diff options
Diffstat (limited to 'tools/patch/patches/020-CVE-2018-1000156.patch')
| -rw-r--r-- | tools/patch/patches/020-CVE-2018-1000156.patch | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/tools/patch/patches/020-CVE-2018-1000156.patch b/tools/patch/patches/020-CVE-2018-1000156.patch new file mode 100644 index 0000000000..99dfe54075 --- /dev/null +++ b/tools/patch/patches/020-CVE-2018-1000156.patch @@ -0,0 +1,142 @@ +From b3a0ca3deed00334f9feece43f76776b6a168e47 Mon Sep 17 00:00:00 2001 +From: Andreas Gruenbacher <agruen@gnu.org> +Date: Fri, 6 Apr 2018 12:14:49 +0200 +Subject: [PATCH] Fix arbitrary command execution in ed-style patches + (CVE-2018-1000156) + +* src/pch.c (do_ed_script): Write ed script to a temporary file instead +of piping it to ed: this will cause ed to abort on invalid commands +instead of rejecting them and carrying on. +* tests/ed-style: New test case. +* tests/Makefile.am (TESTS): Add test case. +--- + src/pch.c | 89 +++++++++++++++++++++++++++++++++++++++++-------------- + 1 file changed, 66 insertions(+), 23 deletions(-) + +--- a/src/pch.c ++++ b/src/pch.c +@@ -33,6 +33,7 @@ + # include <io.h> + #endif + #include <safe.h> ++#include <sys/wait.h> + + #define INITHUNKMAX 125 /* initial dynamic allocation size */ + +@@ -2389,22 +2390,28 @@ do_ed_script (char const *inname, char c + static char const editor_program[] = EDITOR_PROGRAM; + + file_offset beginning_of_this_line; +- FILE *pipefp = 0; + size_t chars_read; ++ FILE *tmpfp = 0; ++ char const *tmpname; ++ int tmpfd; ++ pid_t pid; ++ ++ if (! dry_run && ! skip_rest_of_patch) ++ { ++ /* Write ed script to a temporary file. This causes ed to abort on ++ invalid commands such as when line numbers or ranges exceed the ++ number of available lines. When ed reads from a pipe, it rejects ++ invalid commands and treats the next line as a new command, which ++ can lead to arbitrary command execution. */ ++ ++ tmpfd = make_tempfile (&tmpname, 'e', NULL, O_RDWR | O_BINARY, 0); ++ if (tmpfd == -1) ++ pfatal ("Can't create temporary file %s", quotearg (tmpname)); ++ tmpfp = fdopen (tmpfd, "w+b"); ++ if (! tmpfp) ++ pfatal ("Can't open stream for file %s", quotearg (tmpname)); ++ } + +- if (! dry_run && ! skip_rest_of_patch) { +- int exclusive = *outname_needs_removal ? 0 : O_EXCL; +- assert (! inerrno); +- *outname_needs_removal = true; +- copy_file (inname, outname, 0, exclusive, instat.st_mode, true); +- sprintf (buf, "%s %s%s", editor_program, +- verbosity == VERBOSE ? "" : "- ", +- outname); +- fflush (stdout); +- pipefp = popen(buf, binary_transput ? "wb" : "w"); +- if (!pipefp) +- pfatal ("Can't open pipe to %s", quotearg (buf)); +- } + for (;;) { + char ed_command_letter; + beginning_of_this_line = file_tell (pfp); +@@ -2415,14 +2422,14 @@ do_ed_script (char const *inname, char c + } + ed_command_letter = get_ed_command_letter (buf); + if (ed_command_letter) { +- if (pipefp) +- if (! fwrite (buf, sizeof *buf, chars_read, pipefp)) ++ if (tmpfp) ++ if (! fwrite (buf, sizeof *buf, chars_read, tmpfp)) + write_fatal (); + if (ed_command_letter != 'd' && ed_command_letter != 's') { + p_pass_comments_through = true; + while ((chars_read = get_line ()) != 0) { +- if (pipefp) +- if (! fwrite (buf, sizeof *buf, chars_read, pipefp)) ++ if (tmpfp) ++ if (! fwrite (buf, sizeof *buf, chars_read, tmpfp)) + write_fatal (); + if (chars_read == 2 && strEQ (buf, ".\n")) + break; +@@ -2435,13 +2442,49 @@ do_ed_script (char const *inname, char c + break; + } + } +- if (!pipefp) ++ if (!tmpfp) + return; +- if (fwrite ("w\nq\n", sizeof (char), (size_t) 4, pipefp) == 0 +- || fflush (pipefp) != 0) ++ if (fwrite ("w\nq\n", sizeof (char), (size_t) 4, tmpfp) == 0 ++ || fflush (tmpfp) != 0) + write_fatal (); +- if (pclose (pipefp) != 0) +- fatal ("%s FAILED", editor_program); ++ ++ if (lseek (tmpfd, 0, SEEK_SET) == -1) ++ pfatal ("Can't rewind to the beginning of file %s", quotearg (tmpname)); ++ ++ if (! dry_run && ! skip_rest_of_patch) { ++ int exclusive = *outname_needs_removal ? 0 : O_EXCL; ++ *outname_needs_removal = true; ++ if (inerrno != ENOENT) ++ { ++ *outname_needs_removal = true; ++ copy_file (inname, outname, 0, exclusive, instat.st_mode, true); ++ } ++ sprintf (buf, "%s %s%s", editor_program, ++ verbosity == VERBOSE ? "" : "- ", ++ outname); ++ fflush (stdout); ++ ++ pid = fork(); ++ if (pid == -1) ++ pfatal ("Can't fork"); ++ else if (pid == 0) ++ { ++ dup2 (tmpfd, 0); ++ execl ("/bin/sh", "sh", "-c", buf, (char *) 0); ++ _exit (2); ++ } ++ else ++ { ++ int wstatus; ++ if (waitpid (pid, &wstatus, 0) == -1 ++ || ! WIFEXITED (wstatus) ++ || WEXITSTATUS (wstatus) != 0) ++ fatal ("%s FAILED", editor_program); ++ } ++ } ++ ++ fclose (tmpfp); ++ safe_unlink (tmpname); + + if (ofp) + { |