The patch titled
Subject: mm/mmap: fix leak on expand_downwards() and expand_upwards()
has been added to the -mm mm-unstable branch. Its filename is
mm-start-tracking-vmas-with-maple-tree-fix-2.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-start-tracking-vmas-with-maple-tree-fix-2.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Liam Howlett <liam.howlett@xxxxxxxxxx>
Subject: mm/mmap: fix leak on expand_downwards() and expand_upwards()
A memory leak is possible in the race and error path in both
expand_downwards() and expand_upwards() due to the maple tree
preallocations. Fix these by always destroying the maple state.
Link: https://lkml.kernel.org/r/20220512175915.1814885-1-Liam.Howlett@xxxxxxxxxx
Fixes: a760774e7b7b (mm: start tracking VMAs with maple tree)
Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
Reported-by: Qian Cai <quic_qiancai@xxxxxxxxxxx>
Cc: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/mmap.c | 2 ++
1 file changed, 2 insertions(+)
--- a/mm/mmap.c~mm-start-tracking-vmas-with-maple-tree-fix-2
+++ a/mm/mmap.c
@@ -2664,6 +2664,7 @@ int expand_upwards(struct vm_area_struct
khugepaged_enter_vma_merge(vma, vma->vm_flags);
validate_mm(mm);
validate_mm_mt(mm);
+ mas_destroy(&mas);
return error;
}
#endif /* CONFIG_STACK_GROWSUP || CONFIG_IA64 */
@@ -2751,6 +2752,7 @@ int expand_downwards(struct vm_area_stru
anon_vma_unlock_write(vma->anon_vma);
khugepaged_enter_vma_merge(vma, vma->vm_flags);
validate_mm(mm);
+ mas_destroy(&mas);
return error;
}
_
Patches currently in -mm which might be from liam.howlett@xxxxxxxxxx are
maple-tree-add-new-data-structure-fix.patch
lib-test_maple_tree-add-testing-for-maple-tree-fix.patch
mm-start-tracking-vmas-with-maple-tree-fix-2.patch
