systemd: CVE-2016-7795
cover systemd: CVE-2016-7795
The following changes since commit 6e96deb024e4c41d911f590ff2b92b402f672661:
local.conf.sample.extended: remove RM_OLD_IMAGE (2016-10-19 17:07:14 +0100)
are available in the git repository at:
git://git.openembedded.org/openembedded-core-contrib ChenQi/CVE-2016-7795
http://cgit.openembedded.org/cgit.cgi/openembedded-core-contrib/log/?h=ChenQi/CVE-2016-7795
Chen Qi (1):
systemd: CVE-2016-7795
...s-zero-length-notification-messages-again.patch | 68 ++++++++++++++++++++++ meta/recipes-core/systemd/systemd_230.bb | 1 + 2 files changed, 69 insertions(+) create mode 100644 meta/recipes-core/systemd/systemd/0001-pid1-process-zero-length-notification-messages-again.patch
Signature · 1 line
1.9.1
PATCH 1/1 systemd: CVE-2016-7795
The manager_invoke_notify_message function in systemd 231 and earlier allows local users to cause a denial of service (assertion failure and PID 1 hang) via a zero-length message received over a notify socket.
The patch is a backport from the latest git repo.
Please see the link below for more information.
https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2016-7795
--- ...s-zero-length-notification-messages-again.patch | 68 ++++++++++++++++++++++ meta/recipes-core/systemd/systemd_230.bb | 1 + 2 files changed, 69 insertions(+) create mode 100644 meta/recipes-core/systemd/systemd/0001-pid1-process-zero-length-notification-messages-again.patch
meta/recipes-core/systemd/systemd/0001-pid1-process-zero-length-notification-messages-again.patch new file +68 -0
@@ -0,0 +1,68 @@ +Subject: pid1: process zero-length notification messages again + +This undoes 531ac2b. I acked that patch without looking at the code +carefully enough. There are two problems: +- we want to process the fds anyway +- in principle empty notification messages are valid, and we should + process them as usual, including logging using log_unit_debug(). + +Upstream-Status: Backport + +Signed-off-by: Chen Qi <[email protected]> +--- + src/core/manager.c | 11 ++++++----- + 1 file changed, 6 insertions(+), 5 deletions(-) + +diff --git a/src/core/manager.c b/src/core/manager.c +index 7838f56..f165d08e 100644 +--- a/src/core/manager.c ++++ b/src/core/manager.c +@@ -1589,13 +1589,12 @@ static int manager_dispatch_cgroups_agent_fd(sd_event_source *source, int fd, ui + return 0; + } + +-static void manager_invoke_notify_message(Manager *m, Unit *u, pid_t pid, const char *buf, size_t n, FDSet *fds) { ++static void manager_invoke_notify_message(Manager *m, Unit *u, pid_t pid, const char *buf, FDSet *fds) { + _cleanup_strv_free_ char **tags = NULL; + + assert(m); + assert(u); + assert(buf); +- assert(n > 0); + + tags = strv_split(buf, "\n\r"); + if (!tags) { +@@ -1688,25 +1687,27 @@ static int manager_dispatch_notify_fd(sd_event_source *source, int fd, uint32_t + return 0; + } + ++ /* The message should be a string. Here we make sure it's NUL-terminated, ++ * but only the part until first NUL will be used anyway. */ + buf[n] = 0; + + /* Notify every unit that might be interested, but try + * to avoid notifying the same one multiple times. */ + u1 = manager_get_unit_by_pid_cgroup(m, ucred->pid); + if (u1) { +- manager_invoke_notify_message(m, u1, ucred->pid, buf, n, fds); ++ manager_invoke_notify_message(m, u1, ucred->pid, buf, fds); + found = true; + } + + u2 = hashmap_get(m->watch_pids1, PID_TO_PTR(ucred->pid)); + if (u2 && u2 != u1) { +- manager_invoke_notify_message(m, u2, ucred->pid, buf, n, fds); ++ manager_invoke_notify_message(m, u2, ucred->pid, buf, fds); + found = true; + } + + u3 = hashmap_get(m->watch_pids2, PID_TO_PTR(ucred->pid)); + if (u3 && u3 != u2 && u3 != u1) { +- manager_invoke_notify_message(m, u3, ucred->pid, buf, n, fds); ++ manager_invoke_notify_message(m, u3, ucred->pid, buf, fds); + found = true; + } + +-- +2.8.3 +
meta/recipes-core/systemd/systemd_230.bb +1 -0
@@ -36,6 +36,7 @@ SRC_URI += " \ file://0021-include-missing.h-for-getting-secure_getenv-definiti.patch \ file://0022-socket-util-don-t-fail-if-libc-doesn-t-support-IDN.patch \ file://udev-re-enable-mount-propagation-for-udevd.patch \ + file://0001-pid1-process-zero-length-notification-messages-again.patch \ " SRC_URI_append_libc-uclibc = "\ file://0002-units-Prefer-getty-to-agetty-in-console-setup-system.patch \
Signature · 1 line
1.9.1
Hi All,
I just realized that my patch does not conform to the CVE patch requirement in the link below. I'll send out V2.
http://openembedded.org/wiki/Commit_Patch_Message_Guidelines#Example:_CVE_patch_header
Best Regards,
Chen Qi
Quoted 17 lines · Chen Qi
The following changes since commit
6e96deb024e4c41d911f590ff2b92b402f672661:local.conf.sample.extended: remove RM_OLD_IMAGE (2016-10-19 17:07:14 +0100)are available in the git repository at:
git://git.openembedded.org/openembedded-core-contrib ChenQi/CVE-2016-7795 http://cgit.openembedded.org/cgit.cgi/openembedded-core-contrib/log/?h=ChenQi/CVE-2016-7795Chen Qi (1):
systemd: CVE-2016-7795...s-zero-length-notification-messages-again.patch | 68 ++++++++++++++++++++++ meta/recipes-core/systemd/systemd_230.bb | 1 + 2 files changed, 69 insertions(+)create mode 100644
meta/recipes-core/systemd/systemd/0001-pid1-process-zero-length-notification-messages-again.patch