6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Sukrut Bellary <sukrut.bellary@xxxxxxxxx>
commit e8c276d4dc0e19ee48385f74426aebc855b49aaf upstream.
smatch warning:
drivers/misc/fastrpc.c:1926 fastrpc_req_mmap() error: double free of 'buf'
In fastrpc_req_mmap() error path, the fastrpc buffer is freed in
fastrpc_req_munmap_impl() if unmap is successful.
But in the end, there is an unconditional call to fastrpc_buf_free().
So the above case triggers the double free of fastrpc buf.
Fixes: 72fa6f7820c4 ("misc: fastrpc: Rework fastrpc_req_munmap")
Reviewed-by: Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>
Reviewed-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
Signed-off-by: Sukrut Bellary <sukrut.bellary@xxxxxxxxx>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
Cc: stable <stable@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240902141409.70371-2-srinivas.kandagatla@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/misc/fastrpc.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
--- a/drivers/misc/fastrpc.c
+++ b/drivers/misc/fastrpc.c
@@ -1912,7 +1912,8 @@ static int fastrpc_req_mmap(struct fastr
&args[0]);
if (err) {
dev_err(dev, "mmap error (len 0x%08llx)\n", buf->size);
- goto err_invoke;
+ fastrpc_buf_free(buf);
+ return err;
}
/* update the buffer to be able to deallocate the memory on the DSP */
@@ -1950,8 +1951,6 @@ static int fastrpc_req_mmap(struct fastr
err_assign:
fastrpc_req_munmap_impl(fl, buf);
-err_invoke:
- fastrpc_buf_free(buf);
return err;
}
