Subject: [merged] mm-fix-use-after-free-in-sys_remap_file_pages.patch removed from -mm tree To: riel@xxxxxxxxxx,dvyukov@xxxxxxxxxx,gorcunov@xxxxxxxxxx,hughd@xxxxxxxxxx,keescook@xxxxxxxxxxxx,pageexec@xxxxxxxxxxx,stable@xxxxxxxxxxxxxxx,walken@xxxxxxxxxx,mm-commits@xxxxxxxxxxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx Date: Fri, 03 Jan 2014 12:37:58 -0800 The patch titled Subject: mm: fix use-after-free in sys_remap_file_pages has been removed from the -mm tree. Its filename was mm-fix-use-after-free-in-sys_remap_file_pages.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: Rik van Riel <riel@xxxxxxxxxx> Subject: mm: fix use-after-free in sys_remap_file_pages remap_file_pages calls mmap_region, which may merge the VMA with other existing VMAs, and free "vma". This can lead to a use-after-free bug. Avoid the bug by remembering vm_flags before calling mmap_region, and not trying to dereference vma later. Signed-off-by: Rik van Riel <riel@xxxxxxxxxx> Reported-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Cc: PaX Team <pageexec@xxxxxxxxxxx> Cc: Kees Cook <keescook@xxxxxxxxxxxx> Cc: Michel Lespinasse <walken@xxxxxxxxxx> Cc: Cyrill Gorcunov <gorcunov@xxxxxxxxxx> Cc: Hugh Dickins <hughd@xxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/fremap.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff -puN mm/fremap.c~mm-fix-use-after-free-in-sys_remap_file_pages mm/fremap.c --- a/mm/fremap.c~mm-fix-use-after-free-in-sys_remap_file_pages +++ a/mm/fremap.c @@ -208,9 +208,10 @@ get_write_lock: if (mapping_cap_account_dirty(mapping)) { unsigned long addr; struct file *file = get_file(vma->vm_file); + /* mmap_region may free vma; grab the info now */ + vm_flags = ACCESS_ONCE(vma->vm_flags); - addr = mmap_region(file, start, size, - vma->vm_flags, pgoff); + addr = mmap_region(file, start, size, vm_flags, pgoff); fput(file); if (IS_ERR_VALUE(addr)) { err = addr; @@ -218,7 +219,7 @@ get_write_lock: BUG_ON(addr != start); err = 0; } - goto out; + goto out_freed; } mutex_lock(&mapping->i_mmap_mutex); flush_dcache_mmap_lock(mapping); @@ -253,6 +254,7 @@ get_write_lock: out: if (vma) vm_flags = vma->vm_flags; +out_freed: if (likely(!has_write_lock)) up_read(&mm->mmap_sem); else _ Patches currently in -mm which might be from riel@xxxxxxxxxx are origin.patch mm-hugetlb-use-get_page_foll-in-follow_hugetlb_page.patch mm-hugetlbfs-move-the-put-get_page-slab-and-hugetlbfs-optimization-in-a-faster-path.patch mm-thp-optimize-compound_trans_huge.patch mm-tail-page-refcounting-optimization-for-slab-and-hugetlbfs.patch mm-hugetlbfs-use-__compound_tail_refcounted-in-__get_page_tail-too.patch mm-hugetlbc-simplify-pageheadhuge-and-pagehuge.patch mm-swapc-reorganize-put_compound_page.patch mm-hugetlbc-defer-pageheadhuge-symbol-export.patch proc-meminfo-provide-estimated-available-memory.patch mm-call-mmu-notifiers-when-copying-a-hugetlb-page-range.patch mm-mmapc-add-mlock_future_check-helper.patch mm-mlock-prepare-params-outside-critical-region.patch x86-get-pg_data_ts-memory-from-other-node.patch memblock-numa-introduce-flags-field-into-memblock.patch memblock-mem_hotplug-introduce-memblock_hotplug-flag-to-mark-hotpluggable-regions.patch memblock-make-memblock_set_node-support-different-memblock_type.patch acpi-numa-mem_hotplug-mark-hotpluggable-memory-in-memblock.patch acpi-numa-mem_hotplug-mark-all-nodes-the-kernel-resides-un-hotpluggable.patch memblock-mem_hotplug-make-memblock-skip-hotpluggable-regions-if-needed.patch x86-numa-acpi-memory-hotplug-make-movable_node-have-higher-priority.patch mm-rmap-recompute-pgoff-for-huge-page.patch mm-rmap-factor-nonlinear-handling-out-of-try_to_unmap_file.patch mm-rmap-factor-lock-function-out-of-rmap_walk_anon.patch mm-rmap-make-rmap_walk-to-get-the-rmap_walk_control-argument.patch mm-rmap-extend-rmap_walk_xxx-to-cope-with-different-cases.patch mm-rmap-use-rmap_walk-in-try_to_unmap.patch mm-rmap-use-rmap_walk-in-try_to_munlock.patch mm-rmap-use-rmap_walk-in-page_referenced.patch mm-rmap-use-rmap_walk-in-page_referenced-fix.patch mm-rmap-use-rmap_walk-in-page_mkclean.patch mm-numa-make-numa-migrate-related-functions-static.patch mm-numa-limit-scope-of-lock-for-numa-migrate-rate-limiting.patch mm-numa-trace-tasks-that-fail-migration-due-to-rate-limiting.patch mm-numa-do-not-automatically-migrate-ksm-pages.patch sched-add-tracepoints-related-to-numa-task-migration.patch sched-add-tracepoints-related-to-numa-task-migration-fix.patch mm-compaction-trace-compaction-begin-and-end.patch mm-compaction-encapsulate-defer-reset-logic.patch mm-compaction-reset-cached-scanner-pfns-before-reading-them.patch mm-compaction-detect-when-scanners-meet-in-isolate_freepages.patch mm-compaction-do-not-mark-unmovable-pageblocks-as-skipped-in-async-compaction.patch mm-compaction-reset-scanner-positions-immediately-when-they-meet.patch mm-migrate-add-comment-about-permanent-failure-path.patch mm-migrate-correct-failure-handling-if-hugepage_migration_support.patch mm-migrate-remove-putback_lru_pages-fix-comment-on-putback_movable_pages.patch mm-migrate-remove-unused-function-fail_migrate_page.patch mm-munlock-fix-potential-race-with-thp-page-split.patch mm-remove-bug_on-from-mlock_vma_page.patch swap-add-a-simple-detector-for-inappropriate-swapin-readahead.patch ipc-introduce-ipc_valid_object-helper-to-sort-out-ipc_rmid-races.patch ipc-change-kern_ipc_permdeleted-type-to-bool.patch linux-next.patch mm-migratec-fix-set-cpupid-on-page-migration-twice-against-thp.patch zsmalloc-move-it-under-mm.patch zram-promote-zram-from-staging.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html