diff options
Diffstat (limited to 'tools/patch/patches/050-CVE-2019-13636.patch')
| -rw-r--r-- | tools/patch/patches/050-CVE-2019-13636.patch | 108 |
1 files changed, 108 insertions, 0 deletions
diff --git a/tools/patch/patches/050-CVE-2019-13636.patch b/tools/patch/patches/050-CVE-2019-13636.patch new file mode 100644 index 0000000000..e62c3d4175 --- /dev/null +++ b/tools/patch/patches/050-CVE-2019-13636.patch @@ -0,0 +1,108 @@ +From dce4683cbbe107a95f1f0d45fabc304acfb5d71a Mon Sep 17 00:00:00 2001 +From: Andreas Gruenbacher <agruen@gnu.org> +Date: Mon, 15 Jul 2019 16:21:48 +0200 +Subject: Don't follow symlinks unless --follow-symlinks is given + +* src/inp.c (plan_a, plan_b), src/util.c (copy_to_fd, copy_file, +append_to_file): Unless the --follow-symlinks option is given, open files with +the O_NOFOLLOW flag to avoid following symlinks. So far, we were only doing +that consistently for input files. +* src/util.c (create_backup): When creating empty backup files, (re)create them +with O_CREAT | O_EXCL to avoid following symlinks in that case as well. +--- + src/inp.c | 12 ++++++++++-- + src/util.c | 14 +++++++++++--- + 2 files changed, 21 insertions(+), 5 deletions(-) + +diff --git a/src/inp.c b/src/inp.c +index 32d0919..22d7473 100644 +--- a/src/inp.c ++++ b/src/inp.c +@@ -238,8 +238,13 @@ plan_a (char const *filename) + { + if (S_ISREG (instat.st_mode)) + { +- int ifd = safe_open (filename, O_RDONLY|binary_transput, 0); ++ int flags = O_RDONLY | binary_transput; + size_t buffered = 0, n; ++ int ifd; ++ ++ if (! follow_symlinks) ++ flags |= O_NOFOLLOW; ++ ifd = safe_open (filename, flags, 0); + if (ifd < 0) + pfatal ("can't open file %s", quotearg (filename)); + +@@ -340,6 +345,7 @@ plan_a (char const *filename) + static void + plan_b (char const *filename) + { ++ int flags = O_RDONLY | binary_transput; + int ifd; + FILE *ifp; + int c; +@@ -353,7 +359,9 @@ plan_b (char const *filename) + + if (instat.st_size == 0) + filename = NULL_DEVICE; +- if ((ifd = safe_open (filename, O_RDONLY | binary_transput, 0)) < 0 ++ if (! follow_symlinks) ++ flags |= O_NOFOLLOW; ++ if ((ifd = safe_open (filename, flags, 0)) < 0 + || ! (ifp = fdopen (ifd, binary_transput ? "rb" : "r"))) + pfatal ("Can't open file %s", quotearg (filename)); + if (TMPINNAME_needs_removal) +diff --git a/src/util.c b/src/util.c +index 1cc08ba..fb38307 100644 +--- a/src/util.c ++++ b/src/util.c +@@ -388,7 +388,7 @@ create_backup (char const *to, const struct stat *to_st, bool leave_original) + + try_makedirs_errno = ENOENT; + safe_unlink (bakname); +- while ((fd = safe_open (bakname, O_CREAT | O_WRONLY | O_TRUNC, 0666)) < 0) ++ while ((fd = safe_open (bakname, O_CREAT | O_EXCL | O_WRONLY | O_TRUNC, 0666)) < 0) + { + if (errno != try_makedirs_errno) + pfatal ("Can't create file %s", quotearg (bakname)); +@@ -579,10 +579,13 @@ create_file (char const *file, int open_flags, mode_t mode, + static void + copy_to_fd (const char *from, int tofd) + { ++ int from_flags = O_RDONLY | O_BINARY; + int fromfd; + ssize_t i; + +- if ((fromfd = safe_open (from, O_RDONLY | O_BINARY, 0)) < 0) ++ if (! follow_symlinks) ++ from_flags |= O_NOFOLLOW; ++ if ((fromfd = safe_open (from, from_flags, 0)) < 0) + pfatal ("Can't reopen file %s", quotearg (from)); + while ((i = read (fromfd, buf, bufsize)) != 0) + { +@@ -625,6 +628,8 @@ copy_file (char const *from, char const *to, struct stat *tost, + else + { + assert (S_ISREG (mode)); ++ if (! follow_symlinks) ++ to_flags |= O_NOFOLLOW; + tofd = create_file (to, O_WRONLY | O_BINARY | to_flags, mode, + to_dir_known_to_exist); + copy_to_fd (from, tofd); +@@ -640,9 +645,12 @@ copy_file (char const *from, char const *to, struct stat *tost, + void + append_to_file (char const *from, char const *to) + { ++ int to_flags = O_WRONLY | O_APPEND | O_BINARY; + int tofd; + +- if ((tofd = safe_open (to, O_WRONLY | O_BINARY | O_APPEND, 0)) < 0) ++ if (! follow_symlinks) ++ to_flags |= O_NOFOLLOW; ++ if ((tofd = safe_open (to, to_flags, 0)) < 0) + pfatal ("Can't reopen file %s", quotearg (to)); + copy_to_fd (from, tofd); + if (close (tofd) != 0) +-- +cgit v1.0-41-gc330 + |