[PATCH] PM: hibernate: Fix potential memory leak in hibernate_preallocate_memory() and prepare_highmem_image()

From: Jianglei Nie
Date: Mon Sep 05 2022 - 04:38:04 EST


hibernate_preallocate_memory() and prepare_highmem_image() allocates
memory chunk with memory_bm_create(). When the function gets some error
after memory_bm_create(), relavent memory should be released with
memory_bm_free().

Fix it by calling memory_bm_free() at the right time.

Signed-off-by: Jianglei Nie <niejianglei2021@xxxxxxx>
---
kernel/power/snapshot.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index 2a406753af90..15345ad0b319 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -1752,6 +1752,7 @@ int hibernate_preallocate_memory(void)

error = memory_bm_create(&copy_bm, GFP_IMAGE, PG_ANY);
if (error) {
+ memory_bm_free(orig_bm, PG_UNSAFE_CLEAR);
pr_err("Cannot allocate copy bitmap\n");
goto err_out;
}
@@ -2335,8 +2336,10 @@ static int prepare_highmem_image(struct memory_bitmap *bm,
if (memory_bm_create(bm, GFP_ATOMIC, PG_SAFE))
return -ENOMEM;

- if (get_highmem_buffer(PG_SAFE))
+ if (get_highmem_buffer(PG_SAFE)) {
+ memory_bm_free(bm, PG_UNSAFE_CLEAR);
return -ENOMEM;
+ }

to_alloc = count_free_highmem_pages();
if (to_alloc > *nr_highmem_p)
--
2.25.1