diff options
| -rw-r--r-- | meta/recipes-extended/procps/procps/CVE-2018-1124.patch | 176 | ||||
| -rw-r--r-- | meta/recipes-extended/procps/procps_3.3.12.bb | 1 |
2 files changed, 177 insertions, 0 deletions
diff --git a/meta/recipes-extended/procps/procps/CVE-2018-1124.patch b/meta/recipes-extended/procps/procps/CVE-2018-1124.patch new file mode 100644 index 0000000000..bc78faf0dc --- /dev/null +++ b/meta/recipes-extended/procps/procps/CVE-2018-1124.patch @@ -0,0 +1,176 @@ +From bdd058a0e676d2f013027fcfb2b344c313112a50 Mon Sep 17 00:00:00 2001 +From: Qualys Security Advisory <qsa@qualys.com> +Date: Thu, 1 Jan 1970 00:00:00 +0000 +Subject: [PATCH 074/126] proc/readproc.c: Fix bugs and overflows in + file2strvec(). + +Note: this is by far the most important and complex patch of the whole +series, please review it carefully; thank you very much! + +For this patch, we decided to keep the original function's design and +skeleton, to avoid regressions and behavior changes, while fixing the +various bugs and overflows. And like the "Harden file2str()" patch, this +patch does not fail when about to overflow, but truncates instead: there +is information available about this process, so return it to the caller; +also, we used INT_MAX as a limit, but a lower limit could be used. + +The easy changes: + +- Replace sprintf() with snprintf() (and check for truncation). + +- Replace "if (n == 0 && rbuf == 0)" with "if (n <= 0 && tot <= 0)" and + do break instead of return: it simplifies the code (only one place to + handle errors), and also guarantees that in the while loop either n or + tot is > 0 (or both), even if n is reset to 0 when about to overflow. + +- Remove the "if (n < 0)" block in the while loop: it is (and was) dead + code, since we enter the while loop only if n >= 0. + +- Rewrite the missing-null-terminator detection: in the original + function, if the size of the file is a multiple of 2047, a null- + terminator is appended even if the file is already null-terminated. + +- Replace "if (n <= 0 && !end_of_file)" with "if (n < 0 || tot <= 0)": + originally, it was equivalent to "if (n < 0)", but we added "tot <= 0" + to handle the first break of the while loop, and to guarantee that in + the rest of the function tot is > 0. + +- Double-force ("belt and suspenders") the null-termination of rbuf: + this is (and was) essential to the correctness of the function. + +- Replace the final "while" loop with a "for" loop that behaves just + like the preceding "for" loop: in the original function, this would + lead to unexpected results (for example, if rbuf is |\0|A|\0|, this + would return the array {"",NULL} but should return {"","A",NULL}; and + if rbuf is |A|\0|B| (should never happen because rbuf should be null- + terminated), this would make room for two pointers in ret, but would + write three pointers to ret). + +The hard changes: + +- Prevent the integer overflow of tot in the while loop, but unlike + file2str(), file2strvec() cannot let tot grow until it almost reaches + INT_MAX, because it needs more space for the pointers: this is why we + introduced ARG_LEN, which also guarantees that we can add "align" and + a few sizeof(char*)s to tot without overflowing. + +- Prevent the integer overflow of "tot + c + align": when INT_MAX is + (almost) reached, we write the maximal safe amount of pointers to ret + (ARG_LEN guarantees that there is always space for *ret = rbuf and the + NULL terminator). +[carnil: backport for 3.3.9: Add include for limits.h and use of MAX_INT] + +CVE: CVE-2018-1124 +Upstream-Status: Backport [https://gitlab.com/procps-ng/procps/commit/36c350f07c75aabf747fb833f52a234ae5781b20] + +Signed-off-by: Jagadeesh Krishnanjanappa <jkrishnanjanappa@mvista.com> +--- + proc/readproc.c | 53 ++++++++++++++++++++++++++++++++--------------------- + 1 file changed, 32 insertions(+), 21 deletions(-) + +diff -Naurp procps-ng-3.3.12_org/proc/readproc.c procps-ng-3.3.12/proc/readproc.c +--- procps-ng-3.3.12_org/proc/readproc.c 2016-07-09 14:49:25.825306872 -0700 ++++ procps-ng-3.3.12/proc/readproc.c 2018-07-24 00:46:49.366202531 -0700 +@@ -37,6 +37,7 @@ + #include <dirent.h> + #include <sys/types.h> + #include <sys/stat.h> ++#include <limits.h> + #ifdef WITH_SYSTEMD + #include <systemd/sd-login.h> + #endif +--- a/proc/readproc.c ++++ b/proc/readproc.c +@@ -600,11 +601,12 @@ static int file2str(const char *director + + static char** file2strvec(const char* directory, const char* what) { + char buf[2048]; /* read buf bytes at a time */ +- char *p, *rbuf = 0, *endbuf, **q, **ret; ++ char *p, *rbuf = 0, *endbuf, **q, **ret, *strp; + int fd, tot = 0, n, c, end_of_file = 0; + int align; + +- sprintf(buf, "%s/%s", directory, what); ++ const int len = snprintf(buf, sizeof buf, "%s/%s", directory, what); ++ if(len <= 0 || (size_t)len >= sizeof buf) return NULL; + fd = open(buf, O_RDONLY, 0); + if(fd==-1) return NULL; + +@@ -612,18 +614,23 @@ static char** file2strvec(const char* di + while ((n = read(fd, buf, sizeof buf - 1)) >= 0) { + if (n < (int)(sizeof buf - 1)) + end_of_file = 1; +- if (n == 0 && rbuf == 0) { +- close(fd); +- return NULL; /* process died between our open and read */ ++ if (n <= 0 && tot <= 0) { /* nothing read now, nothing read before */ ++ break; /* process died between our open and read */ + } +- if (n < 0) { +- if (rbuf) +- free(rbuf); +- close(fd); +- return NULL; /* read error */ ++ /* ARG_LEN is our guesstimated median length of a command-line argument ++ or environment variable (the minimum is 1, the maximum is 131072) */ ++ #define ARG_LEN 64 ++ if (tot >= INT_MAX / (ARG_LEN + (int)sizeof(char*)) * ARG_LEN - n) { ++ end_of_file = 1; /* integer overflow: null-terminate and break */ ++ n = 0; /* but tot > 0 */ + } +- if (end_of_file && (n == 0 || buf[n-1]))/* last read char not null */ ++ #undef ARG_LEN ++ if (end_of_file && ++ ((n > 0 && buf[n-1] != '\0') || /* last read char not null */ ++ (n <= 0 && rbuf[tot-1] != '\0'))) /* last read char not null */ + buf[n++] = '\0'; /* so append null-terminator */ ++ ++ if (n <= 0) break; /* unneeded (end_of_file = 1) but avoid realloc */ + rbuf = xrealloc(rbuf, tot + n); /* allocate more memory */ + memcpy(rbuf + tot, buf, n); /* copy buffer into it */ + tot += n; /* increment total byte ctr */ +@@ -631,29 +638,34 @@ static char** file2strvec(const char* di + break; + } + close(fd); +- if (n <= 0 && !end_of_file) { ++ if (n < 0 || tot <= 0) { /* error, or nothing read */ + if (rbuf) free(rbuf); + return NULL; /* read error */ + } ++ rbuf[tot-1] = '\0'; /* belt and suspenders (the while loop did it, too) */ + endbuf = rbuf + tot; /* count space for pointers */ + align = (sizeof(char*)-1) - ((tot + sizeof(char*)-1) & (sizeof(char*)-1)); +- for (c = 0, p = rbuf; p < endbuf; p++) { +- if (!*p || *p == '\n') ++ c = sizeof(char*); /* one extra for NULL term */ ++ for (p = rbuf; p < endbuf; p++) { ++ if (!*p || *p == '\n') { ++ if (c >= INT_MAX - (tot + (int)sizeof(char*) + align)) break; + c += sizeof(char*); ++ } + if (*p == '\n') + *p = 0; + } +- c += sizeof(char*); /* one extra for NULL term */ + + rbuf = xrealloc(rbuf, tot + c + align); /* make room for ptrs AT END */ + endbuf = rbuf + tot; /* addr just past data buf */ + q = ret = (char**) (endbuf+align); /* ==> free(*ret) to dealloc */ +- *q++ = p = rbuf; /* point ptrs to the strings */ +- endbuf--; /* do not traverse final NUL */ +- while (++p < endbuf) +- if (!*p) /* NUL char implies that */ +- *q++ = p+1; /* next string -> next char */ +- ++ for (strp = p = rbuf; p < endbuf; p++) { ++ if (!*p) { /* NUL char implies that */ ++ if (c < 2 * (int)sizeof(char*)) break; ++ c -= sizeof(char*); ++ *q++ = strp; /* point ptrs to the strings */ ++ strp = p+1; /* next string -> next char */ ++ } ++ } + *q = 0; /* null ptr list terminator */ + return ret; + } diff --git a/meta/recipes-extended/procps/procps_3.3.12.bb b/meta/recipes-extended/procps/procps_3.3.12.bb index ecf215fecf..6e15b0a5a0 100644 --- a/meta/recipes-extended/procps/procps_3.3.12.bb +++ b/meta/recipes-extended/procps/procps_3.3.12.bb @@ -14,6 +14,7 @@ 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://CVE-2018-1124.patch \ " SRC_URI[md5sum] = "957e42e8b193490b2111252e4a2b443c" |