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| author | Konstantin Khlebnikov <khlebnikov@yandex-team.ru> | 2018-01-31 16:17:22 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-01-31 17:18:37 -0800 |
| commit | 8526d84f81710c77ead9a7bfe82b66a241f1aed1 (patch) | |
| tree | 8db932a559d9f02c5fd293150117b7e33f00af21 | |
| parent | ef549e13cf62733097eb1f7a9f44b2cea1611007 (diff) | |
| download | linux-8526d84f81710c77ead9a7bfe82b66a241f1aed1.tar.gz | |
fs/proc/task_mmu.c: do not show VmExe bigger than total executable virtual memory
If start_code / end_code pointers are screwed then "VmExe" could be bigger than total executable virtual memory and "VmLib" becomes negative: VmExe: 294320 kB VmLib: 18446744073709327564 kB VmExe and VmLib documented as text segment and shared library code size. Now their sum will be always equal to mm->exec_vm which sums size of executable and not writable and not stack areas. I've seen this for huge (>2Gb) statically linked binary which has whole world inside. For it start_code .. end_code range also covers one of rodata sections. Probably this is bug in customized linker, elf loader or both. Anyway CONFIG_CHECKPOINT_RESTORE allows to change these pointers, thus we cannot trust them without validation. Link: http://lkml.kernel.org/r/150728955451.743749.11276392315459539583.stgit@buzz Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Acked-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | fs/proc/task_mmu.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 339e4c1c044d..4691f5aca00e 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -47,8 +47,11 @@ void task_mem(struct seq_file *m, struct mm_struct *mm) if (hiwater_rss < mm->hiwater_rss) hiwater_rss = mm->hiwater_rss; - text = (PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK)) >> 10; - lib = (mm->exec_vm << (PAGE_SHIFT-10)) - text; + /* split executable areas between text and lib */ + text = PAGE_ALIGN(mm->end_code) - (mm->start_code & PAGE_MASK); + text = min(text, mm->exec_vm << PAGE_SHIFT); + lib = (mm->exec_vm << PAGE_SHIFT) - text; + swap = get_mm_counter(mm, MM_SWAPENTS); seq_printf(m, "VmPeak:\t%8lu kB\n" @@ -76,7 +79,9 @@ void task_mem(struct seq_file *m, struct mm_struct *mm) file << (PAGE_SHIFT-10), shmem << (PAGE_SHIFT-10), mm->data_vm << (PAGE_SHIFT-10), - mm->stack_vm << (PAGE_SHIFT-10), text, lib, + mm->stack_vm << (PAGE_SHIFT-10), + text >> 10, + lib >> 10, mm_pgtables_bytes(mm) >> 10, swap << (PAGE_SHIFT-10)); hugetlb_report_usage(m, mm); |