From baeb5608735b445f2ca0597307afeb9115c8603a6eecfa6bcb9c6c25f375d6c3 Mon Sep 17 00:00:00 2001 From: Bruce Rogers Date: Tue, 17 Mar 2020 13:47:06 +0000 Subject: [PATCH] Accepting request 785936 from home:bfrogers:branches:Virtualization - Fix potential OOB accesses in slirp (CVE-2020-8608 bsc#1163018 bsc#1161066 CVE-2020-7039) slirp-use-correct-size-while-emulating-c.patch slirp-use-correct-size-while-emulating-I.patch tcp_emu-Fix-oob-access.patch tcp_emu-fix-unsafe-snprintf-usages.patch util-add-slirp_fmt-helpers.patch - Replace this patch with upstream version target-arm-monitor-query-cpu-model-expan.patch OBS-URL: https://build.opensuse.org/request/show/785936 OBS-URL: https://build.opensuse.org/package/show/Virtualization/qemu?expand=0&rev=536 --- bundles.tar.xz | 4 +- qemu.changes | 13 ++ qemu.spec | 121 +++++++++------- ...p-use-correct-size-while-emulating-I.patch | 58 ++++++++ ...p-use-correct-size-while-emulating-c.patch | 53 +++++++ ...et-arm-monitor-query-cpu-model-expan.patch | 9 +- tcp_emu-Fix-oob-access.patch | 40 ++++++ tcp_emu-fix-unsafe-snprintf-usages.patch | 134 ++++++++++++++++++ util-add-slirp_fmt-helpers.patch | 125 ++++++++++++++++ 9 files changed, 498 insertions(+), 59 deletions(-) create mode 100644 slirp-use-correct-size-while-emulating-I.patch create mode 100644 slirp-use-correct-size-while-emulating-c.patch create mode 100644 tcp_emu-Fix-oob-access.patch create mode 100644 tcp_emu-fix-unsafe-snprintf-usages.patch create mode 100644 util-add-slirp_fmt-helpers.patch diff --git a/bundles.tar.xz b/bundles.tar.xz index d5c5db4..6d5e61a 100644 --- a/bundles.tar.xz +++ b/bundles.tar.xz @@ -1,3 +1,3 @@ version https://git-lfs.github.com/spec/v1 -oid sha256:e4135bcee5cdc6889a49bd0f162dc9eb258528d48bc9dedd458430e174aa8530 -size 92732 +oid sha256:596a134fe14bb9bca1c177f682098f030ae5741767b562413a0212570aa863e1 +size 95812 diff --git a/qemu.changes b/qemu.changes index a013d82..a972e9f 100644 --- a/qemu.changes +++ b/qemu.changes @@ -1,3 +1,16 @@ +------------------------------------------------------------------- +Mon Mar 16 19:58:35 UTC 2020 - Bruce Rogers + +- Fix potential OOB accesses in slirp (CVE-2020-8608 bsc#1163018 + bsc#1161066 CVE-2020-7039) + slirp-use-correct-size-while-emulating-c.patch + slirp-use-correct-size-while-emulating-I.patch + tcp_emu-Fix-oob-access.patch + tcp_emu-fix-unsafe-snprintf-usages.patch + util-add-slirp_fmt-helpers.patch +- Replace this patch with upstream version + target-arm-monitor-query-cpu-model-expan.patch + ------------------------------------------------------------------- Thu Mar 12 16:27:03 UTC 2020 - Bruce Rogers diff --git a/qemu.spec b/qemu.spec index e850c65..9481aaf 100644 --- a/qemu.spec +++ b/qemu.spec @@ -188,61 +188,61 @@ Patch00057: block-fix-memleaks-in-bdrv_refresh_filen.patch Patch00058: block-backup-top-fix-failure-path.patch Patch00059: iotests-add-test-for-backup-top-failure-.patch Patch00060: audio-oss-fix-buffer-pos-calculation.patch -Patch00061: block-fix-crash-on-zero-length-unaligned.patch -Patch00062: block-Fix-VM-size-field-width-in-snapsho.patch -Patch00063: target-arm-Correct-definition-of-PMCRDP.patch -Patch00064: block-nbd-extract-the-common-cleanup-cod.patch -Patch00065: block-nbd-fix-memory-leak-in-nbd_open.patch -Patch00066: virtio-crypto-do-delete-ctrl_vq-in-virti.patch -Patch00067: virtio-pmem-do-delete-rq_vq-in-virtio_pm.patch -Patch00068: vhost-user-blk-delete-virtioqueues-in-un.patch -Patch00069: hw-arm-cubieboard-use-ARM-Cortex-A8-as-t.patch -Patch00070: iotests-Fix-nonportable-use-of-od-endian.patch -Patch00071: block-qcow2-threads-fix-qcow2_decompress.patch -Patch00072: job-refactor-progress-to-separate-object.patch -Patch00073: block-block-copy-fix-progress-calculatio.patch -Patch00074: XXX-dont-dump-core-on-sigabort.patch -Patch00075: qemu-binfmt-conf-Modify-default-path.patch -Patch00076: qemu-cvs-gettimeofday.patch -Patch00077: qemu-cvs-ioctl_debug.patch -Patch00078: qemu-cvs-ioctl_nodirection.patch -Patch00079: linux-user-add-binfmt-wrapper-for-argv-0.patch -Patch00080: PPC-KVM-Disable-mmu-notifier-check.patch -Patch00081: linux-user-binfmt-support-host-binaries.patch -Patch00082: linux-user-Fake-proc-cpuinfo.patch -Patch00083: linux-user-use-target_ulong.patch -Patch00084: Make-char-muxer-more-robust-wrt-small-FI.patch -Patch00085: linux-user-lseek-explicitly-cast-non-set.patch -Patch00086: AIO-Reduce-number-of-threads-for-32bit-h.patch -Patch00087: xen_disk-Add-suse-specific-flush-disable.patch -Patch00088: qemu-bridge-helper-reduce-security-profi.patch -Patch00089: qemu-binfmt-conf-use-qemu-ARCH-binfmt.patch -Patch00090: linux-user-properly-test-for-infinite-ti.patch -Patch00091: roms-Makefile-pass-a-packaging-timestamp.patch -Patch00092: Raise-soft-address-space-limit-to-hard-l.patch -Patch00093: increase-x86_64-physical-bits-to-42.patch -Patch00094: vga-Raise-VRAM-to-16-MiB-for-pc-0.15-and.patch -Patch00095: i8254-Fix-migration-from-SLE11-SP2.patch -Patch00096: acpi_piix4-Fix-migration-from-SLE11-SP2.patch -Patch00097: Switch-order-of-libraries-for-mpath-supp.patch -Patch00098: Make-installed-scripts-explicitly-python.patch -Patch00099: hw-smbios-handle-both-file-formats-regar.patch -Patch00100: xen-add-block-resize-support-for-xen-dis.patch -Patch00101: tests-qemu-iotests-Triple-timeout-of-i-o.patch -Patch00102: tests-Fix-block-tests-to-be-compatible-w.patch -Patch00103: xen-ignore-live-parameter-from-xen-save-.patch -Patch00104: Conditionalize-ui-bitmap-installation-be.patch -Patch00105: tests-change-error-message-in-test-162.patch -Patch00106: hw-usb-hcd-xhci-Fix-GCC-9-build-warning.patch -Patch00107: hw-usb-dev-mtp-Fix-GCC-9-build-warning.patch -Patch00108: hw-intc-exynos4210_gic-provide-more-room.patch -Patch00109: configure-only-populate-roms-if-softmmu.patch -Patch00110: pc-bios-s390-ccw-net-avoid-warning-about.patch -Patch00111: roms-change-cross-compiler-naming-to-be-.patch -Patch00112: tests-Disable-some-block-tests-for-now.patch -Patch00113: test-add-mapping-from-arch-of-i686-to-qe.patch -Patch00114: roms-Makefile-enable-cross-compile-for-b.patch -Patch00115: target-arm-monitor-query-cpu-model-expan.patch +Patch00061: target-arm-monitor-query-cpu-model-expan.patch +Patch00062: block-fix-crash-on-zero-length-unaligned.patch +Patch00063: block-Fix-VM-size-field-width-in-snapsho.patch +Patch00064: target-arm-Correct-definition-of-PMCRDP.patch +Patch00065: block-nbd-extract-the-common-cleanup-cod.patch +Patch00066: block-nbd-fix-memory-leak-in-nbd_open.patch +Patch00067: virtio-crypto-do-delete-ctrl_vq-in-virti.patch +Patch00068: virtio-pmem-do-delete-rq_vq-in-virtio_pm.patch +Patch00069: vhost-user-blk-delete-virtioqueues-in-un.patch +Patch00070: hw-arm-cubieboard-use-ARM-Cortex-A8-as-t.patch +Patch00071: iotests-Fix-nonportable-use-of-od-endian.patch +Patch00072: block-qcow2-threads-fix-qcow2_decompress.patch +Patch00073: job-refactor-progress-to-separate-object.patch +Patch00074: block-block-copy-fix-progress-calculatio.patch +Patch00075: XXX-dont-dump-core-on-sigabort.patch +Patch00076: qemu-binfmt-conf-Modify-default-path.patch +Patch00077: qemu-cvs-gettimeofday.patch +Patch00078: qemu-cvs-ioctl_debug.patch +Patch00079: qemu-cvs-ioctl_nodirection.patch +Patch00080: linux-user-add-binfmt-wrapper-for-argv-0.patch +Patch00081: PPC-KVM-Disable-mmu-notifier-check.patch +Patch00082: linux-user-binfmt-support-host-binaries.patch +Patch00083: linux-user-Fake-proc-cpuinfo.patch +Patch00084: linux-user-use-target_ulong.patch +Patch00085: Make-char-muxer-more-robust-wrt-small-FI.patch +Patch00086: linux-user-lseek-explicitly-cast-non-set.patch +Patch00087: AIO-Reduce-number-of-threads-for-32bit-h.patch +Patch00088: xen_disk-Add-suse-specific-flush-disable.patch +Patch00089: qemu-bridge-helper-reduce-security-profi.patch +Patch00090: qemu-binfmt-conf-use-qemu-ARCH-binfmt.patch +Patch00091: linux-user-properly-test-for-infinite-ti.patch +Patch00092: roms-Makefile-pass-a-packaging-timestamp.patch +Patch00093: Raise-soft-address-space-limit-to-hard-l.patch +Patch00094: increase-x86_64-physical-bits-to-42.patch +Patch00095: vga-Raise-VRAM-to-16-MiB-for-pc-0.15-and.patch +Patch00096: i8254-Fix-migration-from-SLE11-SP2.patch +Patch00097: acpi_piix4-Fix-migration-from-SLE11-SP2.patch +Patch00098: Switch-order-of-libraries-for-mpath-supp.patch +Patch00099: Make-installed-scripts-explicitly-python.patch +Patch00100: hw-smbios-handle-both-file-formats-regar.patch +Patch00101: xen-add-block-resize-support-for-xen-dis.patch +Patch00102: tests-qemu-iotests-Triple-timeout-of-i-o.patch +Patch00103: tests-Fix-block-tests-to-be-compatible-w.patch +Patch00104: xen-ignore-live-parameter-from-xen-save-.patch +Patch00105: Conditionalize-ui-bitmap-installation-be.patch +Patch00106: tests-change-error-message-in-test-162.patch +Patch00107: hw-usb-hcd-xhci-Fix-GCC-9-build-warning.patch +Patch00108: hw-usb-dev-mtp-Fix-GCC-9-build-warning.patch +Patch00109: hw-intc-exynos4210_gic-provide-more-room.patch +Patch00110: configure-only-populate-roms-if-softmmu.patch +Patch00111: pc-bios-s390-ccw-net-avoid-warning-about.patch +Patch00112: roms-change-cross-compiler-naming-to-be-.patch +Patch00113: tests-Disable-some-block-tests-for-now.patch +Patch00114: test-add-mapping-from-arch-of-i686-to-qe.patch +Patch00115: roms-Makefile-enable-cross-compile-for-b.patch Patch00116: hw-i386-disable-smbus-migration-for-xenf.patch # Patches applied in roms/seabios/: Patch01000: seabios-use-python2-explicitly-as-needed.patch @@ -259,6 +259,12 @@ Patch03000: sgabios-Makefile-fix-issues-of-build-rep.patch Patch03001: roms-sgabios-Fix-csum8-to-be-built-by-ho.patch # Patches applied in ui/keycodemapdb/: Patch08000: Make-keycode-gen-output-reproducible-use.patch +# Patches applied in slirp/: +Patch09000: util-add-slirp_fmt-helpers.patch +Patch09001: slirp-use-correct-size-while-emulating-I.patch +Patch09002: tcp_emu-Fix-oob-access.patch +Patch09003: slirp-use-correct-size-while-emulating-c.patch +Patch09004: tcp_emu-fix-unsafe-snprintf-usages.patch # Patches applied in roms/qboot/: Patch12000: ensure-headers-included-are-compatible-w.patch Patch12001: Enable-cross-compile-prefix-for-C-compil.patch @@ -1085,6 +1091,11 @@ This package provides a service file for starting and stopping KSM. %patch03000 -p1 %patch03001 -p1 %patch08000 -p1 +%patch09000 -p1 +%patch09001 -p1 +%patch09002 -p1 +%patch09003 -p1 +%patch09004 -p1 %patch12000 -p1 %patch12001 -p1 diff --git a/slirp-use-correct-size-while-emulating-I.patch b/slirp-use-correct-size-while-emulating-I.patch new file mode 100644 index 0000000..60c4533 --- /dev/null +++ b/slirp-use-correct-size-while-emulating-I.patch @@ -0,0 +1,58 @@ +From: Prasad J Pandit +Date: Thu, 9 Jan 2020 15:12:27 +0530 +Subject: slirp: use correct size while emulating IRC commands + +Git-commit: ce131029d6d4a405cb7d3ac6716d03e58fb4a5d9 +References: bsc#1163018, CVE-2020-8608 + +While emulating IRC DCC commands, tcp_emu() uses 'mbuf' size +'m->m_size' to write DCC commands via snprintf(3). This may +lead to OOB write access, because 'bptr' points somewhere in +the middle of 'mbuf' buffer, not at the start. Use M_FREEROOM(m) +size to avoid OOB access. + +Reported-by: Vishnu Dev TJ +Signed-off-by: Prasad J Pandit +Reviewed-by: Samuel Thibault +Message-Id: <20200109094228.79764-2-ppandit@redhat.com> +Signed-off-by: Bruce Rogers +--- + src/tcp_subr.c | 11 ++++++----- + 1 file changed, 6 insertions(+), 5 deletions(-) + +diff --git a/slirp/src/tcp_subr.c b/slirp/src/tcp_subr.c +index d6dd133a9f7082dbc6fafdfa7e01..6cd181c9f2875528adab3f636aec 100644 +--- a/slirp/src/tcp_subr.c ++++ b/slirp/src/tcp_subr.c +@@ -778,7 +778,8 @@ int tcp_emu(struct socket *so, struct mbuf *m) + return 1; + } + m->m_len = bptr - m->m_data; /* Adjust length */ +- m->m_len += snprintf(bptr, m->m_size, "DCC CHAT chat %lu %u%c\n", ++ m->m_len += snprintf(bptr, M_FREEROOM(m), ++ "DCC CHAT chat %lu %u%c\n", + (unsigned long)ntohl(so->so_faddr.s_addr), + ntohs(so->so_fport), 1); + } else if (sscanf(bptr, "DCC SEND %256s %u %u %u", buff, &laddr, &lport, +@@ -788,8 +789,8 @@ int tcp_emu(struct socket *so, struct mbuf *m) + return 1; + } + m->m_len = bptr - m->m_data; /* Adjust length */ +- m->m_len += +- snprintf(bptr, m->m_size, "DCC SEND %s %lu %u %u%c\n", buff, ++ m->m_len += snprintf(bptr, M_FREEROOM(m), ++ "DCC SEND %s %lu %u %u%c\n", buff, + (unsigned long)ntohl(so->so_faddr.s_addr), + ntohs(so->so_fport), n1, 1); + } else if (sscanf(bptr, "DCC MOVE %256s %u %u %u", buff, &laddr, &lport, +@@ -799,8 +800,8 @@ int tcp_emu(struct socket *so, struct mbuf *m) + return 1; + } + m->m_len = bptr - m->m_data; /* Adjust length */ +- m->m_len += +- snprintf(bptr, m->m_size, "DCC MOVE %s %lu %u %u%c\n", buff, ++ m->m_len += snprintf(bptr, M_FREEROOM(m), ++ "DCC MOVE %s %lu %u %u%c\n", buff, + (unsigned long)ntohl(so->so_faddr.s_addr), + ntohs(so->so_fport), n1, 1); + } diff --git a/slirp-use-correct-size-while-emulating-c.patch b/slirp-use-correct-size-while-emulating-c.patch new file mode 100644 index 0000000..d71385b --- /dev/null +++ b/slirp-use-correct-size-while-emulating-c.patch @@ -0,0 +1,53 @@ +From: Prasad J Pandit +Date: Thu, 9 Jan 2020 15:12:28 +0530 +Subject: slirp: use correct size while emulating commands + +Git-commit: 82ebe9c370a0e2970fb5695aa19aa5214a6a1c80 +References: bsc#1161066, CVE2020-7039, bsc#1163018, CVE-2020-8608 + +While emulating services in tcp_emu(), it uses 'mbuf' size +'m->m_size' to write commands via snprintf(3). Use M_FREEROOM(m) +size to avoid possible OOB access. + +Signed-off-by: Prasad J Pandit +Signed-off-by: Samuel Thibault +Message-Id: <20200109094228.79764-3-ppandit@redhat.com> +Signed-off-by: Bruce Rogers +--- + src/tcp_subr.c | 9 ++++----- + 1 file changed, 4 insertions(+), 5 deletions(-) + +diff --git a/slirp/src/tcp_subr.c b/slirp/src/tcp_subr.c +index cedbfb28686604dbb7e8e5b35dd1..954d1a6f5e6292b585638a8c0558 100644 +--- a/slirp/src/tcp_subr.c ++++ b/slirp/src/tcp_subr.c +@@ -696,7 +696,7 @@ int tcp_emu(struct socket *so, struct mbuf *m) + n4 = (laddr & 0xff); + + m->m_len = bptr - m->m_data; /* Adjust length */ +- m->m_len += snprintf(bptr, m->m_size - m->m_len, ++ m->m_len += snprintf(bptr, M_FREEROOM(m), + "ORT %d,%d,%d,%d,%d,%d\r\n%s", n1, n2, n3, n4, + n5, n6, x == 7 ? buff : ""); + return 1; +@@ -731,8 +731,7 @@ int tcp_emu(struct socket *so, struct mbuf *m) + n4 = (laddr & 0xff); + + m->m_len = bptr - m->m_data; /* Adjust length */ +- m->m_len += +- snprintf(bptr, m->m_size - m->m_len, ++ m->m_len += snprintf(bptr, M_FREEROOM(m), + "27 Entering Passive Mode (%d,%d,%d,%d,%d,%d)\r\n%s", + n1, n2, n3, n4, n5, n6, x == 7 ? buff : ""); + +@@ -758,8 +757,8 @@ int tcp_emu(struct socket *so, struct mbuf *m) + if (m->m_data[m->m_len - 1] == '\0' && lport != 0 && + (so = tcp_listen(slirp, INADDR_ANY, 0, so->so_laddr.s_addr, + htons(lport), SS_FACCEPTONCE)) != NULL) +- m->m_len = +- snprintf(m->m_data, m->m_size, "%d", ntohs(so->so_fport)) + 1; ++ m->m_len = snprintf(m->m_data, M_ROOM(m), ++ "%d", ntohs(so->so_fport)) + 1; + return 1; + + case EMU_IRC: diff --git a/target-arm-monitor-query-cpu-model-expan.patch b/target-arm-monitor-query-cpu-model-expan.patch index bf28dbf..b2db4b5 100644 --- a/target-arm-monitor-query-cpu-model-expan.patch +++ b/target-arm-monitor-query-cpu-model-expan.patch @@ -1,8 +1,9 @@ From: Liang Yan -Date: Fri, 31 Jan 2020 14:54:06 -0500 +Date: Fri, 7 Feb 2020 14:04:21 +0000 Subject: target/arm/monitor: query-cpu-model-expansion crashed qemu when using machine type none +Git-commit: 0999a4ba8718aa96105b978d3567fc7e90244c7e References: bsc#1159443 Commit e19afd566781 mentioned that target-arm only supports queryable @@ -15,8 +16,12 @@ So We add a check above it. This won't affect i386 and s390x since they do not use current_cpu. -[LY: patch only queued in upstream, will update commit id later] Signed-off-by: Liang Yan +Message-id: 20200203134251.12986-1-lyan@suse.com +Reviewed-by: Andrew Jones +Tested-by: Andrew Jones +Signed-off-by: Peter Maydell +Signed-off-by: Bruce Rogers --- target/arm/monitor.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/tcp_emu-Fix-oob-access.patch b/tcp_emu-Fix-oob-access.patch new file mode 100644 index 0000000..2e3b9a6 --- /dev/null +++ b/tcp_emu-Fix-oob-access.patch @@ -0,0 +1,40 @@ +From: Samuel Thibault +Date: Wed, 8 Jan 2020 00:58:48 +0100 +Subject: tcp_emu: Fix oob access + +Git-commit: 2655fffed7a9e765bcb4701dd876e9dab975f289 +References: bsc#1161066, CVE2020-7039, bsc#1161066, CVS-2020-7039 + +The main loop only checks for one available byte, while we sometimes +need two bytes. + +Signed-off-by: Bruce Rogers +--- + src/tcp_subr.c | 7 +++++++ + 1 file changed, 7 insertions(+) + +diff --git a/slirp/src/tcp_subr.c b/slirp/src/tcp_subr.c +index 6cd181c9f2875528adab3f636aec..cedbfb28686604dbb7e8e5b35dd1 100644 +--- a/slirp/src/tcp_subr.c ++++ b/slirp/src/tcp_subr.c +@@ -887,6 +887,9 @@ int tcp_emu(struct socket *so, struct mbuf *m) + break; + + case 5: ++ if (bptr == m->m_data + m->m_len - 1) ++ return 1; /* We need two bytes */ ++ + /* + * The difference between versions 1.0 and + * 2.0 is here. For future versions of +@@ -902,6 +905,10 @@ int tcp_emu(struct socket *so, struct mbuf *m) + /* This is the field containing the port + * number that RA-player is listening to. + */ ++ ++ if (bptr == m->m_data + m->m_len - 1) ++ return 1; /* We need two bytes */ ++ + lport = (((uint8_t *)bptr)[0] << 8) + ((uint8_t *)bptr)[1]; + if (lport < 6970) + lport += 256; /* don't know why */ diff --git a/tcp_emu-fix-unsafe-snprintf-usages.patch b/tcp_emu-fix-unsafe-snprintf-usages.patch new file mode 100644 index 0000000..2292f03 --- /dev/null +++ b/tcp_emu-fix-unsafe-snprintf-usages.patch @@ -0,0 +1,134 @@ +From: =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= +Date: Mon, 27 Jan 2020 10:24:14 +0100 +Subject: tcp_emu: fix unsafe snprintf() usages +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +Git-commit: 68ccb8021a838066f0951d4b2817eb6b6f10a843 +References: bsc#1163018, CVE-2020-8608 + +Various calls to snprintf() assume that snprintf() returns "only" the +number of bytes written (excluding terminating NUL). + +https://pubs.opengroup.org/onlinepubs/9699919799/functions/snprintf.html#tag_16_159_04 + +"Upon successful completion, the snprintf() function shall return the +number of bytes that would be written to s had n been sufficiently +large excluding the terminating null byte." + +Before patch ce131029, if there isn't enough room in "m_data" for the +"DCC ..." message, we overflow "m_data". + +After the patch, if there isn't enough room for the same, we don't +overflow "m_data", but we set "m_len" out-of-bounds. The next time an +access is bounded by "m_len", we'll have a buffer overflow then. + +Use slirp_fmt*() to fix potential OOB memory access. + +Reported-by: Laszlo Ersek +Signed-off-by: Marc-André Lureau +Reviewed-by: Samuel Thibault +Message-Id: <20200127092414.169796-7-marcandre.lureau@redhat.com> +Signed-off-by: Bruce Rogers +--- + src/tcp_subr.c | 44 +++++++++++++++++++++----------------------- + 1 file changed, 21 insertions(+), 23 deletions(-) + +diff --git a/slirp/src/tcp_subr.c b/slirp/src/tcp_subr.c +index 954d1a6f5e6292b585638a8c0558..26d4ead543a5357577817b39a3d6 100644 +--- a/slirp/src/tcp_subr.c ++++ b/slirp/src/tcp_subr.c +@@ -655,8 +655,7 @@ int tcp_emu(struct socket *so, struct mbuf *m) + NTOHS(n1); + NTOHS(n2); + m_inc(m, snprintf(NULL, 0, "%d,%d\r\n", n1, n2) + 1); +- m->m_len = snprintf(m->m_data, M_ROOM(m), "%d,%d\r\n", n1, n2); +- assert(m->m_len < M_ROOM(m)); ++ m->m_len = slirp_fmt(m->m_data, M_ROOM(m), "%d,%d\r\n", n1, n2); + } else { + *eol = '\r'; + } +@@ -696,9 +695,9 @@ int tcp_emu(struct socket *so, struct mbuf *m) + n4 = (laddr & 0xff); + + m->m_len = bptr - m->m_data; /* Adjust length */ +- m->m_len += snprintf(bptr, M_FREEROOM(m), +- "ORT %d,%d,%d,%d,%d,%d\r\n%s", n1, n2, n3, n4, +- n5, n6, x == 7 ? buff : ""); ++ m->m_len += slirp_fmt(bptr, M_FREEROOM(m), ++ "ORT %d,%d,%d,%d,%d,%d\r\n%s", ++ n1, n2, n3, n4, n5, n6, x == 7 ? buff : ""); + return 1; + } else if ((bptr = (char *)strstr(m->m_data, "27 Entering")) != NULL) { + /* +@@ -731,10 +730,9 @@ int tcp_emu(struct socket *so, struct mbuf *m) + n4 = (laddr & 0xff); + + m->m_len = bptr - m->m_data; /* Adjust length */ +- m->m_len += snprintf(bptr, M_FREEROOM(m), +- "27 Entering Passive Mode (%d,%d,%d,%d,%d,%d)\r\n%s", +- n1, n2, n3, n4, n5, n6, x == 7 ? buff : ""); +- ++ m->m_len += slirp_fmt(bptr, M_FREEROOM(m), ++ "27 Entering Passive Mode (%d,%d,%d,%d,%d,%d)\r\n%s", ++ n1, n2, n3, n4, n5, n6, x == 7 ? buff : ""); + return 1; + } + +@@ -757,8 +755,8 @@ int tcp_emu(struct socket *so, struct mbuf *m) + if (m->m_data[m->m_len - 1] == '\0' && lport != 0 && + (so = tcp_listen(slirp, INADDR_ANY, 0, so->so_laddr.s_addr, + htons(lport), SS_FACCEPTONCE)) != NULL) +- m->m_len = snprintf(m->m_data, M_ROOM(m), +- "%d", ntohs(so->so_fport)) + 1; ++ m->m_len = slirp_fmt0(m->m_data, M_ROOM(m), ++ "%d", ntohs(so->so_fport)); + return 1; + + case EMU_IRC: +@@ -777,10 +775,10 @@ int tcp_emu(struct socket *so, struct mbuf *m) + return 1; + } + m->m_len = bptr - m->m_data; /* Adjust length */ +- m->m_len += snprintf(bptr, M_FREEROOM(m), +- "DCC CHAT chat %lu %u%c\n", +- (unsigned long)ntohl(so->so_faddr.s_addr), +- ntohs(so->so_fport), 1); ++ m->m_len += slirp_fmt(bptr, M_FREEROOM(m), ++ "DCC CHAT chat %lu %u%c\n", ++ (unsigned long)ntohl(so->so_faddr.s_addr), ++ ntohs(so->so_fport), 1); + } else if (sscanf(bptr, "DCC SEND %256s %u %u %u", buff, &laddr, &lport, + &n1) == 4) { + if ((so = tcp_listen(slirp, INADDR_ANY, 0, htonl(laddr), +@@ -788,10 +786,10 @@ int tcp_emu(struct socket *so, struct mbuf *m) + return 1; + } + m->m_len = bptr - m->m_data; /* Adjust length */ +- m->m_len += snprintf(bptr, M_FREEROOM(m), +- "DCC SEND %s %lu %u %u%c\n", buff, +- (unsigned long)ntohl(so->so_faddr.s_addr), +- ntohs(so->so_fport), n1, 1); ++ m->m_len += slirp_fmt(bptr, M_FREEROOM(m), ++ "DCC SEND %s %lu %u %u%c\n", buff, ++ (unsigned long)ntohl(so->so_faddr.s_addr), ++ ntohs(so->so_fport), n1, 1); + } else if (sscanf(bptr, "DCC MOVE %256s %u %u %u", buff, &laddr, &lport, + &n1) == 4) { + if ((so = tcp_listen(slirp, INADDR_ANY, 0, htonl(laddr), +@@ -799,10 +797,10 @@ int tcp_emu(struct socket *so, struct mbuf *m) + return 1; + } + m->m_len = bptr - m->m_data; /* Adjust length */ +- m->m_len += snprintf(bptr, M_FREEROOM(m), +- "DCC MOVE %s %lu %u %u%c\n", buff, +- (unsigned long)ntohl(so->so_faddr.s_addr), +- ntohs(so->so_fport), n1, 1); ++ m->m_len += slirp_fmt(bptr, M_FREEROOM(m), ++ "DCC MOVE %s %lu %u %u%c\n", buff, ++ (unsigned long)ntohl(so->so_faddr.s_addr), ++ ntohs(so->so_fport), n1, 1); + } + return 1; + diff --git a/util-add-slirp_fmt-helpers.patch b/util-add-slirp_fmt-helpers.patch new file mode 100644 index 0000000..8da70b1 --- /dev/null +++ b/util-add-slirp_fmt-helpers.patch @@ -0,0 +1,125 @@ +From: =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= +Date: Mon, 27 Jan 2020 10:24:09 +0100 +Subject: util: add slirp_fmt() helpers +MIME-Version: 1.0 +Content-Type: text/plain; charset=UTF-8 +Content-Transfer-Encoding: 8bit + +Git-commit: 30648c03b27fb8d9611b723184216cd3174b6775 +References: bsc#1163018, CVE-2020-8608 + +Various calls to snprintf() in libslirp assume that snprintf() returns +"only" the number of bytes written (excluding terminating NUL). + +https://pubs.opengroup.org/onlinepubs/9699919799/functions/snprintf.html#tag_16_159_04 + +"Upon successful completion, the snprintf() function shall return the +number of bytes that would be written to s had n been sufficiently +large excluding the terminating null byte." + +Introduce slirp_fmt() that handles several pathological cases the +way libslirp usually expect: + +- treat error as fatal (instead of silently returning -1) + +- fmt0() will always \0 end + +- return the number of bytes actually written (instead of what would +have been written, which would usually result in OOB later), including +the ending \0 for fmt0() + +- warn if truncation happened (instead of ignoring) + +Other less common cases can still be handled with strcpy/snprintf() etc. + +Signed-off-by: Marc-André Lureau +Reviewed-by: Samuel Thibault +Message-Id: <20200127092414.169796-2-marcandre.lureau@redhat.com> +Signed-off-by: Bruce Rogers +--- + src/util.c | 62 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ + src/util.h | 3 +++ + 2 files changed, 65 insertions(+) + +diff --git a/slirp/src/util.c b/slirp/src/util.c +index e5960871554e37ab67a640d2cd9b..e3b625717b0f5ef6e54756045a17 100644 +--- a/slirp/src/util.c ++++ b/slirp/src/util.c +@@ -364,3 +364,65 @@ void slirp_pstrcpy(char *buf, int buf_size, const char *str) + } + *q = '\0'; + } ++ ++static int slirp_vsnprintf(char *str, size_t size, ++ const char *format, va_list args) ++{ ++ int rv = vsnprintf(str, size, format, args); ++ ++ if (rv < 0) { ++ g_error("vsnprintf() failed: %s", g_strerror(errno)); ++ } ++ ++ return rv; ++} ++ ++/* ++ * A snprintf()-like function that: ++ * - returns the number of bytes written (excluding optional \0-ending) ++ * - dies on error ++ * - warn on truncation ++ */ ++int slirp_fmt(char *str, size_t size, const char *format, ...) ++{ ++ va_list args; ++ int rv; ++ ++ va_start(args, format); ++ rv = slirp_vsnprintf(str, size, format, args); ++ va_end(args); ++ ++ if (rv > size) { ++ g_critical("vsnprintf() truncation"); ++ } ++ ++ return MIN(rv, size); ++} ++ ++/* ++ * A snprintf()-like function that: ++ * - always \0-end (unless size == 0) ++ * - returns the number of bytes actually written, including \0 ending ++ * - dies on error ++ * - warn on truncation ++ */ ++int slirp_fmt0(char *str, size_t size, const char *format, ...) ++{ ++ va_list args; ++ int rv; ++ ++ va_start(args, format); ++ rv = slirp_vsnprintf(str, size, format, args); ++ va_end(args); ++ ++ if (rv >= size) { ++ g_critical("vsnprintf() truncation"); ++ if (size > 0) ++ str[size - 1] = '\0'; ++ rv = size; ++ } else { ++ rv += 1; /* include \0 */ ++ } ++ ++ return rv; ++} +diff --git a/slirp/src/util.h b/slirp/src/util.h +index 3c6223cecd9d881ca1a3f2d37af2..0558dfc222ec7d7b43beb2d18161 100644 +--- a/slirp/src/util.h ++++ b/slirp/src/util.h +@@ -177,4 +177,7 @@ static inline int slirp_socket_set_fast_reuse(int fd) + + void slirp_pstrcpy(char *buf, int buf_size, const char *str); + ++int slirp_fmt(char *str, size_t size, const char *format, ...); ++int slirp_fmt0(char *str, size_t size, const char *format, ...); ++ + #endif