6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ekansh Gupta <quic_ekangupt@xxxxxxxxxxx> commit 509143385db364c67556a914bef6c9a42fd2c74c upstream. For unmapping any buffer from kernel, it should first be unmapped from DSP. In case unmap from DSP request fails, the map should not be removed from kernel as it might lead to SMMU faults and other memory issues. Fixes: 5c1b97c7d7b7 ("misc: fastrpc: add support for FASTRPC_IOCTL_MEM_MAP/UNMAP") Cc: stable <stable@xxxxxxxxxx> Signed-off-by: Ekansh Gupta <quic_ekangupt@xxxxxxxxxxx> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx> Link: https://lore.kernel.org/r/20231013122007.174464-5-srinivas.kandagatla@xxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/misc/fastrpc.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) --- a/drivers/misc/fastrpc.c +++ b/drivers/misc/fastrpc.c @@ -1783,11 +1783,13 @@ static int fastrpc_req_mem_unmap_impl(st sc = FASTRPC_SCALARS(FASTRPC_RMID_INIT_MEM_UNMAP, 1, 0); err = fastrpc_internal_invoke(fl, true, FASTRPC_INIT_HANDLE, sc, &args[0]); - fastrpc_map_put(map); - if (err) + if (err) { dev_err(dev, "unmmap\tpt fd = %d, 0x%09llx error\n", map->fd, map->raddr); + return err; + } + fastrpc_map_put(map); - return err; + return 0; } static int fastrpc_req_mem_unmap(struct fastrpc_user *fl, char __user *argp)