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* Merge branch 'for-linus' of ↵Linus Torvalds2012-08-012-0/+39
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull second vfs pile from Al Viro: "The stuff in there: fsfreeze deadlock fixes by Jan (essentially, the deadlock reproduced by xfstests 068), symlink and hardlink restriction patches, plus assorted cleanups and fixes. Note that another fsfreeze deadlock (emergency thaw one) is *not* dealt with - the series by Fernando conflicts a lot with Jan's, breaks userland ABI (FIFREEZE semantics gets changed) and trades the deadlock for massive vfsmount leak; this is going to be handled next cycle. There probably will be another pull request, but that stuff won't be in it." Fix up trivial conflicts due to unrelated changes next to each other in drivers/{staging/gdm72xx/usb_boot.c, usb/gadget/storage_common.c} * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (54 commits) delousing target_core_file a bit Documentation: Correct s_umount state for freeze_fs/unfreeze_fs fs: Remove old freezing mechanism ext2: Implement freezing btrfs: Convert to new freezing mechanism nilfs2: Convert to new freezing mechanism ntfs: Convert to new freezing mechanism fuse: Convert to new freezing mechanism gfs2: Convert to new freezing mechanism ocfs2: Convert to new freezing mechanism xfs: Convert to new freezing code ext4: Convert to new freezing mechanism fs: Protect write paths by sb_start_write - sb_end_write fs: Skip atime update on frozen filesystem fs: Add freezing handling to mnt_want_write() / mnt_drop_write() fs: Improve filesystem freezing handling switch the protection of percpu_counter list to spinlock nfsd: Push mnt_want_write() outside of i_mutex btrfs: Push mnt_want_write() outside of i_mutex fat: Push mnt_want_write() outside of i_mutex ...
| * fs: add link restriction audit reportingKees Cook2012-07-291-0/+21
| | | | | | | | | | | | | | | | | | Adds audit messages for unexpected link restriction violations so that system owners will have some sort of potentially actionable information about misbehaving processes. Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * fs: add link restrictionsKees Cook2012-07-291-0/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds symlink and hardlink restrictions to the Linux VFS. Symlinks: A long-standing class of security issues is the symlink-based time-of-check-time-of-use race, most commonly seen in world-writable directories like /tmp. The common method of exploitation of this flaw is to cross privilege boundaries when following a given symlink (i.e. a root process follows a symlink belonging to another user). For a likely incomplete list of hundreds of examples across the years, please see: http://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=/tmp The solution is to permit symlinks to only be followed when outside a sticky world-writable directory, or when the uid of the symlink and follower match, or when the directory owner matches the symlink's owner. Some pointers to the history of earlier discussion that I could find: 1996 Aug, Zygo Blaxell http://marc.info/?l=bugtraq&m=87602167419830&w=2 1996 Oct, Andrew Tridgell http://lkml.indiana.edu/hypermail/linux/kernel/9610.2/0086.html 1997 Dec, Albert D Cahalan http://lkml.org/lkml/1997/12/16/4 2005 Feb, Lorenzo Hernández García-Hierro http://lkml.indiana.edu/hypermail/linux/kernel/0502.0/1896.html 2010 May, Kees Cook https://lkml.org/lkml/2010/5/30/144 Past objections and rebuttals could be summarized as: - Violates POSIX. - POSIX didn't consider this situation and it's not useful to follow a broken specification at the cost of security. - Might break unknown applications that use this feature. - Applications that break because of the change are easy to spot and fix. Applications that are vulnerable to symlink ToCToU by not having the change aren't. Additionally, no applications have yet been found that rely on this behavior. - Applications should just use mkstemp() or O_CREATE|O_EXCL. - True, but applications are not perfect, and new software is written all the time that makes these mistakes; blocking this flaw at the kernel is a single solution to the entire class of vulnerability. - This should live in the core VFS. - This should live in an LSM. (https://lkml.org/lkml/2010/5/31/135) - This should live in an LSM. - This should live in the core VFS. (https://lkml.org/lkml/2010/8/2/188) Hardlinks: On systems that have user-writable directories on the same partition as system files, a long-standing class of security issues is the hardlink-based time-of-check-time-of-use race, most commonly seen in world-writable directories like /tmp. The common method of exploitation of this flaw is to cross privilege boundaries when following a given hardlink (i.e. a root process follows a hardlink created by another user). Additionally, an issue exists where users can "pin" a potentially vulnerable setuid/setgid file so that an administrator will not actually upgrade a system fully. The solution is to permit hardlinks to only be created when the user is already the existing file's owner, or if they already have read/write access to the existing file. Many Linux users are surprised when they learn they can link to files they have no access to, so this change appears to follow the doctrine of "least surprise". Additionally, this change does not violate POSIX, which states "the implementation may require that the calling process has permission to access the existing file"[1]. This change is known to break some implementations of the "at" daemon, though the version used by Fedora and Ubuntu has been fixed[2] for a while. Otherwise, the change has been undisruptive while in use in Ubuntu for the last 1.5 years. [1] http://pubs.opengroup.org/onlinepubs/9699919799/functions/linkat.html [2] http://anonscm.debian.org/gitweb/?p=collab-maint/at.git;a=commitdiff;h=f4114656c3a6c6f6070e315ffdf940a49eda3279 This patch is based on the patches in Openwall and grsecurity, along with suggestions from Al Viro. I have added a sysctl to enable the protected behavior, and documentation. Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | Merge tag 'irqdomain-for-linus' of git://git.secretlab.ca/git/linux-2.6Linus Torvalds2012-07-311-155/+207
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull irqdomain changes from Grant Likely: "Round of refactoring and enhancements to irq_domain infrastructure. This series starts the process of simplifying irqdomain. The ultimate goal is to merge LEGACY, LINEAR and TREE mappings into a single system, but had to back off from that after some last minute bugs. Instead it mainly reorganizes the code and ensures that the reverse map gets populated when the irq is mapped instead of the first time it is looked up. Merging of the irq_domain types is deferred to v3.7 In other news, this series adds helpers for creating static mappings on a linear or tree mapping." * tag 'irqdomain-for-linus' of git://git.secretlab.ca/git/linux-2.6: irqdomain: Improve diagnostics when a domain mapping fails irqdomain: eliminate slow-path revmap lookups irqdomain: Fix irq_create_direct_mapping() to test irq_domain type. irqdomain: Eliminate dedicated radix lookup functions irqdomain: Support for static IRQ mapping and association. irqdomain: Always update revmap when setting up a virq irqdomain: Split disassociating code into separate function irq_domain: correct a minor wrong comment for linear revmap irq_domain: Standardise legacy/linear domain selection irqdomain: Make ops->map hook optional irqdomain: Remove unnecessary test for IRQ_DOMAIN_MAP_LEGACY irqdomain: Simple NUMA awareness. devicetree: add helper inline for retrieving a node's full name
| * | irqdomain: Improve diagnostics when a domain mapping failsMark Brown2012-07-241-6/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | When the map operation fails log the error code we get and add a WARN_ON() so we get a backtrace (which should help work out which interrupt is the source of the issue). Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
| * | irqdomain: eliminate slow-path revmap lookupsGrant Likely2012-07-241-40/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With the current state of irq_domain, the reverse map is always updated when new IRQs get mapped. This means that the irq_find_mapping() function can be simplified to execute the revmap lookup functions unconditionally This patch adds lookup functions for the revmaps that don't yet have one and removes the slow path lookup code path. v8: Broke out unrelated changes into separate patches. Rebased on Paul's irq association patches. v7: Rebased to irqdomain/next for v3.4 and applied before the removal of 'hint' v6: Remove the slow path entirely. The only place where the slow path could get called is for a linear mapping if the hwirq number is larger than the linear revmap size. There shouldn't be any interrupt controllers that do that. v5: rewrite to not use a ->revmap() callback. It is simpler, smaller, safer and faster to open code each of the revmap lookups directly into irq_find_mapping() via a switch statement. v4: Fix build failure on incorrect variable reference. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Milton Miller <miltonm@bga.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Rob Herring <rob.herring@calxeda.com>
| * | Merge remote-tracking branch 'origin' into irqdomain/nextGrant Likely2012-07-2452-2278/+2748
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| * | | irqdomain: Fix irq_create_direct_mapping() to test irq_domain type.Grant Likely2012-07-111-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | irq_create_direct_mapping can only be used with the NOMAP type. Make the function test to ensure it is passed the correct type of irq_domain. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Rob Herring <rob.herring@calxeda.com>
| * | | irqdomain: Eliminate dedicated radix lookup functionsGrant Likely2012-07-111-59/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In preparation to remove the slow revmap path, eliminate the public radix revmap lookup functions. This simplifies the code and makes the slowpath removal patch a lot simpler. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Rob Herring <rob.herring@calxeda.com>
| * | | irqdomain: Support for static IRQ mapping and association.Grant Likely2012-07-111-25/+88
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds a new strict mapping API for supporting creation of linux IRQs at existing positions within the domain. The new routines are as follows: For dynamic allocation and insertion to specified ranges: - irq_create_identity_mapping() - irq_create_strict_mappings() These will allocate and associate a range of linux IRQs at the specified location. This can be used by controllers that have their own static linux IRQ definitions to map a hwirq range to, as well as for platforms that wish to establish 1:1 identity mapping between linux and hwirq space. For insertion to specified ranges by platforms that do their own irq_desc management: - irq_domain_associate() - irq_domain_associate_many() These in turn call back in to the domain's ->map() routine, for further processing by the platform. Disassociation of IRQs get handled through irq_dispose_mapping() as normal. With these in place it should be possible to begin migration of legacy IRQ domains to linear ones, without requiring special handling for static vs dynamic IRQ definitions in DT vs non-DT paths. This also makes it possible for domains with static mappings to adopt whichever tree model best fits their needs, rather than simply restricting them to linear revmaps. Signed-off-by: Paul Mundt <lethal@linux-sh.org> [grant.likely: Reorganized irq_domain_associate{,_many} to have all logic in one place] [grant.likely: Add error checking for unallocated irq_descs at associate time] Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Rob Herring <rob.herring@calxeda.com>
| * | | irqdomain: Always update revmap when setting up a virqGrant Likely2012-07-111-0/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | At irq_setup_virq() time all of the data needed to update the reverse map is available, but the current code ignores it and relies upon the slow path to insert revmap records. This patch adds revmap updating to the setup path so the slow path will no longer be necessary. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Rob Herring <rob.herring@calxeda.com>
| * | | irqdomain: Split disassociating code into separate functionGrant Likely2012-07-111-28/+47
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch moves the irq disassociation code out into a separate function in preparation to extend irq_setup_virq to handle multiple irqs and rename it for use by interrupt controller drivers. The new function will be used by irq_setup_virq() in its error path. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Rob Herring <rob.herring@calxeda.com>
| * | | Merge tag 'v3.5-rc6' into irqdomain/nextGrant Likely2012-07-1114-223/+617
| |\ \ \ | | | | | | | | | | | | | | | Linux 3.5-rc6
| * | | | irq_domain: correct a minor wrong comment for linear revmapDong Aisheng2012-07-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The revmap type should be linear for irq_domain_add_linear function. Signed-off-by: Dong Aisheng <dong.aisheng@linaro.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
| * | | | irq_domain: Standardise legacy/linear domain selectionMark Brown2012-07-111-0/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A large proportion of interrupt controllers that support legacy mappings do so because non-DT systems need to use fixed IRQ numbers when registering devices via buses but can otherwise use a linear mapping. The interrupt controller itself typically is not affected by the mapping used and best practice is to use a linear mapping where possible so drivers frequently select at runtime depending on if a legacy range has been allocated to them. Standardise this behaviour by providing irq_domain_register_simple() which will allocate a linear mapping unless a positive first_irq is provided in which case it will fall back to a legacy mapping. This helps make best practice for irq_domain adoption clearer. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
| * | | | irqdomain: Make ops->map hook optionalGrant Likely2012-06-171-10/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There isn't a really compelling reason to force ->map to be populated, so allow it to be left unset. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Rob Herring <rob.herring@calxeda.com>
| * | | | irqdomain: Remove unnecessary test for IRQ_DOMAIN_MAP_LEGACYGrant Likely2012-06-151-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Where irq_domain_associate() is called in irq_create_mapping, there is no need to test for IRQ_DOMAIN_MAP_LEGACY because it is already tested for earlier in the routine. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Rob Herring <rob.herring@calxeda.com>
| * | | | irqdomain: Simple NUMA awareness.Paul Mundt2012-06-151-5/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While common irqdesc allocation is node aware, the irqdomain code is not. Presently we observe a number of regressions/inconsistencies on NUMA-capable platforms: - Platforms using irqdomains with legacy mappings, where the irq_descs are allocated node-local and the irqdomain data structure is not. - Drivers implementing irqdomains will lose node locality regardless of the underlying struct device's node id. This plugs in NUMA node id proliferation across the various allocation callsites by way of_node_to_nid() node lookup. While of_node_to_nid() does the right thing for OF-capable platforms it doesn't presently handle the non-DT case. This is trivially dealt with by simply wraping in to numa_node_id() unconditionally. Signed-off-by: Paul Mundt <lethal@linux-sh.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Rob Herring <rob.herring@calxeda.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
| * | | | devicetree: add helper inline for retrieving a node's full nameGrant Likely2012-06-151-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The pattern (np ? np->full_name : "<none>") is rather common in the kernel, but can also make for quite long lines. This patch adds a new inline function, of_node_full_name() so that the test for a valid node pointer doesn't need to be open coded at all call sites. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Thomas Gleixner <tglx@linutronix.de>
* | | | | Merge branch 'akpm' (Andrew's patch-bomb)Linus Torvalds2012-07-315-11/+16
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge Andrew's second set of patches: - MM - a few random fixes - a couple of RTC leftovers * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (120 commits) rtc/rtc-88pm80x: remove unneed devm_kfree rtc/rtc-88pm80x: assign ret only when rtc_register_driver fails mm: hugetlbfs: close race during teardown of hugetlbfs shared page tables tmpfs: distribute interleave better across nodes mm: remove redundant initialization mm: warn if pg_data_t isn't initialized with zero mips: zero out pg_data_t when it's allocated memcg: gix memory accounting scalability in shrink_page_list mm/sparse: remove index_init_lock mm/sparse: more checks on mem_section number mm/sparse: optimize sparse_index_alloc memcg: add mem_cgroup_from_css() helper memcg: further prevent OOM with too many dirty pages memcg: prevent OOM with too many dirty pages mm: mmu_notifier: fix freed page still mapped in secondary MMU mm: memcg: only check anon swapin page charges for swap cache mm: memcg: only check swap cache pages for repeated charging mm: memcg: split swapin charge function into private and public part mm: memcg: remove needless !mm fixup to init_mm when charging mm: memcg: remove unneeded shmem charge type ...
| * | | | | mm: allow PF_MEMALLOC from softirq contextMel Gorman2012-07-311-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is needed to allow network softirq packet processing to make use of PF_MEMALLOC. Currently softirq context cannot use PF_MEMALLOC due to it not being associated with a task, and therefore not having task flags to fiddle with - thus the gfp to alloc flag mapping ignores the task flags when in interrupts (hard or soft) context. Allowing softirqs to make use of PF_MEMALLOC therefore requires some trickery. This patch borrows the task flags from whatever process happens to be preempted by the softirq. It then modifies the gfp to alloc flags mapping to not exclude task flags in softirq context, and modify the softirq code to save, clear and restore the PF_MEMALLOC flag. The save and clear, ensures the preempted task's PF_MEMALLOC flag doesn't leak into the softirq. The restore ensures a softirq's PF_MEMALLOC flag cannot leak back into the preempted process. This should be safe due to the following reasons Softirqs can run on multiple CPUs sure but the same task should not be executing the same softirq code. Neither should the softirq handler be preempted by any other softirq handler so the flags should not leak to an unrelated softirq. Softirqs re-enable hardware interrupts in __do_softirq() so can be preempted by hardware interrupts so PF_MEMALLOC is inherited by the hard IRQ. However, this is similar to a process in reclaim being preempted by a hardirq. While PF_MEMALLOC is set, gfp_to_alloc_flags() distinguishes between hard and soft irqs and avoids giving a hardirq the ALLOC_NO_WATERMARKS flag. If the softirq is deferred to ksoftirq then its flags may be used instead of a normal tasks but as the softirq cannot be preempted, the PF_MEMALLOC flag does not leak to other code by accident. [davem@davemloft.net: Document why PF_MEMALLOC is safe] Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Mel Gorman <mgorman@suse.de> Cc: David Miller <davem@davemloft.net> Cc: Neil Brown <neilb@suse.de> Cc: Mike Christie <michaelc@cs.wisc.edu> Cc: Eric B Munson <emunson@mgebm.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Sebastian Andrzej Siewior <sebastian@breakpoint.cc> Cc: Mel Gorman <mgorman@suse.de> Cc: Christoph Lameter <cl@linux.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | | mm/hotplug: correctly setup fallback zonelists when creating new pgdatJiang Liu2012-07-311-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When hotadd_new_pgdat() is called to create new pgdat for a new node, a fallback zonelist should be created for the new node. There's code to try to achieve that in hotadd_new_pgdat() as below: /* * The node we allocated has no zone fallback lists. For avoiding * to access not-initialized zonelist, build here. */ mutex_lock(&zonelists_mutex); build_all_zonelists(pgdat, NULL); mutex_unlock(&zonelists_mutex); But it doesn't work as expected. When hotadd_new_pgdat() is called, the new node is still in offline state because node_set_online(nid) hasn't been called yet. And build_all_zonelists() only builds zonelists for online nodes as: for_each_online_node(nid) { pg_data_t *pgdat = NODE_DATA(nid); build_zonelists(pgdat); build_zonelist_cache(pgdat); } Though we hope to create zonelist for the new pgdat, but it doesn't. So add a new parameter "pgdat" the build_all_zonelists() to build pgdat for the new pgdat too. Signed-off-by: Jiang Liu <liuj97@gmail.com> Signed-off-by: Xishi Qiu <qiuxishi@huawei.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.cz> Cc: Minchan Kim <minchan@kernel.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Tony Luck <tony.luck@intel.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Keping Chen <chenkeping@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | | memcg: rename config variablesAndrew Morton2012-07-311-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sanity: CONFIG_CGROUP_MEM_RES_CTLR -> CONFIG_MEMCG CONFIG_CGROUP_MEM_RES_CTLR_SWAP -> CONFIG_MEMCG_SWAP CONFIG_CGROUP_MEM_RES_CTLR_SWAP_ENABLED -> CONFIG_MEMCG_SWAP_ENABLED CONFIG_CGROUP_MEM_RES_CTLR_KMEM -> CONFIG_MEMCG_KMEM [mhocko@suse.cz: fix missed bits] Cc: Glauber Costa <glommer@parallels.com> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Hugh Dickins <hughd@google.com> Cc: Tejun Heo <tj@kernel.org> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: 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>
| * | | | | mm: prepare for removal of obsolete /proc/sys/vm/nr_pdflush_threadsWanpeng Li2012-07-312-6/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since per-BDI flusher threads were introduced in 2.6, the pdflush mechanism is not used any more. But the old interface exported through /proc/sys/vm/nr_pdflush_threads still exists and is obviously useless. For back-compatibility, printk warning information and return 2 to notify the users that the interface is removed. Signed-off-by: Wanpeng Li <liwp@linux.vnet.ibm.com> Cc: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | | mm: account the total_vm in the vm_stat_account()Huang Shijie2012-07-311-3/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | vm_stat_account() accounts the shared_vm, stack_vm and reserved_vm now. But we can also account for total_vm in the vm_stat_account() which makes the code tidy. Even for mprotect_fixup(), we can get the right result in the end. Signed-off-by: Huang Shijie <shijie8@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | | Merge tag 'random_for_linus' of ↵Linus Torvalds2012-07-312-21/+3
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random Pull random subsystem patches from Ted Ts'o: "This patch series contains a major revamp of how we collect entropy from interrupts for /dev/random and /dev/urandom. The goal is to addresses weaknesses discussed in the paper "Mining your Ps and Qs: Detection of Widespread Weak Keys in Network Devices", by Nadia Heninger, Zakir Durumeric, Eric Wustrow, J. Alex Halderman, which will be published in the Proceedings of the 21st Usenix Security Symposium, August 2012. (See https://factorable.net for more information and an extended version of the paper.)" Fix up trivial conflicts due to nearby changes in drivers/{mfd/ab3100-core.c, usb/gadget/omap_udc.c} * tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random: (33 commits) random: mix in architectural randomness in extract_buf() dmi: Feed DMI table to /dev/random driver random: Add comment to random_initialize() random: final removal of IRQF_SAMPLE_RANDOM um: remove IRQF_SAMPLE_RANDOM which is now a no-op sparc/ldc: remove IRQF_SAMPLE_RANDOM which is now a no-op [ARM] pxa: remove IRQF_SAMPLE_RANDOM which is now a no-op board-palmz71: remove IRQF_SAMPLE_RANDOM which is now a no-op isp1301_omap: remove IRQF_SAMPLE_RANDOM which is now a no-op pxa25x_udc: remove IRQF_SAMPLE_RANDOM which is now a no-op omap_udc: remove IRQF_SAMPLE_RANDOM which is now a no-op goku_udc: remove IRQF_SAMPLE_RANDOM which was commented out uartlite: remove IRQF_SAMPLE_RANDOM which is now a no-op drivers: hv: remove IRQF_SAMPLE_RANDOM which is now a no-op xen-blkfront: remove IRQF_SAMPLE_RANDOM which is now a no-op n2_crypto: remove IRQF_SAMPLE_RANDOM which is now a no-op pda_power: remove IRQF_SAMPLE_RANDOM which is now a no-op i2c-pmcmsp: remove IRQF_SAMPLE_RANDOM which is now a no-op input/serio/hp_sdc.c: remove IRQF_SAMPLE_RANDOM which is now a no-op mfd: remove IRQF_SAMPLE_RANDOM which is now a no-op ...
| * | | | | | random: remove rand_initialize_irq()Theodore Ts'o2012-07-191-17/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With the new interrupt sampling system, we are no longer using the timer_rand_state structure in the irq descriptor, so we can stop initializing it now. [ Merged in fixes from Sedat to find some last missing references to rand_initialize_irq() ] Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Sedat Dilek <sedat.dilek@gmail.com>
| * | | | | | random: make 'add_interrupt_randomness()' do something saneTheodore Ts'o2012-07-141-4/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We've been moving away from add_interrupt_randomness() for various reasons: it's too expensive to do on every interrupt, and flooding the CPU with interrupts could theoretically cause bogus floods of entropy from a somewhat externally controllable source. This solves both problems by limiting the actual randomness addition to just once a second or after 64 interrupts, whicever comes first. During that time, the interrupt cycle data is buffered up in a per-cpu pool. Also, we make sure the the nonblocking pool used by urandom is initialized before we start feeding the normal input pool. This assures that /dev/urandom is returning unpredictable data as soon as possible. (Based on an original patch by Linus, but significantly modified by tytso.) Tested-by: Eric Wustrow <ewust@umich.edu> Reported-by: Eric Wustrow <ewust@umich.edu> Reported-by: Nadia Heninger <nadiah@cs.ucsd.edu> Reported-by: Zakir Durumeric <zakir@umich.edu> Reported-by: J. Alex Halderman <jhalderm@umich.edu>. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: stable@vger.kernel.org
* | | | | | | Merge branch 'perf-core-for-linus' of ↵Linus Torvalds2012-07-312-117/+98
|\ \ \ \ \ \ \ | |_|/ / / / / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf updates from Ingo Molnar: "The biggest changes are Intel Nehalem-EX PMU uncore support, uprobes updates/cleanups/fixes from Oleg and diverse tooling updates (mostly fixes) now that Arnaldo is back from vacation." * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits) uprobes: __replace_page() needs munlock_vma_page() uprobes: Rename vma_address() and make it return "unsigned long" uprobes: Fix register_for_each_vma()->vma_address() check uprobes: Introduce vaddr_to_offset(vma, vaddr) uprobes: Teach build_probe_list() to consider the range uprobes: Remove insert_vm_struct()->uprobe_mmap() uprobes: Remove copy_vma()->uprobe_mmap() uprobes: Fix overflow in vma_address()/find_active_uprobe() uprobes: Suppress uprobe_munmap() from mmput() uprobes: Uprobe_mmap/munmap needs list_for_each_entry_safe() uprobes: Clean up and document write_opcode()->lock_page(old_page) uprobes: Kill write_opcode()->lock_page(new_page) uprobes: __replace_page() should not use page_address_in_vma() uprobes: Don't recheck vma/f_mapping in write_opcode() perf/x86: Fix missing struct before structure name perf/x86: Fix format definition of SNB-EP uncore QPI box perf/x86: Make bitfield unsigned perf/x86: Fix LLC-* and node-* events on Intel SandyBridge perf/x86: Add Intel Nehalem-EX uncore support perf/x86: Fix typo in format definition of uncore PCU filter ...
| * | | | | | uprobes: __replace_page() needs munlock_vma_page()Oleg Nesterov2012-07-301-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Like do_wp_page(), __replace_page() should do munlock_vma_page() for the case when the old page still has other !VM_LOCKED mappings. Unfortunately this needs mm/internal.h. Also, move put_page() outside of ptl lock. This doesn't really matter but looks a bit better. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com> Cc: Anton Arapov <anton@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/20120729182249.GA20372@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | uprobes: Rename vma_address() and make it return "unsigned long"Oleg Nesterov2012-07-301-10/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1. vma_address() returns loff_t, this looks confusing and this is unnecessary after the previous change. Make it return "ulong", all callers truncate the result anyway. 2. Its name conflicts with mm/rmap.c:vma_address(), rename it to offset_to_vaddr(), this matches vaddr_to_offset(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com> Cc: Anton Arapov <anton@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/20120729182247.GA20365@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | uprobes: Fix register_for_each_vma()->vma_address() checkOleg Nesterov2012-07-301-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1. register_for_each_vma() checks that vma_address() == vaddr, but this is not enough. We should also ensure that vaddr >= vm_start, find_vma() guarantees "vaddr < vm_end" only. 2. After the prevous changes, register_for_each_vma() is the only reason why vma_address() has to return loff_t, all other users know that we have the valid mapping at this offset and thus the overflow is not possible. Change the code to use vaddr_to_offset() instead, imho this looks more clean/understandable and now we can change vma_address(). 3. While at it, remove the unnecessary type-cast. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com> Cc: Anton Arapov <anton@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/20120729182244.GA20362@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | uprobes: Introduce vaddr_to_offset(vma, vaddr)Oleg Nesterov2012-07-301-6/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add the new helper, vaddr_to_offset(vma, vaddr) which returns the offset in vma->vm_file this vaddr is mapped at. Change build_probe_list() and find_active_uprobe() to use the new helper, the next patch adds another user. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com> Cc: Anton Arapov <anton@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/20120729182242.GA20355@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | uprobes: Teach build_probe_list() to consider the rangeOleg Nesterov2012-07-301-53/+50
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently build_probe_list() builds the list of all uprobes attached to the given inode, and the caller should filter out those who don't fall into the [start,end) range, this is sub-optimal. This patch turns find_least_offset_node() into find_node_in_range() which returns the first node inside the [min,max] range, and changes build_probe_list() to use this node as a starting point for rb_prev() and rb_next() to find all other nodes the caller needs. The resulting list is no longer sorted but we do not care. This can speed up both build_probe_list() and the callers, but there is another reason to introduce find_node_in_range(). It can be used to figure out whether the given vma has uprobes or not, this will be needed soon. While at it, shift INIT_LIST_HEAD(tmp_list) into build_probe_list(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com> Cc: Anton Arapov <anton@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/20120729182240.GA20352@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | uprobes: Fix overflow in vma_address()/find_active_uprobe()Oleg Nesterov2012-07-301-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | vma->vm_pgoff is "unsigned long", it should be promoted to loff_t before the multiplication to avoid the overflow. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com> Cc: Anton Arapov <anton@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/20120729182233.GA20339@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | uprobes: Suppress uprobe_munmap() from mmput()Oleg Nesterov2012-07-301-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | uprobe_munmap() does get_user_pages() and it is also called from the final mmput()->exit_mmap() path. This slows down exit/mmput() for no reason, and I think it is simply dangerous/wrong to try to fault-in a page into the dying mm. If nothing else, this happens after the last sync_mm_rss(), afaics handle_mm_fault() can change the task->rss_stat and make the subsequent check_mm() unhappy. Change uprobe_munmap() to check mm->mm_users != 0. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com> Cc: Anton Arapov <anton@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/20120729182231.GA20336@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | uprobes: Uprobe_mmap/munmap needs list_for_each_entry_safe()Oleg Nesterov2012-07-301-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The bug was introduced by me in 449d0d7c ("uprobes: Simplify the usage of uprobe->pending_list"). Yes, we do not care about uprobe->pending_list after return and nobody can remove the current list entry, but put_uprobe(uprobe) can actually free it and thus we need list_for_each_safe(). Reported-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com> Cc: Anton Arapov <anton@redhat.com> Link: http://lkml.kernel.org/r/20120729182229.GA20329@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | uprobes: Clean up and document write_opcode()->lock_page(old_page)Oleg Nesterov2012-07-301-13/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The comment above write_opcode()->lock_page(old_page) tells about the race with do_wp_page(). I don't really understand which exactly race it means, but afaics this lock_page() was not enough to close all races with do_wp_page(). Anyway, since: 77fc4af1b59d uprobes: Change register_for_each_vma() to take mm->mmap_sem for writing this code is always called with ->mmap_sem held for writing, so we can forget about do_wp_page(). However, we can't simply remove this lock_page(), and the only (afaics) reason is __replace_page()->try_to_free_swap(). Nothing in write_opcode() needs it, move it into __replace_page() and fix the comment. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com> Cc: Anton Arapov <anton@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/20120729182220.GA20322@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | uprobes: Kill write_opcode()->lock_page(new_page)Oleg Nesterov2012-07-301-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | write_opcode() does lock_page(new_page) for no reason. Nobody can see this page until __replace_page() exposes it under ptl lock, and we do nothing with this page after pte_unmap_unlock(). If nothing else, the similar code in do_wp_page() doesn't lock the new page for page_add_new_anon_rmap/set_pte_at_notify. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com> Cc: Anton Arapov <anton@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/20120729182218.GA20315@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | uprobes: __replace_page() should not use page_address_in_vma()Oleg Nesterov2012-07-301-7/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | page_address_in_vma(old_page) in __replace_page() is ugly and wrong. The caller already knows the correct virtual address, this page was found by get_user_pages(vaddr). However, page_address_in_vma() can actually fail if page->mapping was cleared by __delete_from_page_cache() after get_user_pages() returns. But this means the race with page reclaim, write_opcode() should not fail, it should retry and read this page again. Probably the race with remove_mapping() is not possible due to page_freeze_refs() logic, but afaics at least shmem_writepage()->shmem_delete_from_page_cache() can clear ->mapping. We could change __replace_page() to return -EAGAIN in this case, but it would be better to simply use the caller's vaddr and rely on page_check_address(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com> Cc: Anton Arapov <anton@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/20120729182216.GA20311@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | uprobes: Don't recheck vma/f_mapping in write_opcode()Oleg Nesterov2012-07-301-18/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | write_opcode() rechecks valid_vma() and ->f_mapping, this is pointless. The caller, register_for_each_vma() or uprobe_mmap(), has already done these checks under mmap_sem. To clarify, uprobe_mmap() checks valid_vma() only, but we can rely on build_probe_list(vm_file->f_mapping->host). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar.vnet.ibm.com> Cc: Anton Arapov <anton@redhat.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Link: http://lkml.kernel.org/r/20120729182212.GA20304@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | sched: Deliver sched_switch events to the current taskAndrew Vagin2012-07-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Otherwise they can't be filtered for a defined task: perf record -e sched:sched_switch ./foo This command doesn't report any events without this patch. I think it isn't a security concern if someone knows who will be executed next - this can already be observed by polling /proc state. By default perf is disabled for non-root users in any case. I need these events for profiling sleep times. sched_switch is used for getting callchains and sched_stat_* is used for getting time periods. These events are combined in user space, then it can be analyzed by perf tools. Signed-off-by: Andrew Vagin <avagin@openvz.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Arun Sharma <asharma@fb.com> Link: http://lkml.kernel.org/r/1342088069-1005148-1-git-send-email-avagin@openvz.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | | | | | resource: make sure requested range is included in the root rangeOctavian Purdila2012-07-301-1/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the requested range is outside of the root range the logic in __reserve_region_with_split will cause an infinite recursion which will overflow the stack as seen in the warning bellow. This particular stack overflow was caused by requesting the (100000000-107ffffff) range while the root range was (0-ffffffff). In this case __request_resource would return the whole root range as conflict range (i.e. 0-ffffffff). Then, the logic in __reserve_region_with_split would continue the recursion requesting the new range as (conflict->end+1, end) which incidentally in this case equals the originally requested range. This patch aborts looking for an usable range when the request does not intersect with the root range. When the request partially overlaps with the root range, it ajust the request to fall in the root range and then continues with the new request. When the request is modified or aborted errors and a stack trace are logged to allow catching the errors in the upper layers. [ 5.968374] WARNING: at kernel/sched.c:4129 sub_preempt_count+0x63/0x89() [ 5.975150] Modules linked in: [ 5.978184] Pid: 1, comm: swapper Not tainted 3.0.22-mid27-00004-gb72c817 #46 [ 5.985324] Call Trace: [ 5.987759] [<c1039dfc>] ? console_unlock+0x17b/0x18d [ 5.992891] [<c1039620>] warn_slowpath_common+0x48/0x5d [ 5.998194] [<c1031758>] ? sub_preempt_count+0x63/0x89 [ 6.003412] [<c1039644>] warn_slowpath_null+0xf/0x13 [ 6.008453] [<c1031758>] sub_preempt_count+0x63/0x89 [ 6.013499] [<c14d60c4>] _raw_spin_unlock+0x27/0x3f [ 6.018453] [<c10c6349>] add_partial+0x36/0x3b [ 6.022973] [<c10c7c0a>] deactivate_slab+0x96/0xb4 [ 6.027842] [<c14cf9d9>] __slab_alloc.isra.54.constprop.63+0x204/0x241 [ 6.034456] [<c103f78f>] ? kzalloc.constprop.5+0x29/0x38 [ 6.039842] [<c103f78f>] ? kzalloc.constprop.5+0x29/0x38 [ 6.045232] [<c10c7dc9>] kmem_cache_alloc_trace+0x51/0xb0 [ 6.050710] [<c103f78f>] ? kzalloc.constprop.5+0x29/0x38 [ 6.056100] [<c103f78f>] kzalloc.constprop.5+0x29/0x38 [ 6.061320] [<c17b45e9>] __reserve_region_with_split+0x1c/0xd1 [ 6.067230] [<c17b4693>] __reserve_region_with_split+0xc6/0xd1 ... [ 7.179057] [<c17b4693>] __reserve_region_with_split+0xc6/0xd1 [ 7.184970] [<c17b4779>] reserve_region_with_split+0x30/0x42 [ 7.190709] [<c17a8ebf>] e820_reserve_resources_late+0xd1/0xe9 [ 7.196623] [<c17c9526>] pcibios_resource_survey+0x23/0x2a [ 7.202184] [<c17cad8a>] pcibios_init+0x23/0x35 [ 7.206789] [<c17ca574>] pci_subsys_init+0x3f/0x44 [ 7.211659] [<c1002088>] do_one_initcall+0x72/0x122 [ 7.216615] [<c17ca535>] ? pci_legacy_init+0x3d/0x3d [ 7.221659] [<c17a27ff>] kernel_init+0xa6/0x118 [ 7.226265] [<c17a2759>] ? start_kernel+0x334/0x334 [ 7.231223] [<c14d7482>] kernel_thread_helper+0x6/0x10 Signed-off-by: Octavian Purdila <octavian.purdila@intel.com> Signed-off-by: Ram Pai <linuxram@us.ibm.com> Cc: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | | | taskstats: check nla_reserve() returnAlan Cox2012-07-301-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Addresses https://bugzilla.kernel.org/show_bug.cgi?id=44621 Reported-by: <rucsoftsec@gmail.com> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | | | sysctl: suppress kmemleak messagesSteven Rostedt2012-07-301-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | register_sysctl_table() is a strange function, as it makes internal allocations (a header) to register a sysctl_table. This header is a handle to the table that is created, and can be used to unregister the table. But if the table is permanent and never unregistered, the header acts the same as a static variable. Unfortunately, this allocation of memory that is never expected to be freed fools kmemleak in thinking that we have leaked memory. For those sysctl tables that are never unregistered, and have no pointer referencing them, kmemleak will think that these are memory leaks: unreferenced object 0xffff880079fb9d40 (size 192): comm "swapper/0", pid 0, jiffies 4294667316 (age 12614.152s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffff8146b590>] kmemleak_alloc+0x73/0x98 [<ffffffff8110a935>] kmemleak_alloc_recursive.constprop.42+0x16/0x18 [<ffffffff8110b852>] __kmalloc+0x107/0x153 [<ffffffff8116fa72>] kzalloc.constprop.8+0xe/0x10 [<ffffffff811703c9>] __register_sysctl_paths+0xe1/0x160 [<ffffffff81170463>] register_sysctl_paths+0x1b/0x1d [<ffffffff8117047d>] register_sysctl_table+0x18/0x1a [<ffffffff81afb0a1>] sysctl_init+0x10/0x14 [<ffffffff81b05a6f>] proc_sys_init+0x2f/0x31 [<ffffffff81b0584c>] proc_root_init+0xa5/0xa7 [<ffffffff81ae5b7e>] start_kernel+0x3d0/0x40a [<ffffffff81ae52a7>] x86_64_start_reservations+0xae/0xb2 [<ffffffff81ae53ad>] x86_64_start_kernel+0x102/0x111 [<ffffffffffffffff>] 0xffffffffffffffff The sysctl_base_table used by sysctl itself is one such instance that registers the table to never be unregistered. Use kmemleak_not_leak() to suppress the kmemleak false positive. Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | | | kdump: append newline to the last lien of vmcoreinfo noteVivek Goyal2012-07-301-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The last line of vmcoreinfo note does not end with \n. Parsing all the lines in note becomes easier if all lines end with \n instead of trying to special case the last line. I know at least one tool, vmcore-dmesg in kexec-tools tree which made the assumption that all lines end with \n. I think it is a good idea to fix it. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Atsushi Kumagai <kumagai-atsushi@mxc.nes.nec.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | | | fork: fix error handling in dup_task()Akinobu Mita2012-07-301-12/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The function dup_task() may fail at the following function calls in the following order. 0) alloc_task_struct_node() 1) alloc_thread_info_node() 2) arch_dup_task_struct() Error by 0) is not a matter, it can just return. But error by 1) requires releasing task_struct allocated by 0) before it returns. Likewise, error by 2) requires releasing task_struct and thread_info allocated by 0) and 1). The existing error handling calls free_task_struct() and free_thread_info() which do not only release task_struct and thread_info, but also call architecture specific arch_release_task_struct() and arch_release_thread_info(). The problem is that task_struct and thread_info are not fully initialized yet at this point, but arch_release_task_struct() and arch_release_thread_info() are called with them. For example, x86 defines its own arch_release_task_struct() that releases a task_xstate. If alloc_thread_info_node() fails in dup_task(), arch_release_task_struct() is called with task_struct which is just allocated and filled with garbage in this error handling. This actually happened with tools/testing/fault-injection/failcmd.sh # env FAILCMD_TYPE=fail_page_alloc \ ./tools/testing/fault-injection/failcmd.sh --times=100 \ --min-order=0 --ignore-gfp-wait=0 \ -- make -C tools/testing/selftests/ run_tests In order to fix this issue, make free_{task_struct,thread_info}() not to call arch_release_{task_struct,thread_info}() and call arch_release_{task_struct,thread_info}() implicitly where needed. Default arch_release_task_struct() and arch_release_thread_info() are defined as empty by default. So this change only affects the architectures which implement their own arch_release_task_struct() or arch_release_thread_info() as listed below. arch_release_task_struct(): x86, sh arch_release_thread_info(): mn10300, tile Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: David Howells <dhowells@redhat.com> Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Chris Metcalf <cmetcalf@tilera.com> Cc: Salman Qazi <sqazi@google.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | | | revert "sched: Fix fork() error path to not crash"Andrew Morton2012-07-301-8/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To make way for "fork: fix error handling in dup_task()", which fixes the errors more completely. Cc: Salman Qazi <sqazi@google.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Cc: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | | | fork: use vma_pages() to simplify the codeHuang Shijie2012-07-301-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current code can be replaced by vma_pages(). So use it to simplify the code. [akpm@linux-foundation.org: initialise `len' at its definition site] Signed-off-by: Huang Shijie <shijie8@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | | | kmod: avoid deadlock from recursive kmod callTetsuo Handa2012-07-301-2/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The system deadlocks (at least since 2.6.10) when call_usermodehelper(UMH_WAIT_EXEC) request triggers call_usermodehelper(UMH_WAIT_PROC) request. This is because "khelper thread is waiting for the worker thread at wait_for_completion() in do_fork() since the worker thread was created with CLONE_VFORK flag" and "the worker thread cannot call complete() because do_execve() is blocked at UMH_WAIT_PROC request" and "the khelper thread cannot start processing UMH_WAIT_PROC request because the khelper thread is waiting for the worker thread at wait_for_completion() in do_fork()". The easiest example to observe this deadlock is to use a corrupted /sbin/hotplug binary (like shown below). # : > /tmp/dummy # chmod 755 /tmp/dummy # echo /tmp/dummy > /proc/sys/kernel/hotplug # modprobe whatever call_usermodehelper("/tmp/dummy", UMH_WAIT_EXEC) is called from kobject_uevent_env() in lib/kobject_uevent.c upon loading/unloading a module. do_execve("/tmp/dummy") triggers a call to request_module("binfmt-0000") from search_binary_handler() which in turn calls call_usermodehelper(UMH_WAIT_PROC). In order to avoid deadlock, as a for-now and easy-to-backport solution, do not try to call wait_for_completion() in call_usermodehelper_exec() if the worker thread was created by khelper thread with CLONE_VFORK flag. Future and fundamental solution might be replacing singleton khelper thread with some workqueue so that recursive calls up to max_active dependency loop can be handled without deadlock. [akpm@linux-foundation.org: add comment to kmod_thread_locker] Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Arjan van de Ven <arjan@linux.intel.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Tejun Heo <tj@kernel.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>