The patch titled
Subject: mm: cma: fix potential null dereference on pointer cma
has been added to the -mm tree. Its filename is
mm-cma-support-sysfs-fix.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-cma-support-sysfs-fix.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-cma-support-sysfs-fix.patch
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------------------------------------------------------
From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
Subject: mm: cma: fix potential null dereference on pointer cma
At the start of the function there is a null pointer check on cma and then
branch to error handling label 'out'. The subsequent call to
cma_sysfs_fail_pages_count dereferences cma, hence there is a potential
null pointer deference issue. Fix this by only calling
cma_sysfs_fail_pages_count if cma is not null.
Addresses-Coverity: ("Dereference after null check")
Link: https://lkml.kernel.org/r/20210316100433.17665-1-colin.king@xxxxxxxxxxxxx
Fixes: dc4764f7e9ac ("mm: cma: support sysfs")
Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
Acked-by: Minchan Kim <minchan@xxxxxxxxxx>
Reviewed-by: John Hubbard <jhubbard@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/cma.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/mm/cma.c~mm-cma-support-sysfs-fix
+++ a/mm/cma.c
@@ -512,7 +512,8 @@ out:
cma_sysfs_alloc_pages_count(cma, count);
} else {
count_vm_event(CMA_ALLOC_FAIL);
- cma_sysfs_fail_pages_count(cma, count);
+ if (cma)
+ cma_sysfs_fail_pages_count(cma, count);
}
return page;
_
Patches currently in -mm which might be from colin.king@xxxxxxxxxxxxx are
mm-slab-fix-spelling-mistake-disired-desired.patch
mm-cma-support-sysfs-fix.patch
