splitting proc into two filesystems. If that had happened proc/self being the the part of proc that actually deals with pids would have been a nice cleanup. As it is proc/self requires a lot of unnecessary infrastructure for a single file. The only user visible change is that a mounted /proc for a pid namespace that is dead now shows a broken proc symlink, instead of being completely invisible. I don't think anyone will notice or care. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-11-16mm, oom: reintroduce /proc/pid/oom_adjDavid Rientjes
This is mostly a revert of 01dc52ebdf47 ("oom: remove deprecated oom_adj") from Davidlohr Bueso. It reintroduces /proc/pid/oom_adj for backwards compatibility with earlier kernels. It simply scales the value linearly when /proc/pid/oom_score_adj is written. The major difference is that its scheduled removal is no longer included in Documentation/feature-removal-schedule.txt. We do warn users with a single printk, though, to suggest the more powerful and supported /proc/pid/oom_score_adj interface. Reported-by: Artem S. Tashkinov <t.artem@lycos.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-12procfs: don't need a PATH_MAX allocation to hold a string representation of ↵Jeff Layton
an int Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-09oom: remove deprecated oom_adjDavidlohr Bueso
The deprecated /proc/<pid>/oom_adj is scheduled for removal this month. Signed-off-by: Davidlohr Bueso <dave@gnu.org> Acked-by: David Rientjes <rientjes@google.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-02Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs update from Al Viro: - big one - consolidation of descriptor-related logics; almost all of that is moved to fs/file.c (BTW, I'm seriously tempted to rename the result to fd.c. As it is, we have a situation when file_table.c is about handling of struct file and file.c is about handling of descriptor tables; the reasons are historical - file_table.c used to be about a static array of struct file we used to have way back). A lot of stray ends got cleaned up and converted to saner primitives, disgusting mess in android/binder.c is still disgusting, but at least doesn't poke so much in descriptor table guts anymore. A bunch of relatively minor races got fixed in process, plus an ext4 struct file leak. - related thing - fget_light() partially unuglified; see fdget() in there (and yes, it generates the code as good as we used to have). - also related - bits of Cyrill's procfs stuff that got entangled into that work; _not_ all of it, just the initial move to fs/proc/fd.c and switch of fdinfo to seq_file. - Alex's fs/coredump.c spiltoff - the same story, had been easier to take that commit than mess with conflicts. The rest is a separate pile, this was just a mechanical code movement. - a few misc patches all over the place. Not all for this cycle, there'll be more (and quite a few currently sit in akpm's tree)." Fix up trivial conflicts in the android binder driver, and some fairly simple conflicts due to two different changes to the sock_alloc_file() interface ("take descriptor handling from sock_alloc_file() to callers" vs "net: Providing protocol type via system.sockprotoname xattr of /proc/PID/fd entries" adding a dentry name to the socket) * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (72 commits) MAX_LFS_FILESIZE should be a loff_t compat: fs: Generic compat_sys_sendfile implementation fs: push rcu_barrier() from deactivate_locked_super() to filesystems btrfs: reada_extent doesn't need kref for refcount coredump: move core dump functionality into its own file coredump: prevent double-free on an error path in core dumper usb/gadget: fix misannotations fcntl: fix misannotations ceph: don't abuse d_delete() on failure exits hypfs: ->d_parent is never NULL or negative vfs: delete surplus inode NULL check switch simple cases of fget_light to fdget new helpers: fdget()/fdput() switch o2hb_region_dev_write() to fget_light() proc_map_files_readdir(): don't bother with grabbing files make get_file() return its argument vhost_set_vring(): turn pollstart/pollstop into bool switch prctl_set_mm_exe_file() to fget_light() switch xfs_find_handle() to fget_light() switch xfs_swapext() to fget_light() ...
2012-09-26proc_map_files_readdir(): don't bother with grabbing filesAl Viro
all we need is their ->f_mode, so just collect _that_ Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-26make get_file() return its argumentAl Viro
simplifies a bunch of callers... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-26procfs: Move /proc/pid/fd[info] handling code to fd.[ch]Cyrill Gorcunov
This patch prepares the ground for further extension of /proc/pid/fd[info] handling code by moving fdinfo handling code into fs/proc/fd.c. I think such move makes both fs/proc/base.c and fs/proc/fd.c easier to read. Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Acked-by: Pavel Emelyanov <xemul@parallels.com> CC: Al Viro <viro@ZenIV.linux.org.uk> CC: Alexey Dobriyan <adobriyan@gmail.com> CC: Andrew Morton <akpm@linux-foundation.org> CC: James Bottomley <jbottomley@parallels.com> CC: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> CC: Alexey Dobriyan <adobriyan@gmail.com> CC: Matthew Helsley <matt.helsley@gmail.com> CC: "J. Bruce Fields" <bfields@fieldses.org> CC: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-18userns: Add kprojid_t and associated infrastructure in projid.hEric W. Biederman
Implement kprojid_t a cousin of the kuid_t and kgid_t. The per user namespace mapping of project id values can be set with /proc/<pid>/projid_map. A full compliment of helpers is provided: make_kprojid, from_kprojid, from_kprojid_munged, kporjid_has_mapping, projid_valid, projid_eq, projid_eq, projid_lt. Project identifiers are part of the generic disk quota interface, although it appears only xfs implements project identifiers currently. The xfs code allows anyone who has permission to set the project identifier on a file to use any project identifier so when setting up the user namespace project identifier mappings I do not require a capability. Cc: Dave Chinner <david@fromorbit.com> Cc: Jan Kara <jack@suse.cz> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2012-09-17userns: Convert the audit loginuid to be a kuidEric W. Biederman
Always store audit loginuids in type kuid_t. Print loginuids by converting them into uids in the appropriate user namespace, and then printing the resulting uid. Modify audit_get_loginuid to return a kuid_t. Modify audit_set_loginuid to take a kuid_t. Modify /proc/<pid>/loginuid on read to convert the loginuid into the user namespace of the opener of the file. Modify /proc/<pid>/loginud on write to convert the loginuid rom the user namespace of the opener of the file. Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Eric Paris <eparis@redhat.com> Cc: Paul Moore <paul@paul-moore.com> ? Cc: David Miller <davem@davemloft.net> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-07-30proc: do not allow negative offsets on /proc/<pid>/environDjalal Harouni
__mem_open() which is called by both /proc/<pid>/environ and /proc/<pid>/mem ->open() handlers will allow the use of negative offsets. /proc/<pid>/mem has negative offsets but not /proc/<pid>/environ. Clean this by moving the 'force FMODE_UNSIGNED_OFFSET flag' to mem_open() to allow negative offsets only on /proc/<pid>/mem. Signed-off-by: Djalal Harouni <tixxdz@opendz.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Brad Spengler <spender@grsecurity.net> Acked-by: Kees Cook <keescook@chromium.org> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-30proc: environ_read() make sure offset points to environment address rangeDjalal Harouni
Currently the following offset and environment address range check in environ_read() of /proc/<pid>/environ is buggy: int this_len = mm->env_end - (mm->env_start + src); if (this_len <= 0) break; Large or negative offsets on /proc/<pid>/environ converted to 'unsigned long' may pass this check since '(mm->env_start + src)' can overflow and 'this_len' will be positive. This can turn /proc/<pid>/environ to act like /proc/<pid>/mem since (mm->env_start + src) will point and read from another VMA. There are two fixes here plus some code cleaning: 1) Fix the overflow by checking if the offset that was converted to unsigned long will always point to the [mm->env_start, mm->env_end] address range. 2) Remove the truncation that was made to the result of the check, storing the result in 'int this_len' will alter its value and we can not depend on it. For kernels that have commit b409e578d ("proc: clean up /proc/<pid>/environ handling") which adds the appropriate ptrace check and saves the 'mm' at ->open() time, this is not a security issue. This patch is taken from the grsecurity patch since it was just made available. Signed-off-by: Djalal Harouni <tixxdz@opendz.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Brad Spengler <spender@grsecurity.net> Acked-by: Kees Cook <keescook@chromium.org> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-14fs: add nd_jump_linkChristoph Hellwig
Add a helper that abstracts out the jump to an already parsed struct path from ->follow_link operation from procfs. Not only does this clean up the code by moving the two sides of this game into a single helper, but it also prepares for making struct nameidata private to namei.c Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14fs: move path_put on failure out of ->follow_linkChristoph Hellwig
Currently the non-nd_set_link based versions of ->follow_link are expected to do a path_put(&nd->path) on failure. This calling convention is unexpected, undocumented and doesn't match what the nd_set_link-based instances do. Move the path_put out of the only non-nd_set_link based ->follow_link instance into the caller. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14stop passing nameidata to ->lookup()Al Viro
Just the flags; only NFS cares even about that, but there are legitimate uses for such argument. And getting rid of that completely would require splitting ->lookup() into a couple of methods (at least), so let's leave that alone for now... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14stop passing nameidata * to ->d_revalidate()Al Viro
Just the lookup flags. Die, bastard, die... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-04vfs: Fix /proc/<tid>/fdinfo/<fd> file handlingLinus Torvalds
Cyrill Gorcunov reports that I broke the fdinfo files with commit 30a08bf2d31d ("proc: move fd symlink i_mode calculations into tid_fd_revalidate()"), and he's quite right. The tid_fd_revalidate() function is not just used for the <tid>/fd symlinks, it's also used for the <tid>/fdinfo/<fd> files, and the permission model for those are different. So do the dynamic symlink permission handling just for symlinks, making the fdinfo files once more appear as the proper regular files they are. Of course, Al Viro argued (probably correctly) that we shouldn't do the symlink permission games at all, and make the symlinks always just be the normal 'lrwxrwxrwx'. That would have avoided this issue too, but since somebody noticed that the permissions had changed (which was the reason for that original commit 30a08bf2d31d in the first place), people do apparently use this feature. [ Basically, you can use the symlink permission data as a cheap "fdinfo" replacement, since you see whether the file is open for reading and/or writing by just looking at st_mode of the symlink. So the feature does make sense, even if the pain it has caused means we probably shouldn't have done it to begin with. ] Reported-and-tested-by: Cyrill Gorcunov <gorcunov@openvz.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31fs, proc: introduce /proc/<pid>/task/<tid>/children entryCyrill Gorcunov
When we do checkpoint of a task we need to know the list of children the task, has but there is no easy and fast way to generate reverse parent->children chain from arbitrary <pid> (while a parent pid is provided in "PPid" field of /proc/<pid>/status). So instead of walking over all pids in the system (creating one big process tree in memory, just to figure out which children a task has) -- we add explicit /proc/<pid>/task/<tid>/children entry, because the kernel already has this kind of information but it is not yet exported. This is a first level children, not the whole process tree. Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Serge Hallyn <serge.hallyn@canonical.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31proc: pass "fd" by value in /proc/*/{fd,fdinfo} codeAlexey Dobriyan
Pass "fd" directly, not via pointer -- one less memory read. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31proc: don't do dummy rcu_read_lock/rcu_read_unlock on error pathAlexey Dobriyan
rcu_read_lock()/rcu_read_unlock() is nop for TINY_RCU, but is not a nop for, say, PREEMPT_RCU. proc_fill_cache() is called without RCU lock, there is no need to lock/unlock on error path, simply jump out of the loop. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: "Paul E. McKenney" <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>