[OE-core] [PATCH] procps:Fix CVE-2018-1122&CVE-2018-1123
akuster808
akuster808 at gmail.com
Tue Jun 26 14:49:03 UTC 2018
On 06/26/2018 12:35 AM, Hong Liu wrote:
> 1.0001-top-Do-not-default-to-the-cwd-in-configs_read.patch fixed CVE-2018-1122
>
> 2.0001-ps-output.c-Fix-outbuf-overflows-in-pr_args-etc.patch fixed CVE-2018-1123
> ---
> ...put.c-Fix-outbuf-overflows-in-pr_args-etc.patch | 84 +++++++++++++++++
> ...Do-not-default-to-the-cwd-in-configs_read.patch | 101 +++++++++++++++++++++
> meta/recipes-extended/procps/procps_3.3.14.bb | 2 +
> 3 files changed, 187 insertions(+)
> create mode 100644 meta/recipes-extended/procps/procps/0001-ps-output.c-Fix-outbuf-overflows-in-pr_args-etc.patch
> create mode 100644 meta/recipes-extended/procps/procps/0001-top-Do-not-default-to-the-cwd-in-configs_read.patch
>
> diff --git a/meta/recipes-extended/procps/procps/0001-ps-output.c-Fix-outbuf-overflows-in-pr_args-etc.patch b/meta/recipes-extended/procps/procps/0001-ps-output.c-Fix-outbuf-overflows-in-pr_args-etc.patch
> new file mode 100644
> index 0000000..ab4fc23
> --- /dev/null
> +++ b/meta/recipes-extended/procps/procps/0001-ps-output.c-Fix-outbuf-overflows-in-pr_args-etc.patch
> @@ -0,0 +1,84 @@
> +From 136e3724952827bbae8887a42d9d2b6f658a48ab Mon Sep 17 00:00:00 2001
> +From: Qualys Security Advisory <qsa at qualys.com>
> +Date: Thu, 1 Jan 1970 00:00:00 +0000
> +Subject: [PATCH] ps/output.c: Fix outbuf overflows in pr_args() etc.
> +
> +Because there is usually less than OUTBUF_SIZE available at endp.
> +
> +Upstream-Status: Backport
Patch missing signed-off-by
> +---
> + ps/output.c | 23 ++++++++++++++---------
> + 1 file changed, 14 insertions(+), 9 deletions(-)
> +
> +diff --git a/ps/output.c b/ps/output.c
> +index 0c63bb6..4456f28 100644
> +--- a/ps/output.c
> ++++ b/ps/output.c
> +@@ -389,6 +389,9 @@ Modifications to the arguments are not shown.
> +
> + // FIXME: some of these may hit the guard page in forest mode
> +
> ++#define OUTBUF_SIZE_AT(endp) \
> ++ (((endp) >= outbuf && (endp) < outbuf + OUTBUF_SIZE) ? (outbuf + OUTBUF_SIZE) - (endp) : 0)
> ++
> + /*
> + * "args", "cmd", "command" are all the same: long unless c
> + * "comm", "ucmd", "ucomm" are all the same: short unless -f
> +@@ -402,15 +405,15 @@ static int pr_args(char *restrict const outbuf, const proc_t *restrict const pp)
> + rightward -= fh;
> +
> + if(pp->cmdline && !bsd_c_option)
> +- endp += escaped_copy(endp, *pp->cmdline, OUTBUF_SIZE, &rightward);
> ++ endp += escaped_copy(endp, *pp->cmdline, OUTBUF_SIZE_AT(endp), &rightward);
> + else
> +- endp += escape_command(endp, pp, OUTBUF_SIZE, &rightward, ESC_DEFUNCT);
> ++ endp += escape_command(endp, pp, OUTBUF_SIZE_AT(endp), &rightward, ESC_DEFUNCT);
> +
> +- if(bsd_e_option && rightward>1) {
> ++ if(bsd_e_option && rightward>1 && OUTBUF_SIZE_AT(endp)>1) {
> + if(pp->environ && *pp->environ) {
> + *endp++ = ' ';
> + rightward--;
> +- endp += escape_strlist(endp, pp->environ, OUTBUF_SIZE, &rightward);
> ++ endp += escape_strlist(endp, pp->environ, OUTBUF_SIZE_AT(endp), &rightward);
> + }
> + }
> + return max_rightward-rightward;
> +@@ -429,15 +432,15 @@ static int pr_comm(char *restrict const outbuf, const proc_t *restrict const pp)
> + rightward -= fh;
> +
> + if(pp->cmdline && unix_f_option)
> +- endp += escaped_copy(endp, *pp->cmdline, OUTBUF_SIZE, &rightward);
> ++ endp += escaped_copy(endp, *pp->cmdline, OUTBUF_SIZE_AT(endp), &rightward);
> + else
> +- endp += escape_command(endp, pp, OUTBUF_SIZE, &rightward, ESC_DEFUNCT);
> ++ endp += escape_command(endp, pp, OUTBUF_SIZE_AT(endp), &rightward, ESC_DEFUNCT);
> +
> +- if(bsd_e_option && rightward>1) {
> ++ if(bsd_e_option && rightward>1 && OUTBUF_SIZE_AT(endp)>1) {
> + if(pp->environ && *pp->environ) {
> + *endp++ = ' ';
> + rightward--;
> +- endp += escape_strlist(endp, pp->environ, OUTBUF_SIZE, &rightward);
> ++ endp += escape_strlist(endp, pp->environ, OUTBUF_SIZE_AT(endp), &rightward);
> + }
> + }
> + return max_rightward-rightward;
> +@@ -469,11 +472,13 @@ static int pr_fname(char *restrict const outbuf, const proc_t *restrict const pp
> + if (rightward>8) /* 8=default, but forest maybe feeds more */
> + rightward = 8;
> +
> +- endp += escape_str(endp, pp->cmd, OUTBUF_SIZE, &rightward);
> ++ endp += escape_str(endp, pp->cmd, OUTBUF_SIZE_AT(endp), &rightward);
> + //return endp - outbuf;
> + return max_rightward-rightward;
> + }
> +
> ++#undef OUTBUF_SIZE_AT
> ++
> + /* elapsed wall clock time, [[dd-]hh:]mm:ss format (not same as "time") */
> + static int pr_etime(char *restrict const outbuf, const proc_t *restrict const pp){
> + unsigned long t;
> +--
> +2.14.3
> +
> diff --git a/meta/recipes-extended/procps/procps/0001-top-Do-not-default-to-the-cwd-in-configs_read.patch b/meta/recipes-extended/procps/procps/0001-top-Do-not-default-to-the-cwd-in-configs_read.patch
> new file mode 100644
> index 0000000..8b1b904
> --- /dev/null
> +++ b/meta/recipes-extended/procps/procps/0001-top-Do-not-default-to-the-cwd-in-configs_read.patch
> @@ -0,0 +1,101 @@
> +From b45c4803dd176f4e3f9d3d47421ddec9bbbe66cd Mon Sep 17 00:00:00 2001
> +From: Qualys Security Advisory <qsa at qualys.com>
> +Date: Thu, 1 Jan 1970 00:00:00 +0000
> +Subject: [PATCH] top: Do not default to the cwd in configs_read().
> +
> +If the HOME environment variable is not set, or not absolute, use the
> +home directory returned by getpwuid(getuid()), if set and absolute
> +(instead of the cwd "."); otherwise, set p_home to NULL.
> +
> +To keep the changes to a minimum, we rely on POSIX, which requires that
> +fopen() fails with ENOENT if the pathname (Rc_name) is an empty string.
> +This integrates well into the existing code, and makes write_rcfile()
> +work without a change.
> +
> +Also, it makes the code in configs_read() easier to follow: only set and
> +use p_home if safe, and only set Rc_name if safe (in all the other cases
> +it is the empty string, and the fopen() calls fail). Plus, check for
> +snprintf() truncation (and if it happens, reset Rc_name to the empty
> +string).
> +
> +Important note: top.1 should probably be updated, since it mentions the
> +fallback to the current working directory.
> +
> +Upstream-Status: Backport
> +---
> + top/top.c | 33 ++++++++++++++++++++++++++++-----
> + 1 file changed, 28 insertions(+), 5 deletions(-)
> +
> +diff --git a/top/top.c b/top/top.c
> +index bc609aa..1b5afee 100644
> +--- a/top/top.c
> ++++ b/top/top.c
> +@@ -3810,6 +3810,20 @@ error Hey, fix the above fscanf 'PFLAGSSIZ' dependency !
> + } // end: config_file
> +
> +
> ++static int snprintf_Rc_name (const char *const format, ...) __attribute__((format(printf,1,2)));
> ++static int snprintf_Rc_name (const char *const format, ...) {
> ++ int len;
> ++ va_list ap;
> ++ va_start(ap, format);
> ++ len = vsnprintf(Rc_name, sizeof(Rc_name), format, ap);
> ++ va_end(ap);
> ++ if (len <= 0 || (size_t)len >= sizeof(Rc_name)) {
> ++ Rc_name[0] = '\0';
> ++ return 0;
> ++ }
> ++ return len;
> ++}
> ++
> + /*
> + * Try reading up to 3 rcfiles
> + * 1. 'SYS_RCRESTRICT' contains two lines consisting of the secure
> +@@ -3842,23 +3856,31 @@ static void configs_read (void) {
> + fclose(fp);
> + }
> +
> ++ Rc_name[0] = '\0'; // "fopen() shall fail if pathname is an empty string."
> + // attempt to use the legacy file first, if we cannot access that file, use
> + // the new XDG basedir locations (XDG_CONFIG_HOME or HOME/.config) instead.
> + p_home = getenv("HOME");
> +- if (!p_home || p_home[0] == '\0')
> +- p_home = ".";
> +- snprintf(Rc_name, sizeof(Rc_name), "%s/.%src", p_home, Myname);
> ++ if (!p_home || p_home[0] != '/') {
> ++ const struct passwd *const pwd = getpwuid(getuid());
> ++ if (!pwd || !(p_home = pwd->pw_dir) || p_home[0] != '/') {
> ++ p_home = NULL;
> ++ }
> ++ }
> ++ if (p_home) {
> ++ snprintf_Rc_name("%s/.%src", p_home, Myname);
> ++ }
> +
> + if (!(fp = fopen(Rc_name, "r"))) {
> + p = getenv("XDG_CONFIG_HOME");
> + // ensure the path we get is absolute, fallback otherwise.
> + if (!p || p[0] != '/') {
> ++ if (!p_home) goto system_default;
> + p = fmtmk("%s/.config", p_home);
> + (void)mkdir(p, 0700);
> + }
> +- snprintf(Rc_name, sizeof(Rc_name), "%s/procps", p);
> ++ if (!snprintf_Rc_name("%s/procps", p)) goto system_default;
> + (void)mkdir(Rc_name, 0700);
> +- snprintf(Rc_name, sizeof(Rc_name), "%s/procps/%src", p, Myname);
> ++ if (!snprintf_Rc_name("%s/procps/%src", p, Myname)) goto system_default;
> + fp = fopen(Rc_name, "r");
> + }
> +
> +@@ -3867,6 +3889,7 @@ static void configs_read (void) {
> + fclose(fp);
> + if (p) goto default_or_error;
> + } else {
> ++system_default:
> + fp = fopen(SYS_RCDEFAULTS, "r");
> + if (fp) {
> + p = config_file(fp, SYS_RCDEFAULTS, &tmp_delay);
> +--
> +2.14.3
> +
> diff --git a/meta/recipes-extended/procps/procps_3.3.14.bb b/meta/recipes-extended/procps/procps_3.3.14.bb
> index 1aba511..b7b6b6b 100644
> --- a/meta/recipes-extended/procps/procps_3.3.14.bb
> +++ b/meta/recipes-extended/procps/procps_3.3.14.bb
> @@ -15,6 +15,8 @@ inherit autotools gettext pkgconfig update-alternatives
> SRC_URI = "http://downloads.sourceforge.net/project/procps-ng/Production/procps-ng-${PV}.tar.xz \
> file://sysctl.conf \
> file://0001-Fix-out-of-tree-builds.patch \
> + file://0001-top-Do-not-default-to-the-cwd-in-configs_read.patch \
> + file://0001-ps-output.c-Fix-outbuf-overflows-in-pr_args-etc.patch \
> "
>
> SRC_URI[md5sum] = "fce371ccc1c15a67af9d85e4057e559d"
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