From: Arnd Bergmann <arnd@arndb.de>
To: stable@vger.kernel.org
Cc: Greg KH <gregkh@linuxfoundation.org>,
linux-kernel@vger.kernel.org, Arnd Bergmann <arnd@arndb.de>,
Ladi Prosek <lprosek@redhat.com>,
"Michael S . Tsirkin" <mst@redhat.com>,
virtualization@lists.linux-foundation.org
Subject: [4.4-stable 12/22] virtio_balloon: prevent uninitialized variable use
Date: Tue, 20 Feb 2018 12:54:59 +0100 [thread overview]
Message-ID: <20180220115527.1806578-13-arnd@arndb.de> (raw)
In-Reply-To: <20180220115527.1806578-1-arnd@arndb.de>
commit f0bb2d50dfcc519f06f901aac88502be6ff1df2c upstream.
The latest gcc-7.0.1 snapshot reports a new warning:
virtio/virtio_balloon.c: In function 'update_balloon_stats':
virtio/virtio_balloon.c:258:26: error: 'events[2]' is used uninitialized in this function [-Werror=uninitialized]
virtio/virtio_balloon.c:260:26: error: 'events[3]' is used uninitialized in this function [-Werror=uninitialized]
virtio/virtio_balloon.c:261:56: error: 'events[18]' is used uninitialized in this function [-Werror=uninitialized]
virtio/virtio_balloon.c:262:56: error: 'events[17]' is used uninitialized in this function [-Werror=uninitialized]
This seems absolutely right, so we should add an extra check to
prevent copying uninitialized stack data into the statistics.
>From all I can tell, this has been broken since the statistics code
was originally added in 2.6.34.
Fixes: 9564e138b1f6 ("virtio: Add memory statistics reporting to the balloon driver (V4)")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
[arnd: backported to 4.4]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
drivers/virtio/virtio_balloon.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index 01d15dca940e..26d0dff069f0 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -239,12 +239,15 @@ static void update_balloon_stats(struct virtio_balloon *vb)
all_vm_events(events);
si_meminfo(&i);
+
+#ifdef CONFIG_VM_EVENT_COUNTERS
update_stat(vb, idx++, VIRTIO_BALLOON_S_SWAP_IN,
pages_to_bytes(events[PSWPIN]));
update_stat(vb, idx++, VIRTIO_BALLOON_S_SWAP_OUT,
pages_to_bytes(events[PSWPOUT]));
update_stat(vb, idx++, VIRTIO_BALLOON_S_MAJFLT, events[PGMAJFAULT]);
update_stat(vb, idx++, VIRTIO_BALLOON_S_MINFLT, events[PGFAULT]);
+#endif
update_stat(vb, idx++, VIRTIO_BALLOON_S_MEMFREE,
pages_to_bytes(i.freeram));
update_stat(vb, idx++, VIRTIO_BALLOON_S_MEMTOT,
--
2.9.0
next prev parent reply other threads:[~2018-02-20 11:54 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-02-20 11:54 [4.4-stable 00/22] patches for 'randconfig' Arnd Bergmann
2018-02-20 11:54 ` [4.4-stable 01/22] gpio: xgene: mark PM functions as __maybe_unused Arnd Bergmann
2018-02-20 11:54 ` [4.4-stable 02/22] Revert "power: bq27xxx_battery: Remove unneeded dependency in Kconfig" Arnd Bergmann
2018-02-20 11:54 ` [4.4-stable 03/22] power: bq27xxx_battery: mark some symbols __maybe_unused Arnd Bergmann
2018-02-20 11:54 ` [4.4-stable 04/22] isdn: sc: work around type mismatch warning Arnd Bergmann
2018-02-20 11:54 ` [4.4-stable 05/22] binfmt_elf: compat: avoid unused function warning Arnd Bergmann
2018-02-20 11:54 ` [4.4-stable 06/22] idle: i7300: add PCI dependency Arnd Bergmann
2018-02-20 11:54 ` [4.4-stable 07/22] usb: phy: msm add regulator dependency Arnd Bergmann
2018-02-20 11:54 ` [4.4-stable 08/22] ncr5380: shut up gcc indentation warning Arnd Bergmann
2018-02-20 22:44 ` Finn Thain
2018-02-20 11:54 ` [4.4-stable 09/22] ARM: tegra: select USB_ULPI from EHCI rather than platform Arnd Bergmann
2018-02-20 11:54 ` [4.4-stable 10/22] ASoC: Intel: Kconfig: fix build when ACPI is not enabled Arnd Bergmann
2018-02-20 11:54 ` [4.4-stable 11/22] netlink: fix nla_put_{u8,u16,u32} for KASAN Arnd Bergmann
2018-02-20 11:54 ` Arnd Bergmann [this message]
2018-02-20 11:55 ` [4.4-stable 13/22] dell-wmi, dell-laptop: depends DMI Arnd Bergmann
2018-02-20 11:55 ` [4.4-stable 14/22] genksyms: Fix segfault with invalid declarations Arnd Bergmann
2018-02-20 11:55 ` [4.4-stable 15/22] perf/x86: Shut up false-positive -Wmaybe-uninitialized warning Arnd Bergmann
2018-02-20 11:55 ` [4.4-stable 16/22] dmaengine: zx: fix build warning Arnd Bergmann
2018-02-20 11:55 ` [4.4-stable 17/22] cw1200: fix bogus maybe-uninitialized warning Arnd Bergmann
2018-02-20 11:55 ` [4.4-stable 18/22] x86/microcode/AMD: Change load_microcode_amd()'s param to bool to fix preemptibility bug Arnd Bergmann
2018-02-20 11:55 ` [4.4-stable 19/22] net: hp100: remove unnecessary #ifdefs Arnd Bergmann
2018-02-20 11:55 ` [4.4-stable 20/22] ncpfs: fix unused variable warning Arnd Bergmann
2018-02-20 11:55 ` [4.4-stable 21/22] drm/gma500: remove helper function Arnd Bergmann
2018-02-20 11:55 ` [4.4-stable 22/22] kasan: rework Kconfig settings Arnd Bergmann
2018-02-23 16:18 ` [4.4-stable 00/22] patches for 'randconfig' Greg KH
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20180220115527.1806578-13-arnd@arndb.de \
--to=arnd@arndb.de \
--cc=gregkh@linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=lprosek@redhat.com \
--cc=mst@redhat.com \
--cc=stable@vger.kernel.org \
--cc=virtualization@lists.linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®