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kernel
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linux
um: uml_dup_mmap() relies on ->mmap_sem being held, but activate_mm() doesn't hold it
... while calling uml_dup_mmap()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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arch/um/include/asm/mmu_context.h
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arch/um/include/asm/mmu_context.h
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#include <linux/sched.h>
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#include <asm/mmu.h>
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extern void arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm);
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extern void uml_setup_stubs(struct mm_struct *mm);
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extern void arch_exit_mmap(struct mm_struct *mm);
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#define deactivate_mm(tsk,mm) do { } while (0)
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* when the new ->mm is used for the first time.
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*/
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__switch_mm(&new->context.id);
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arch_dup_mmap(old, new);
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down_write(&new->mmap_sem);
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uml_setup_stubs(new);
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up_write(&new->mmap_sem);
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}
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static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
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if(next != &init_mm)
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__switch_mm(&next->context.id);
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}
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}
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static inline void arch_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm)
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{
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uml_setup_stubs(mm);
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}
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static inline void enter_lazy_tlb(struct mm_struct *mm,