From 38faa2b54663f253cdb18f414f13b249b346d767 Mon Sep 17 00:00:00 2001 From: Leo Famulari Date: Tue, 28 Nov 2017 16:53:07 -0500 Subject: gnu: qemu: Fix CVE-2017-{15118,15119}. * gnu/packages/patches/qemu-CVE-2017-15118.patch, gnu/packages/patches/qemu-CVE-2017-15119.patch: New files. * gnu/local.mk (dist_patch_DATA): Add them. * gnu/packages/virtualization.scm (qemu)[source]: Use them. --- gnu/packages/patches/qemu-CVE-2017-15118.patch | 58 ++++++++++++++++++++++++++ 1 file changed, 58 insertions(+) create mode 100644 gnu/packages/patches/qemu-CVE-2017-15118.patch (limited to 'gnu/packages/patches/qemu-CVE-2017-15118.patch') diff --git a/gnu/packages/patches/qemu-CVE-2017-15118.patch b/gnu/packages/patches/qemu-CVE-2017-15118.patch new file mode 100644 index 0000000000..d427317be9 --- /dev/null +++ b/gnu/packages/patches/qemu-CVE-2017-15118.patch @@ -0,0 +1,58 @@ +Fix CVE-2017-15118: + +https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-15118 +https://bugzilla.redhat.com/show_bug.cgi?id=1516922 + +Patch copied from upstream source repository: + +https://git.qemu.org/?p=qemu.git;a=commitdiff;h=51ae4f8455c9e32c54770c4ebc25bf86a8128183 + +From 51ae4f8455c9e32c54770c4ebc25bf86a8128183 Mon Sep 17 00:00:00 2001 +From: Eric Blake +Date: Wed, 22 Nov 2017 15:07:22 -0600 +Subject: [PATCH] nbd/server: CVE-2017-15118 Stack smash on large export name + +Introduced in commit f37708f6b8 (2.10). The NBD spec says a client +can request export names up to 4096 bytes in length, even though +they should not expect success on names longer than 256. However, +qemu hard-codes the limit of 256, and fails to filter out a client +that probes for a longer name; the result is a stack smash that can +potentially give an attacker arbitrary control over the qemu +process. + +The smash can be easily demonstrated with this client: +$ qemu-io f raw nbd://localhost:10809/$(printf %3000d 1 | tr ' ' a) + +If the qemu NBD server binary (whether the standalone qemu-nbd, or +the builtin server of QMP nbd-server-start) was compiled with +-fstack-protector-strong, the ability to exploit the stack smash +into arbitrary execution is a lot more difficult (but still +theoretically possible to a determined attacker, perhaps in +combination with other CVEs). Still, crashing a running qemu (and +losing the VM) is bad enough, even if the attacker did not obtain +full execution control. + +CC: qemu-stable@nongnu.org +Signed-off-by: Eric Blake +--- + nbd/server.c | 4 ++++ + 1 file changed, 4 insertions(+) + +diff --git a/nbd/server.c b/nbd/server.c +index a81801e3bc..92c0fdd03b 100644 +--- a/nbd/server.c ++++ b/nbd/server.c +@@ -386,6 +386,10 @@ static int nbd_negotiate_handle_info(NBDClient *client, uint32_t length, + msg = "name length is incorrect"; + goto invalid; + } ++ if (namelen >= sizeof(name)) { ++ msg = "name too long for qemu"; ++ goto invalid; ++ } + if (nbd_read(client->ioc, name, namelen, errp) < 0) { + return -EIO; + } +-- +2.15.0 + -- cgit v1.2.3