[PATCH 1/2] pstore: don't leave an ERR_PTR in the ramoops zone pointer

[Andrea Parri]

ramoops_init_prz() stores the result of persistent_ram_new() in *prz and
returns the error without clearing it when initialization fails.
ramoops_probe() then cleans up through ramoops_free_przs(), which hands
*prz to persistent_ram_free(); that treats the ERR_PTR as a valid zone
and dereferences it, crashing the kernel.

Clear *prz before returning so that cleanup sees a NULL zone.

Fixes: b5d38e9bf1b0c ("pstore/ram: Add console messages handling")
Cc: stable@xxxxxxxxxxxxxxx
Assisted-by: LLM
Signed-off-by: Andrea Parri <parri.andrea@xxxxxxxxx>
---
 fs/pstore/ram.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c
index 2eb0d4fa21869..aa056d0395a4d 100644
--- a/fs/pstore/ram.c
+++ b/fs/pstore/ram.c
@@ -604,6 +604,7 @@ static int ramoops_init_prz(const char *name,
 	if (IS_ERR(*prz)) {
 		int err = PTR_ERR(*prz);
 
+		*prz = NULL;
 		dev_err(dev, "failed to request %s mem region (0x%zx@0x%llx): %d\n",
 			name, sz, (unsigned long long)*paddr, err);
 		return err;
-- 
2.53.0