git: ab639bb28730 - main - libnetmap: reset errno in nmreq_register_decode()

[Vincenzo Maffione]

The branch main has been updated by vmaffione:

URL: https://cgit.FreeBSD.org/src/commit/?id=ab639bb2873034786cd2ec4d2d9c4489fbf6f424

commit ab639bb2873034786cd2ec4d2d9c4489fbf6f424
Author:     Vincenzo Maffione <vmaffione at FreeBSD.org>
AuthorDate: 2021-04-02 14:31:57 +0000
Commit:     Vincenzo Maffione <vmaffione at FreeBSD.org>
CommitDate: 2021-04-02 14:31:57 +0000

    libnetmap: reset errno in nmreq_register_decode()
    
    The reset is necessary at the beginning of the function, because of
    the errno logic in the error path (set errno to EINVAL if not set).
    If errno is already set when calling the function, and the function
    fails, the previous errno value will be inherited.
---
 lib/libnetmap/nmreq.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/libnetmap/nmreq.c b/lib/libnetmap/nmreq.c
index 390f791cb4dd..2c35b3a30089 100644
--- a/lib/libnetmap/nmreq.c
+++ b/lib/libnetmap/nmreq.c
@@ -257,6 +257,8 @@ nmreq_register_decode(const char **pifname, struct nmreq_register *r, struct nmc
 	uint16_t nr_ringid;
 	uint64_t nr_flags;
 
+	errno = 0;
+
 	/* fill the request */
 
 	p_state = P_START;