linux/mm
Shiraz Hashim 4859611992 mm: pagewalk: call pte_hole() for VM_PFNMAP during walk_page_range
commit 23aaed6659 upstream.

walk_page_range() silently skips vma having VM_PFNMAP set, which leads
to undesirable behaviour at client end (who called walk_page_range).
Userspace applications get the wrong data, so the effect is like just
confusing users (if the applications just display the data) or sometimes
killing the processes (if the applications do something with
misunderstanding virtual addresses due to the wrong data.)

For example for pagemap_read, when no callbacks are called against
VM_PFNMAP vma, pagemap_read may prepare pagemap data for next virtual
address range at wrong index.

Eventually userspace may get wrong pagemap data for a task.
Corresponding to a VM_PFNMAP marked vma region, kernel may report
mappings from subsequent vma regions.  User space in turn may account
more pages (than really are) to the task.

In my case I was using procmem, procrack (Android utility) which uses
pagemap interface to account RSS pages of a task.  Due to this bug it
was giving a wrong picture for vmas (with VM_PFNMAP set).

Fixes: a9ff785e44 ("mm/pagewalk.c: walk_page_range should avoid VM_PFNMAP areas")
Signed-off-by: Shiraz Hashim <shashim@codeaurora.org>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
History 2015-02-10 13:38:47 +00:00
..
backing-dev.c arch: Mass conversion of smp_mb__*() 2014-04-18 14:20:48 +02:00
balloon_compaction.c mm: print more details for bad_page() 2014-01-23 16:36:50 -08:00
bootmem.c mem-hotplug: reset node managed pages when hot-adding a new pgdat 2014-11-27 11:21:50 +00:00
cleancache.c mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE 2014-01-23 16:36:50 -08:00
compaction.c mm, compaction: properly signal and act upon lock and need_sched() contention 2014-06-04 16:54:11 -07:00
debug-pagealloc.c mm, x86: Remove debug_pagealloc_enabled 2011-12-06 09:24:07 +01:00
dmapool.c Fix unbalanced mutex in dma_pool_create(). 2014-10-05 13:41:09 -07:00
early_ioremap.c mm: create generic early_ioremap() support 2014-04-07 16:36:15 -07:00
fadvise.c teach SYSCALL_DEFINE<n> how to deal with long long/unsigned long long 2013-03-03 22:46:22 -05:00
failslab.c switch debugfs to umode_t 2012-01-03 22:54:56 -05:00
filemap.c mm: get rid of radix tree gfp mask for pagecache_get_page 2015-02-04 10:57:56 +00:00
filemap_xip.c seqcount: Add lockdep functionality to seqcount/seqlock structures 2013-11-06 12:40:26 +01:00
fremap.c mm: mark remap_file_pages() syscall as deprecated 2014-06-06 16:08:17 -07:00
frontswap.c mm: frontswap: invalidate expired data on a dup-store failure 2014-12-10 17:49:41 +00:00
gup.c vm: add VM_FAULT_SIGSEGV handling support 2015-02-04 10:58:27 +00:00
highmem.c Some nice cleanups, and even a patch my wife did as a "live" demo for 2012-12-20 08:37:05 -08:00
huge_memory.c mm, thp: fix collapsing of hugepages on madvise 2014-11-13 11:48:56 +00:00
hugetlb.c mm: fix potential infinite loop in dissolve_free_huge_pages() 2014-09-17 09:21:54 -07:00
hugetlb_cgroup.c cgroup: remove css_parent() 2014-05-16 13:22:48 -04:00
hwpoison-inject.c mm/hwpoison: add '#' to hwpoison_inject 2014-01-21 16:19:48 -08:00
init-mm.c atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
internal.h mm, compaction: properly signal and act upon lock and need_sched() contention 2014-06-04 16:54:11 -07:00
interval_tree.c mm: add CONFIG_DEBUG_VM_RB build option 2012-10-09 16:22:42 +09:00
iov_iter.c Fix thinko in iov_iter_single_seg_count 2014-11-27 11:21:48 +00:00
Kconfig mm/zsmalloc: make zsmalloc module-buildable 2014-06-04 16:54:14 -07:00
Kconfig.debug mm: more intensive memory corruption debugging 2012-01-10 16:30:42 -08:00
kmemcheck.c kmemcheck: Fix build errors due to missing slab.h 2010-03-30 22:02:32 +09:00
kmemleak-test.c mm/kmemleak-test.c: use pr_fmt for logging 2014-06-06 16:08:18 -07:00
kmemleak.c mm: introduce kmemleak_update_trace() 2014-06-06 16:08:17 -07:00
ksm.c vm: add VM_FAULT_SIGSEGV handling support 2015-02-04 10:58:27 +00:00
list_lru.c mm: keep page cache radix tree nodes in check 2014-04-03 16:21:01 -07:00
maccess.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
madvise.c mm: madvise: fix MADV_WILLNEED on shmem swapouts 2014-05-23 09:37:29 -07:00
Makefile mm: move get_user_pages()-related code to separate file 2014-06-04 16:54:04 -07:00
memblock.c memblock, memhotplug: fix wrong type in memblock_find_in_range_node(). 2014-10-05 13:41:03 -07:00
memcontrol.c memcg: remove extra newlines from memcg oom kill log 2015-02-04 10:58:34 +00:00
memory-failure.c hwpoison: call action_result() in failure path of hwpoison_user_mappings() 2014-07-30 17:16:13 -07:00
memory.c vm: make stack guard page errors return VM_FAULT_SIGSEGV rather than SIGBUS 2015-02-04 10:58:27 +00:00
memory_hotplug.c mem-hotplug: reset node present pages when hot-adding a new pgdat 2014-11-27 11:21:51 +00:00
mempolicy.c Merge branch 'for-3.16-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup 2014-07-10 11:38:23 -07:00
mempool.c mm/mempool.c: update the kmemleak stack trace for mempool allocations 2014-06-06 16:08:17 -07:00
migrate.c mm: migrate: Close race between migration completion and mprotect 2014-10-09 12:23:48 -07:00
mincore.c mm + fs: prepare for non-page entries in page cache radix trees 2014-04-03 16:21:00 -07:00
mlock.c mm: try_to_unmap_cluster() should lock_page() before mlocking 2014-04-07 16:35:57 -07:00
mm_init.c mm: bring back /sys/kernel/mm 2014-01-27 21:02:39 -08:00
mmap.c mm: fix corner case in anon_vma endless growing prevention 2015-01-16 14:34:36 +00:00
mmu_context.c sched/mm: call finish_arch_post_lock_switch in idle_task_exit and use_mm 2014-02-21 08:50:17 +01:00
mmu_notifier.c mm: audit/fix non-modular users of module_init in core code 2014-01-23 16:36:52 -08:00
mmzone.c mm: numa: Change page last {nid,pid} into {cpu,pid} 2013-10-09 14:47:45 +02:00
mprotect.c mm: move mmu notifier call from change_protection to change_pmd_range 2014-04-07 16:35:50 -07:00
mremap.c mm, thp: close race between mremap() and split_huge_page() 2014-05-11 17:55:48 +09:00
msync.c msync: fix incorrect fstart calculation 2014-07-03 09:21:53 -07:00
nobootmem.c mem-hotplug: reset node managed pages when hot-adding a new pgdat 2014-11-27 11:21:50 +00:00
nommu.c mm: nommu: per-thread vma cache fix 2014-06-23 16:47:43 -07:00
oom_kill.c OOM, PM: OOM killed task shouldn't escape PM suspend 2014-11-05 11:43:09 +00:00
page-writeback.c mm: protect set_page_dirty() from ongoing truncation 2015-01-16 14:34:32 +00:00
page_alloc.c OOM, PM: OOM killed task shouldn't escape PM suspend 2014-11-05 11:43:09 +00:00
page_cgroup.c cgroup/kmemleak: add kmemleak_free() for cgroup deallocations. 2014-11-13 11:48:55 +00:00
page_io.c fix __swap_writepage() compile failure on old gcc versions 2014-06-14 19:30:48 -05:00
page_isolation.c mm: memory-hotplug: enable memory hotplug to handle hugepage 2013-09-11 15:57:48 -07:00
pagewalk.c mm: pagewalk: call pte_hole() for VM_PFNMAP during walk_page_range 2015-02-10 13:38:47 +00:00
percpu-km.c percpu: clear memory allocated with the km allocator 2010-10-02 10:28:42 +03:00
percpu-vm.c percpu: perform tlb flush after pcpu_map_pages() failure 2014-10-05 13:41:06 -07:00
percpu.c Revert "percpu: free percpu allocation info for uniprocessor system" 2014-11-14 15:20:06 +00:00
pgtable-generic.c mm: fix TLB flush race between migration, and change_protection_range 2013-12-18 19:04:51 -08:00
process_vm_access.c start adding the tag to iov_iter 2014-05-06 17:32:49 -04:00
quicklist.c mm: delete various needless include <linux/module.h> 2011-10-31 09:20:11 -04:00
readahead.c mm/readahead.c: inline ra_submit 2014-04-07 16:35:58 -07:00
rmap.c mm: prevent endless growth of anon_vma hierarchy 2015-01-16 14:34:31 +00:00
shmem.c shmem: fix nlink for rename overwrite directory 2014-10-05 13:41:03 -07:00
slab.c slab: fix nodeid bounds check for non-contiguous node IDs 2014-12-10 17:49:44 +00:00
slab.h memcg, slab: merge memcg_{bind,release}_pages to memcg_{un}charge_slab 2014-06-04 16:54:01 -07:00
slab_common.c Merge branch 'slab/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux into for-3.16-rcX 2014-07-22 18:38:27 -04:00
slob.c slab: get_online_mems for kmem_cache_{create,destroy,shrink} 2014-06-04 16:53:59 -07:00
slub.c slub: fix off by one in number of slab tests 2014-07-03 09:21:53 -07:00
sparse-vmemmap.c mm/sparse: use memblock apis for early memory allocations 2014-01-21 16:19:47 -08:00
sparse.c mm: use macros from compiler.h instead of __attribute__((...)) 2014-04-07 16:35:54 -07:00
swap.c mm: non-atomically mark page accessed during page cache allocation where possible 2014-06-04 16:54:10 -07:00
swap_state.c mm: page_alloc: convert hot/cold parameter and immediate callers to bool 2014-06-04 16:54:09 -07:00
swapfile.c mm/swapfile.c: delete the "last_in_cluster < scan_base" loop in the body of scan_swap_map() 2014-06-04 16:54:12 -07:00
truncate.c mm: Remove false WARN_ON from pagecache_isize_extended() 2014-11-13 11:49:03 +00:00
util.c vm_is_stack: use for_each_thread() rather then buggy while_each_thread() 2014-09-05 16:36:43 -07:00
vmacache.c mm,vmacache: optimize overflow system-wide flushing 2014-06-04 16:53:57 -07:00
vmalloc.c mm/vmalloc.c: export unmap_kernel_range() 2014-06-04 16:54:14 -07:00
vmpressure.c mm/vmpressure.c: fix race in vmpressure_work_fn() 2014-12-10 17:49:42 +00:00
vmscan.c mm, vmscan: prevent kswapd livelock due to pfmemalloc-throttled process being killed 2015-01-16 14:34:32 +00:00
vmstat.c mm: use the light version __mod_zone_page_state in mlocked_vma_newpage() 2014-06-04 16:54:07 -07:00
workingset.c mm: keep page cache radix tree nodes in check 2014-04-03 16:21:01 -07:00
zbud.c mm/zbud.c: make size unsigned like unique callsite 2014-06-04 16:54:13 -07:00
zsmalloc.c zsmalloc: fixup trivial zs size classes value in comments 2014-06-04 16:54:13 -07:00
zswap.c mm/zswap: NUMA aware allocation for zswap_dstmem 2014-06-04 16:54:14 -07:00