projects/linux·commit 7966cf0e

PM: hibernate: Fix crash when freeing invalid crypto compressor

7966cf0e · Malaya Kumar Rout <[email protected]> · 2025-12-30 17:26:13 +05:30

When crypto_alloc_acomp() fails, it returns an ERR_PTR value, not NULL.

The cleanup code in save_compressed_image() and load_compressed_image()
unconditionally calls crypto_free_acomp() without checking for ERR_PTR,
which causes crypto_acomp_tfm() to dereference an invalid pointer and
crash the kernel.

This can be triggered when the compression algorithm is unavailable
(e.g., CONFIG_CRYPTO_LZO not enabled).

Fix by adding IS_ERR_OR_NULL() checks before calling crypto_free_acomp()
and acomp_request_free(), similar to the existing kthread_stop() check.

Fixes: b03d542c3c95 ("PM: hibernate: Use crypto_acomp interface")
Signed-off-by: Malaya Kumar Rout <[email protected]>
Cc: 6.15+ <[email protected]> # 6.15+
[ rjw: Added 2 empty code lines ]
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Rafael J. Wysocki <[email protected]>
Commit
7966cf0ebe32c981bfa3db252cb5fc3bb1bf2e77
Parents
9ace4753

Changes

1 files changed · +10 −4

FileStatusAddDelContent
kernel/power/swap.cmodified+10−4View file

kernel/power/swap.c

View file
diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index 33a1863..8050e51 100644
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -902,8 +902,11 @@ out_clean:
for (thr = 0; thr < nr_threads; thr++) {
if (data[thr].thr)
kthread_stop(data[thr].thr);
- acomp_request_free(data[thr].cr);
- crypto_free_acomp(data[thr].cc);
+ if (data[thr].cr)
+ acomp_request_free(data[thr].cr);
+
+ if (!IS_ERR_OR_NULL(data[thr].cc))
+ crypto_free_acomp(data[thr].cc);
}
vfree(data);
}
@@ -1499,8 +1502,11 @@ out_clean:
for (thr = 0; thr < nr_threads; thr++) {
if (data[thr].thr)
kthread_stop(data[thr].thr);
- acomp_request_free(data[thr].cr);
- crypto_free_acomp(data[thr].cc);
+ if (data[thr].cr)
+ acomp_request_free(data[thr].cr);
+
+ if (!IS_ERR_OR_NULL(data[thr].cc))
+ crypto_free_acomp(data[thr].cc);
}
vfree(data);
}