Unverified Commit 29f7045c authored by openeuler-ci-bot's avatar openeuler-ci-bot Committed by Gitee
Browse files

!15681 kernel: be more careful about dup_mmap() failures and uprobe registering 

Merge Pull Request from: @ci-robot 
 
PR sync from: Zicheng Qu <quzicheng@huawei.com>
https://mailweb.openeuler.org/archives/list/kernel@openeuler.org/message/ZUQ3TW4MZQ6IVLCGYRJ3VJFMFHYAVBDD/ 
 
https://gitee.com/src-openeuler/kernel/issues/IBPBM0 
 
Link:https://gitee.com/openeuler/kernel/pulls/15681

 

Reviewed-by: default avatarLu Jialin <lujialin4@huawei.com>
Signed-off-by: default avatarZhang Peng <zhangpeng362@huawei.com>
parents 7ee7efdc e811c4e3

kernel/events/uprobes.c

+4 −0
Original line number Diff line number Diff line
@@ -26,6 +26,7 @@ 
#include <linux/task_work.h>

#include <linux/shmem_fs.h>

#include <linux/khugepaged.h>

#include <linux/oom.h>          /* check_stable_address_space */



#include <linux/uprobes.h>
@@ -1055,6 +1056,9 @@ register_for_each_vma(struct uprobe *uprobe, struct uprobe_consumer *new) 
			goto free;



		mmap_write_lock(mm);

		if (check_stable_address_space(mm))

			goto unlock;



		vma = find_vma(mm, info->vaddr);

		if (!vma || !valid_vma(vma, is_register) ||

		    file_inode(vma->vm_file) != uprobe->inode)

kernel/fork.c

+14 −3
Original line number Diff line number Diff line
@@ -794,7 +794,8 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, 
		mt_set_in_rcu(vmi.mas.tree);

		ksm_fork(mm, oldmm);

		khugepaged_fork(mm, oldmm);

	} else if (mpnt) {

	} else {



		/*

		 * The entire maple tree has already been duplicated. If the

		 * mmap duplication fails, mark the failure point with
@@ -802,8 +803,18 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, 
		 * stop releasing VMAs that have not been duplicated after this

		 * point.

		 */

		if (mpnt) {

			mas_set_range(&vmi.mas, mpnt->vm_start, mpnt->vm_end - 1);

			mas_store(&vmi.mas, XA_ZERO_ENTRY);

			/* Avoid OOM iterating a broken tree */

			set_bit(MMF_OOM_SKIP, &mm->flags);

		}

		/*

		 * The mm_struct is going to exit, but the locks will be dropped

		 * first.  Set the mm_struct as unstable is advisable as it is

		 * not fully initialised.

		 */

		set_bit(MMF_UNSTABLE, &mm->flags);

	}

out:

	mmap_write_unlock(mm);