diff options
Diffstat (limited to 'gnu/packages/patches/libarchive-fix-filesystem-attacks.patch')
| -rw-r--r-- | gnu/packages/patches/libarchive-fix-filesystem-attacks.patch | 445 |
1 files changed, 0 insertions, 445 deletions
diff --git a/gnu/packages/patches/libarchive-fix-filesystem-attacks.patch b/gnu/packages/patches/libarchive-fix-filesystem-attacks.patch deleted file mode 100644 index bce63d5e4e..0000000000 --- a/gnu/packages/patches/libarchive-fix-filesystem-attacks.patch +++ /dev/null @@ -1,445 +0,0 @@ -This patch fixes two bugs that allow attackers to overwrite or change -the permissions of arbitrary files: - -https://github.com/libarchive/libarchive/issues/745 -https://github.com/libarchive/libarchive/issues/746 - -Patch copied from upstream repository: - -https://github.com/libarchive/libarchive/commit/dfd6b54ce33960e420fb206d8872fb759b577ad9 - -From dfd6b54ce33960e420fb206d8872fb759b577ad9 Mon Sep 17 00:00:00 2001 -From: Tim Kientzle <kientzle@acm.org> -Date: Sun, 11 Sep 2016 13:21:57 -0700 -Subject: [PATCH] Fixes for Issue #745 and Issue #746 from Doran Moppert. - ---- - libarchive/archive_write_disk_posix.c | 294 ++++++++++++++++++++++++++-------- - 1 file changed, 227 insertions(+), 67 deletions(-) - -diff --git a/libarchive/archive_write_disk_posix.c b/libarchive/archive_write_disk_posix.c -index 8f0421e..abe1a86 100644 ---- a/libarchive/archive_write_disk_posix.c -+++ b/libarchive/archive_write_disk_posix.c -@@ -326,12 +326,14 @@ struct archive_write_disk { - - #define HFS_BLOCKS(s) ((s) >> 12) - -+static int check_symlinks_fsobj(char *path, int *error_number, struct archive_string *error_string, int flags); - static int check_symlinks(struct archive_write_disk *); - static int create_filesystem_object(struct archive_write_disk *); - static struct fixup_entry *current_fixup(struct archive_write_disk *, const char *pathname); - #if defined(HAVE_FCHDIR) && defined(PATH_MAX) - static void edit_deep_directories(struct archive_write_disk *ad); - #endif -+static int cleanup_pathname_fsobj(char *path, int *error_number, struct archive_string *error_string, int flags); - static int cleanup_pathname(struct archive_write_disk *); - static int create_dir(struct archive_write_disk *, char *); - static int create_parent_dir(struct archive_write_disk *, char *); -@@ -2014,6 +2016,10 @@ create_filesystem_object(struct archive_write_disk *a) - const char *linkname; - mode_t final_mode, mode; - int r; -+ /* these for check_symlinks_fsobj */ -+ char *linkname_copy; /* non-const copy of linkname */ -+ struct archive_string error_string; -+ int error_number; - - /* We identify hard/symlinks according to the link names. */ - /* Since link(2) and symlink(2) don't handle modes, we're done here. */ -@@ -2022,6 +2028,27 @@ create_filesystem_object(struct archive_write_disk *a) - #if !HAVE_LINK - return (EPERM); - #else -+ archive_string_init(&error_string); -+ linkname_copy = strdup(linkname); -+ if (linkname_copy == NULL) { -+ return (EPERM); -+ } -+ /* TODO: consider using the cleaned-up path as the link target? */ -+ r = cleanup_pathname_fsobj(linkname_copy, &error_number, &error_string, a->flags); -+ if (r != ARCHIVE_OK) { -+ archive_set_error(&a->archive, error_number, "%s", error_string.s); -+ free(linkname_copy); -+ /* EPERM is more appropriate than error_number for our callers */ -+ return (EPERM); -+ } -+ r = check_symlinks_fsobj(linkname_copy, &error_number, &error_string, a->flags); -+ if (r != ARCHIVE_OK) { -+ archive_set_error(&a->archive, error_number, "%s", error_string.s); -+ free(linkname_copy); -+ /* EPERM is more appropriate than error_number for our callers */ -+ return (EPERM); -+ } -+ free(linkname_copy); - r = link(linkname, a->name) ? errno : 0; - /* - * New cpio and pax formats allow hardlink entries -@@ -2362,115 +2389,228 @@ current_fixup(struct archive_write_disk *a, const char *pathname) - * recent paths. - */ - /* TODO: Extend this to support symlinks on Windows Vista and later. */ -+ -+/* -+ * Checks the given path to see if any elements along it are symlinks. Returns -+ * ARCHIVE_OK if there are none, otherwise puts an error in errmsg. -+ */ - static int --check_symlinks(struct archive_write_disk *a) -+check_symlinks_fsobj(char *path, int *error_number, struct archive_string *error_string, int flags) - { - #if !defined(HAVE_LSTAT) - /* Platform doesn't have lstat, so we can't look for symlinks. */ - (void)a; /* UNUSED */ -+ (void)path; /* UNUSED */ -+ (void)error_number; /* UNUSED */ -+ (void)error_string; /* UNUSED */ -+ (void)flags; /* UNUSED */ - return (ARCHIVE_OK); - #else -- char *pn; -+ int res = ARCHIVE_OK; -+ char *tail; -+ char *head; -+ int last; - char c; - int r; - struct stat st; -+ int restore_pwd; -+ -+ /* Nothing to do here if name is empty */ -+ if(path[0] == '\0') -+ return (ARCHIVE_OK); - - /* - * Guard against symlink tricks. Reject any archive entry whose - * destination would be altered by a symlink. -+ * -+ * Walk the filename in chunks separated by '/'. For each segment: -+ * - if it doesn't exist, continue -+ * - if it's symlink, abort or remove it -+ * - if it's a directory and it's not the last chunk, cd into it -+ * As we go: -+ * head points to the current (relative) path -+ * tail points to the temporary \0 terminating the segment we're currently examining -+ * c holds what used to be in *tail -+ * last is 1 if this is the last tail - */ -- /* Whatever we checked last time doesn't need to be re-checked. */ -- pn = a->name; -- if (archive_strlen(&(a->path_safe)) > 0) { -- char *p = a->path_safe.s; -- while ((*pn != '\0') && (*p == *pn)) -- ++p, ++pn; -- } -+ restore_pwd = open(".", O_RDONLY | O_BINARY | O_CLOEXEC); -+ __archive_ensure_cloexec_flag(restore_pwd); -+ if (restore_pwd < 0) -+ return (ARCHIVE_FATAL); -+ head = path; -+ tail = path; -+ last = 0; -+ /* TODO: reintroduce a safe cache here? */ - /* Skip the root directory if the path is absolute. */ -- if(pn == a->name && pn[0] == '/') -- ++pn; -- c = pn[0]; -- /* Keep going until we've checked the entire name. */ -- while (pn[0] != '\0' && (pn[0] != '/' || pn[1] != '\0')) { -+ if(tail == path && tail[0] == '/') -+ ++tail; -+ /* Keep going until we've checked the entire name. -+ * head, tail, path all alias the same string, which is -+ * temporarily zeroed at tail, so be careful restoring the -+ * stashed (c=tail[0]) for error messages. -+ * Exiting the loop with break is okay; continue is not. -+ */ -+ while (!last) { -+ /* Skip the separator we just consumed, plus any adjacent ones */ -+ while (*tail == '/') -+ ++tail; - /* Skip the next path element. */ -- while (*pn != '\0' && *pn != '/') -- ++pn; -- c = pn[0]; -- pn[0] = '\0'; -+ while (*tail != '\0' && *tail != '/') -+ ++tail; -+ /* is this the last path component? */ -+ last = (tail[0] == '\0') || (tail[0] == '/' && tail[1] == '\0'); -+ /* temporarily truncate the string here */ -+ c = tail[0]; -+ tail[0] = '\0'; - /* Check that we haven't hit a symlink. */ -- r = lstat(a->name, &st); -+ r = lstat(head, &st); - if (r != 0) { -+ tail[0] = c; - /* We've hit a dir that doesn't exist; stop now. */ - if (errno == ENOENT) { - break; - } else { -- /* Note: This effectively disables deep directory -+ /* Treat any other error as fatal - best to be paranoid here -+ * Note: This effectively disables deep directory - * support when security checks are enabled. - * Otherwise, very long pathnames that trigger - * an error here could evade the sandbox. - * TODO: We could do better, but it would probably - * require merging the symlink checks with the - * deep-directory editing. */ -- return (ARCHIVE_FAILED); -+ if (error_number) *error_number = errno; -+ if (error_string) -+ archive_string_sprintf(error_string, -+ "Could not stat %s", -+ path); -+ res = ARCHIVE_FAILED; -+ break; -+ } -+ } else if (S_ISDIR(st.st_mode)) { -+ if (!last) { -+ if (chdir(head) != 0) { -+ tail[0] = c; -+ if (error_number) *error_number = errno; -+ if (error_string) -+ archive_string_sprintf(error_string, -+ "Could not chdir %s", -+ path); -+ res = (ARCHIVE_FATAL); -+ break; -+ } -+ /* Our view is now from inside this dir: */ -+ head = tail + 1; - } - } else if (S_ISLNK(st.st_mode)) { -- if (c == '\0') { -+ if (last) { - /* - * Last element is symlink; remove it - * so we can overwrite it with the - * item being extracted. - */ -- if (unlink(a->name)) { -- archive_set_error(&a->archive, errno, -- "Could not remove symlink %s", -- a->name); -- pn[0] = c; -- return (ARCHIVE_FAILED); -+ if (unlink(head)) { -+ tail[0] = c; -+ if (error_number) *error_number = errno; -+ if (error_string) -+ archive_string_sprintf(error_string, -+ "Could not remove symlink %s", -+ path); -+ res = ARCHIVE_FAILED; -+ break; - } -- a->pst = NULL; - /* - * Even if we did remove it, a warning - * is in order. The warning is silly, - * though, if we're just replacing one - * symlink with another symlink. - */ -- if (!S_ISLNK(a->mode)) { -- archive_set_error(&a->archive, 0, -- "Removing symlink %s", -- a->name); -+ tail[0] = c; -+ /* FIXME: not sure how important this is to restore -+ if (!S_ISLNK(path)) { -+ if (error_number) *error_number = 0; -+ if (error_string) -+ archive_string_sprintf(error_string, -+ "Removing symlink %s", -+ path); - } -+ */ - /* Symlink gone. No more problem! */ -- pn[0] = c; -- return (0); -- } else if (a->flags & ARCHIVE_EXTRACT_UNLINK) { -+ res = ARCHIVE_OK; -+ break; -+ } else if (flags & ARCHIVE_EXTRACT_UNLINK) { - /* User asked us to remove problems. */ -- if (unlink(a->name) != 0) { -- archive_set_error(&a->archive, 0, -- "Cannot remove intervening symlink %s", -- a->name); -- pn[0] = c; -- return (ARCHIVE_FAILED); -+ if (unlink(head) != 0) { -+ tail[0] = c; -+ if (error_number) *error_number = 0; -+ if (error_string) -+ archive_string_sprintf(error_string, -+ "Cannot remove intervening symlink %s", -+ path); -+ res = ARCHIVE_FAILED; -+ break; - } -- a->pst = NULL; -+ tail[0] = c; - } else { -- archive_set_error(&a->archive, 0, -- "Cannot extract through symlink %s", -- a->name); -- pn[0] = c; -- return (ARCHIVE_FAILED); -+ tail[0] = c; -+ if (error_number) *error_number = 0; -+ if (error_string) -+ archive_string_sprintf(error_string, -+ "Cannot extract through symlink %s", -+ path); -+ res = ARCHIVE_FAILED; -+ break; - } - } -- pn[0] = c; -- if (pn[0] != '\0') -- pn++; /* Advance to the next segment. */ -+ /* be sure to always maintain this */ -+ tail[0] = c; -+ if (tail[0] != '\0') -+ tail++; /* Advance to the next segment. */ - } -- pn[0] = c; -- /* We've checked and/or cleaned the whole path, so remember it. */ -- archive_strcpy(&a->path_safe, a->name); -- return (ARCHIVE_OK); -+ /* Catches loop exits via break */ -+ tail[0] = c; -+#ifdef HAVE_FCHDIR -+ /* If we changed directory above, restore it here. */ -+ if (restore_pwd >= 0) { -+ r = fchdir(restore_pwd); -+ if (r != 0) { -+ if(error_number) *error_number = errno; -+ if(error_string) -+ archive_string_sprintf(error_string, -+ "chdir() failure"); -+ } -+ close(restore_pwd); -+ restore_pwd = -1; -+ if (r != 0) { -+ res = (ARCHIVE_FATAL); -+ } -+ } -+#endif -+ /* TODO: reintroduce a safe cache here? */ -+ return res; - #endif - } - -+/* -+ * Check a->name for symlinks, returning ARCHIVE_OK if its clean, otherwise -+ * calls archive_set_error and returns ARCHIVE_{FATAL,FAILED} -+ */ -+static int -+check_symlinks(struct archive_write_disk *a) -+{ -+ struct archive_string error_string; -+ int error_number; -+ int rc; -+ archive_string_init(&error_string); -+ rc = check_symlinks_fsobj(a->name, &error_number, &error_string, a->flags); -+ if (rc != ARCHIVE_OK) { -+ archive_set_error(&a->archive, error_number, "%s", error_string.s); -+ } -+ archive_string_free(&error_string); -+ a->pst = NULL; /* to be safe */ -+ return rc; -+} -+ -+ - #if defined(__CYGWIN__) - /* - * 1. Convert a path separator from '\' to '/' . -@@ -2544,15 +2684,17 @@ cleanup_pathname_win(struct archive_write_disk *a) - * is set) if the path is absolute. - */ - static int --cleanup_pathname(struct archive_write_disk *a) -+cleanup_pathname_fsobj(char *path, int *error_number, struct archive_string *error_string, int flags) - { - char *dest, *src; - char separator = '\0'; - -- dest = src = a->name; -+ dest = src = path; - if (*src == '\0') { -- archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC, -- "Invalid empty pathname"); -+ if (error_number) *error_number = ARCHIVE_ERRNO_MISC; -+ if (error_string) -+ archive_string_sprintf(error_string, -+ "Invalid empty pathname"); - return (ARCHIVE_FAILED); - } - -@@ -2561,9 +2703,11 @@ cleanup_pathname(struct archive_write_disk *a) - #endif - /* Skip leading '/'. */ - if (*src == '/') { -- if (a->flags & ARCHIVE_EXTRACT_SECURE_NOABSOLUTEPATHS) { -- archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC, -- "Path is absolute"); -+ if (flags & ARCHIVE_EXTRACT_SECURE_NOABSOLUTEPATHS) { -+ if (error_number) *error_number = ARCHIVE_ERRNO_MISC; -+ if (error_string) -+ archive_string_sprintf(error_string, -+ "Path is absolute"); - return (ARCHIVE_FAILED); - } - -@@ -2590,10 +2734,11 @@ cleanup_pathname(struct archive_write_disk *a) - } else if (src[1] == '.') { - if (src[2] == '/' || src[2] == '\0') { - /* Conditionally warn about '..' */ -- if (a->flags & ARCHIVE_EXTRACT_SECURE_NODOTDOT) { -- archive_set_error(&a->archive, -- ARCHIVE_ERRNO_MISC, -- "Path contains '..'"); -+ if (flags & ARCHIVE_EXTRACT_SECURE_NODOTDOT) { -+ if (error_number) *error_number = ARCHIVE_ERRNO_MISC; -+ if (error_string) -+ archive_string_sprintf(error_string, -+ "Path contains '..'"); - return (ARCHIVE_FAILED); - } - } -@@ -2624,7 +2769,7 @@ cleanup_pathname(struct archive_write_disk *a) - * We've just copied zero or more path elements, not including the - * final '/'. - */ -- if (dest == a->name) { -+ if (dest == path) { - /* - * Nothing got copied. The path must have been something - * like '.' or '/' or './' or '/././././/./'. -@@ -2639,6 +2784,21 @@ cleanup_pathname(struct archive_write_disk *a) - return (ARCHIVE_OK); - } - -+static int -+cleanup_pathname(struct archive_write_disk *a) -+{ -+ struct archive_string error_string; -+ int error_number; -+ int rc; -+ archive_string_init(&error_string); -+ rc = cleanup_pathname_fsobj(a->name, &error_number, &error_string, a->flags); -+ if (rc != ARCHIVE_OK) { -+ archive_set_error(&a->archive, error_number, "%s", error_string.s); -+ } -+ archive_string_free(&error_string); -+ return rc; -+} -+ - /* - * Create the parent directory of the specified path, assuming path - * is already in mutable storage. |