* [dpdk-stable] [PATCH 16.11] vhost-user: fix false negative in handling user messages @ 2018-11-28 16:20 ` Luca Boccassi 2018-11-29 7:58 ` Ilya Maximets 2018-11-29 8:49 ` Maxime Coquelin 0 siblings, 2 replies; 4+ messages in thread From: Luca Boccassi @ 2018-11-28 16:20 UTC (permalink / raw) To: stable; +Cc: i.maximets, maxime.coquelin vhost_user_msg_handler checks an accumulated return code before returning, and prints an error and returns -1 if it's non-zero. But some of the possible user messages cannot fail and thus do not set the variable, which might retain a previously set and unrelated value, causing unnecessary failures and error messages. Reset the return code before use. Fixes: 0ce9e73d1e8d ("vhost-user: drop connection on message handling failures") Signed-off-by: Luca Boccassi <bluca@debian.org> --- Found this issue when testing with the Vyatta stuff, "ret" is set at the beginning of the function and never reset when the message is for example VHOST_USER_GET_FEATURES so there's a flurry of errors. lib/librte_vhost/vhost_user.c | 1 + 1 file changed, 1 insertion(+) diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c index 00872c868..618d413fe 100644 --- a/lib/librte_vhost/vhost_user.c +++ b/lib/librte_vhost/vhost_user.c @@ -1087,6 +1087,7 @@ vhost_user_msg_handler(int vid, int fd) } + ret = 0; switch (msg.request) { case VHOST_USER_GET_FEATURES: msg.payload.u64 = vhost_user_get_features(); -- 2.19.2 ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [dpdk-stable] [PATCH 16.11] vhost-user: fix false negative in handling user messages 2018-11-28 16:20 ` [dpdk-stable] [PATCH 16.11] vhost-user: fix false negative in handling user messages Luca Boccassi @ 2018-11-29 7:58 ` Ilya Maximets 2018-11-29 10:45 ` Luca Boccassi 2018-11-29 8:49 ` Maxime Coquelin 1 sibling, 1 reply; 4+ messages in thread From: Ilya Maximets @ 2018-11-29 7:58 UTC (permalink / raw) To: Luca Boccassi, stable; +Cc: maxime.coquelin On 28.11.2018 19:20, Luca Boccassi wrote: > vhost_user_msg_handler checks an accumulated return code before > returning, and prints an error and returns -1 if it's non-zero. > But some of the possible user messages cannot fail and thus do not > set the variable, which might retain a previously set and unrelated > value, causing unnecessary failures and error messages. > > Reset the return code before use. > > Fixes: 0ce9e73d1e8d ("vhost-user: drop connection on message handling failures") > > Signed-off-by: Luca Boccassi <bluca@debian.org> > --- > Found this issue when testing with the Vyatta stuff, "ret" is set at > the beginning of the function and never reset when the message is for example > VHOST_USER_GET_FEATURES so there's a flurry of errors. Hmm. Yes, current implementation in 16.11 branch doesn't work at all. I think that it's a kind of an issue in the original patch 0d7853a4d. But it uncovered only after backporting. On master we had additional call 'ret = vhost_user_check_and_alloc_queue_pair()' before the main handling switch and this function could only return 0 or -1. So, the 'ret' was always zero if we reached the handling switch. LGTM, Acked-by: Ilya Maximets <i.maximets@samsung.com> > > lib/librte_vhost/vhost_user.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c > index 00872c868..618d413fe 100644 > --- a/lib/librte_vhost/vhost_user.c > +++ b/lib/librte_vhost/vhost_user.c > @@ -1087,6 +1087,7 @@ vhost_user_msg_handler(int vid, int fd) > > } > > + ret = 0; > switch (msg.request) { > case VHOST_USER_GET_FEATURES: > msg.payload.u64 = vhost_user_get_features(); > ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [dpdk-stable] [PATCH 16.11] vhost-user: fix false negative in handling user messages 2018-11-29 7:58 ` Ilya Maximets @ 2018-11-29 10:45 ` Luca Boccassi 0 siblings, 0 replies; 4+ messages in thread From: Luca Boccassi @ 2018-11-29 10:45 UTC (permalink / raw) To: Ilya Maximets, stable; +Cc: maxime.coquelin On Thu, 2018-11-29 at 10:58 +0300, Ilya Maximets wrote: > On 28.11.2018 19:20, Luca Boccassi wrote: > > vhost_user_msg_handler checks an accumulated return code before > > returning, and prints an error and returns -1 if it's non-zero. > > But some of the possible user messages cannot fail and thus do not > > set the variable, which might retain a previously set and unrelated > > value, causing unnecessary failures and error messages. > > > > Reset the return code before use. > > > > Fixes: 0ce9e73d1e8d ("vhost-user: drop connection on message > > handling failures") > > > > Signed-off-by: Luca Boccassi <bluca@debian.org> > > --- > > Found this issue when testing with the Vyatta stuff, "ret" is set > > at > > the beginning of the function and never reset when the message is > > for example > > VHOST_USER_GET_FEATURES so there's a flurry of errors. > > Hmm. Yes, current implementation in 16.11 branch doesn't work at all. > I think that it's a kind of an issue in the original patch 0d7853a4d. > But it uncovered only after backporting. On master we had additional > call 'ret = vhost_user_check_and_alloc_queue_pair()' before the main > handling switch and this function could only return 0 or -1. So, the > 'ret' was always zero if we reached the handling switch. > > LGTM, > Acked-by: Ilya Maximets <i.maximets@samsung.com> I see. Thank you both for the reviews, applied and pushed. -- Kind regards, Luca Boccassi ^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [dpdk-stable] [PATCH 16.11] vhost-user: fix false negative in handling user messages 2018-11-28 16:20 ` [dpdk-stable] [PATCH 16.11] vhost-user: fix false negative in handling user messages Luca Boccassi 2018-11-29 7:58 ` Ilya Maximets @ 2018-11-29 8:49 ` Maxime Coquelin 1 sibling, 0 replies; 4+ messages in thread From: Maxime Coquelin @ 2018-11-29 8:49 UTC (permalink / raw) To: Luca Boccassi, stable; +Cc: i.maximets On 11/28/18 5:20 PM, Luca Boccassi wrote: > vhost_user_msg_handler checks an accumulated return code before > returning, and prints an error and returns -1 if it's non-zero. > But some of the possible user messages cannot fail and thus do not > set the variable, which might retain a previously set and unrelated > value, causing unnecessary failures and error messages. > > Reset the return code before use. > > Fixes: 0ce9e73d1e8d ("vhost-user: drop connection on message handling failures") > > Signed-off-by: Luca Boccassi <bluca@debian.org> > --- > Found this issue when testing with the Vyatta stuff, "ret" is set at > the beginning of the function and never reset when the message is for example > VHOST_USER_GET_FEATURES so there's a flurry of errors. > > lib/librte_vhost/vhost_user.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c > index 00872c868..618d413fe 100644 > --- a/lib/librte_vhost/vhost_user.c > +++ b/lib/librte_vhost/vhost_user.c > @@ -1087,6 +1087,7 @@ vhost_user_msg_handler(int vid, int fd) > > } > > + ret = 0; > switch (msg.request) { > case VHOST_USER_GET_FEATURES: > msg.payload.u64 = vhost_user_get_features(); > Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com> Thanks! Maxime ^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2018-11-29 10:45 UTC | newest] Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- [not found] <CGME20181128162145epcas4p37815583a5bc1574c266eb8afb73d92c6@epcas4p3.samsung.com> 2018-11-28 16:20 ` [dpdk-stable] [PATCH 16.11] vhost-user: fix false negative in handling user messages Luca Boccassi 2018-11-29 7:58 ` Ilya Maximets 2018-11-29 10:45 ` Luca Boccassi 2018-11-29 8:49 ` Maxime Coquelin
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