PM: hibernate: Use atomic64_t for compressed_size variable

`compressed_size` can overflow, showing nonsensical values.

Change from `atomic_t` to `atomic64_t` to prevent overflow.

Fixes: a06c6f5d3cc9 ("PM: hibernate: Move to crypto APIs for LZO compression")
Reported-by: Askar Safin <safinaskar@gmail.com>
Closes: https://lore.kernel.org/linux-pm/20251105180506.137448-1-safinaskar@gmail.com/
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
Tested-by: Askar Safin <safinaskar@gmail.com>
Cc: 6.9+ <stable@vger.kernel.org> # 6.9+
Link: https://patch.msgid.link/20251106045158.3198061-3-superm1@kernel.org
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index 7daa716d2cb13138c3b16f21b8c7b4aaa3969a94..e0441483dbee748fd7be3135eb9be7227a28d7a7 100644 (file)
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -635,7 +635,7 @@ struct cmp_data {
 };
 
 /* Indicates the image size after compression */
-static atomic_t compressed_size = ATOMIC_INIT(0);
+static atomic64_t compressed_size = ATOMIC_INIT(0);
 
 /*
  * Compression function that runs in its own thread.
@@ -664,7 +664,7 @@ static int compress_threadfn(void *data)
                d->ret = crypto_acomp_compress(d->cr);
                d->cmp_len = d->cr->dlen;
 
-               atomic_set(&compressed_size, atomic_read(&compressed_size) + d->cmp_len);
+               atomic64_add(d->cmp_len, &compressed_size);
                atomic_set_release(&d->stop, 1);
                wake_up(&d->done);
        }
@@ -696,7 +696,7 @@ static int save_compressed_image(struct swap_map_handle *handle,
 
        hib_init_batch(&hb);
 
-       atomic_set(&compressed_size, 0);
+       atomic64_set(&compressed_size, 0);
 
        /*
         * We'll limit the number of threads for compression to limit memory
@@ -879,8 +879,8 @@ out_finish:
                ret = err2;
        if (!ret) {
                swsusp_show_speed(start, stop, nr_to_write, "Wrote");
-               pr_info("Image size after compression: %d kbytes\n",
-                       (atomic_read(&compressed_size) / 1024));
+               pr_info("Image size after compression: %lld kbytes\n",
+                       (atomic64_read(&compressed_size) / 1024));
                pr_info("Image saving done\n");
        } else {
                pr_err("Image saving failed: %d\n", ret);