octeontx2-af: Fix a memleak bug in rvu_mbox_init()

BugLink: https://bugs.launchpad.net/bugs/1953731
commit e07a097b4986afb8f925d0bb32612e1d3e88ce15 upstream.

In rvu_mbox_init(), mbox_regions is not freed or passed out
under the switch-default region, which could lead to a memory leak.

Fix this bug by changing 'return err' to 'goto free_regions'.

This bug was found by a static analyzer. The analysis employs
differential checking to identify inconsistent security operations
(e.g., checks or kfrees) between two code paths and confirms that the
inconsistent operations are not recovered in the current function or
the callers, so they constitute bugs.

Note that, as a bug found by static analysis, it can be a false
positive or hard to trigger. Multiple researchers have cross-reviewed
the bug.

Builds with CONFIG_OCTEONTX2_AF=y show no new warnings,
and our static analyzer no longer warns about this code.

Fixes: 98c561116360 (“octeontx2-af: cn10k: Add mbox support for CN10K platform”)
Signed-off-by: Zhou Qingyang <zhou1615@umn.edu>
Link: https://lore.kernel.org/r/20211130165039.192426-1-zhou1615@umn.edu
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>

diff --git a/drivers/net/ethernet/marvell/octeontx2/af/rvu.c b/drivers/net/ethernet/marvell/octeontx2/af/rvu.c
index 35836903b7fbc3137f82b21809f1c561978c283b..90dc5343827f0e5ac12bffedd4b1a90340bd6b50 100644 (file)
--- a/drivers/net/ethernet/marvell/octeontx2/af/rvu.c
+++ b/drivers/net/ethernet/marvell/octeontx2/af/rvu.c
@@ -2281,7 +2281,7 @@ static int rvu_mbox_init(struct rvu *rvu, struct mbox_wq_info *mw,
                        goto free_regions;
                break;
        default:
-               return err;
+               goto free_regions;
        }
 
        mw->mbox_wq = alloc_workqueue(name,