6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Sukrut Bellary sukrut.bellary@linux.com
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@linuxfoundation.org Reviewed-by: Dan Carpenter dan.carpenter@linaro.org Reviewed-by: Srinivas Kandagatla srinivas.kandagatla@linaro.org Signed-off-by: Sukrut Bellary sukrut.bellary@linux.com Signed-off-by: Srinivas Kandagatla srinivas.kandagatla@linaro.org Cc: stable stable@kernel.org Link: https://lore.kernel.org/r/20240902141409.70371-2-srinivas.kandagatla@linaro.... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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; }