This code calls kfree(bfr); and then passes "bfr" to rtk->ops->crashed()
which is a use after free. The ->crashed function pointer is implemented
by apple_nvme_rtkit_crashed() and it doesn't use the "bfr" pointer so
this doesn't cause a problem. But it still looks sketchy as can be.
Fix this by moving kfree() after the last usage of bfr.
Fixes: c559645f343a ("soc: apple: rtkit: Pass the crashlog to the crashed() callback")
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@xxxxxxxxxx>
---
This is based on static analysis with smatch, only compile tested.
---
drivers/soc/apple/rtkit.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/soc/apple/rtkit.c b/drivers/soc/apple/rtkit.c
index 4b0783091a92..1ccec7ba640c 100644
--- a/drivers/soc/apple/rtkit.c
+++ b/drivers/soc/apple/rtkit.c
@@ -360,7 +360,6 @@ static void apple_rtkit_crashlog_rx(struct apple_rtkit *rtk, u64 msg)
apple_rtkit_memcpy(rtk, bfr, &rtk->crashlog_buffer, 0,
rtk->crashlog_buffer.size);
apple_rtkit_crashlog_dump(rtk, bfr, rtk->crashlog_buffer.size);
- kfree(bfr);
} else {
dev_err(rtk->dev,
"RTKit: Couldn't allocate crashlog shadow buffer\n");
@@ -369,6 +368,8 @@ static void apple_rtkit_crashlog_rx(struct apple_rtkit *rtk, u64 msg)
rtk->crashed = true;
if (rtk->ops->crashed)
rtk->ops->crashed(rtk->cookie, bfr, rtk->crashlog_buffer.size);
+
+ kfree(bfr);
}
static void apple_rtkit_ioreport_rx(struct apple_rtkit *rtk, u64 msg)
--
2.39.3
