From 16abcd90aefae8bdb9f7d80a555982dba6ca59b5 Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Fri, 13 Apr 2007 23:59:52 +0000 Subject: [PATCH] teach find_root_device to deal with /dev/ subdirs (by "Kirill K. Smirnov" ) --- coreutils/ls.c | 8 ++--- coreutils/rm.c | 2 +- include/libbb.h | 1 + libbb/concat_subpath_file.c | 2 +- libbb/find_root_device.c | 59 ++++++++++++++++++++++++++++++------- libbb/simplify_path.c | 11 ++++--- miscutils/devfsd.c | 2 +- networking/httpd.c | 10 +++---- shell/ash.c | 3 +- 9 files changed, 71 insertions(+), 27 deletions(-) diff --git a/coreutils/ls.c b/coreutils/ls.c index 7bbb19d6c..b9c07adf8 100644 --- a/coreutils/ls.c +++ b/coreutils/ls.c @@ -504,11 +504,11 @@ static struct dnode **list_dir(const char *path) /* are we going to list the file- it may be . or .. or a hidden file */ if (entry->d_name[0] == '.') { - if ((entry->d_name[1] == 0 || ( - entry->d_name[1] == '.' - && entry->d_name[2] == 0)) - && !(all_fmt & DISP_DOT)) + if ((!entry->d_name[1] || (entry->d_name[1] == '.' && !entry->d_name[2])) + && !(all_fmt & DISP_DOT) + ) { continue; + } if (!(all_fmt & DISP_HIDDEN)) continue; } diff --git a/coreutils/rm.c b/coreutils/rm.c index 61e3e7010..e29073db8 100644 --- a/coreutils/rm.c +++ b/coreutils/rm.c @@ -40,7 +40,7 @@ int rm_main(int argc, char **argv) do { const char *base = bb_get_last_path_component(*argv); - if ((base[0] == '.') && (!base[1] || ((base[1] == '.') && !base[2]))) { + if (DOT_OR_DOTDOT(base)) { bb_error_msg("cannot remove '.' or '..'"); } else if (remove_file(*argv, flags) >= 0) { continue; diff --git a/include/libbb.h b/include/libbb.h index 29ee8daae..212b048de 100644 --- a/include/libbb.h +++ b/include/libbb.h @@ -405,6 +405,7 @@ extern char *xasprintf(const char *format, ...) __attribute__ ((format (printf, #define NOT_LONE_DASH(s) ((s)[0] != '-' || (s)[1]) #define LONE_CHAR(s,c) ((s)[0] == (c) && !(s)[1]) #define NOT_LONE_CHAR(s,c) ((s)[0] != (c) || (s)[1]) +#define DOT_OR_DOTDOT(s) ((s)[0] == '.' && (!(s)[1] || ((s)[1] == '.' && !(s)[2]))) /* dmalloc will redefine these to it's own implementation. It is safe * to have the prototypes here unconditionally. */ diff --git a/libbb/concat_subpath_file.c b/libbb/concat_subpath_file.c index 6bbe49ab5..1c0058889 100644 --- a/libbb/concat_subpath_file.c +++ b/libbb/concat_subpath_file.c @@ -17,7 +17,7 @@ char *concat_subpath_file(const char *path, const char *f) { - if (f && *f == '.' && (!f[1] || (f[1] == '.' && !f[2]))) + if (f && DOT_OR_DOTDOT(f)) return NULL; return concat_path_file(path, f); } diff --git a/libbb/find_root_device.c b/libbb/find_root_device.c index ea360eae5..7182102c7 100644 --- a/libbb/find_root_device.c +++ b/libbb/find_root_device.c @@ -9,26 +9,65 @@ #include "libbb.h" -char *find_block_device(const char *path) +/* Find block device /dev/XXX which contains specified file + * We handle /dev/dir/dir/dir too, at a cost of ~80 more bytes code */ + +/* Do not reallocate all this stuff on each recursion */ +enum { DEVNAME_MAX = 256 }; +struct arena { + struct stat st; + dev_t dev; + /* Was PATH_MAX, but we recurse _/dev_. We can assume + * people are not crazy enough to have mega-deep tree there */ + char devpath[DEVNAME_MAX]; +}; + +static char *find_block_device_in_dir(struct arena *ap) { DIR *dir; struct dirent *entry; - struct stat st; - dev_t dev; - char *retpath=NULL; + char *retpath = NULL; + int len, rem; - if (stat(path, &st) || !(dir = opendir("/dev"))) + dir = opendir(ap->devpath); + if (!dir) return NULL; - dev = (st.st_mode & S_IFMT) == S_IFBLK ? st.st_rdev : st.st_dev; + + len = strlen(ap->devpath); + rem = DEVNAME_MAX-2 - len; + if (rem <= 0) + return NULL; + ap->devpath[len++] = '/'; + while ((entry = readdir(dir)) != NULL) { - char devpath[PATH_MAX]; - sprintf(devpath,"/dev/%s", entry->d_name); - if (!stat(devpath, &st) && S_ISBLK(st.st_mode) && st.st_rdev == dev) { - retpath = xstrdup(devpath); + safe_strncpy(ap->devpath + len, entry->d_name, rem); + if (stat(ap->devpath, &ap->st) != 0) + continue; + if (S_ISBLK(ap->st.st_mode) && ap->st.st_rdev == ap->dev) { + retpath = xstrdup(ap->devpath); break; } + if (S_ISDIR(ap->st.st_mode)) { + /* Do not recurse for '.' and '..' */ + if (DOT_OR_DOTDOT(entry->d_name)) + continue; + retpath = find_block_device_in_dir(ap); + if (retpath) + break; + } } closedir(dir); return retpath; } + +char *find_block_device(const char *path) +{ + struct arena a; + + if (stat(path, &a.st) != 0) + return NULL; + a.dev = S_ISBLK(a.st.st_mode) ? a.st.st_rdev : a.st.st_dev; + strcpy(a.devpath, "/dev"); + return find_block_device_in_dir(&a); +} diff --git a/libbb/simplify_path.c b/libbb/simplify_path.c index 7e68e3911..29e371df6 100644 --- a/libbb/simplify_path.c +++ b/libbb/simplify_path.c @@ -26,13 +26,16 @@ char *bb_simplify_path(const char *path) if (*p == '/') { if (*s == '/') { /* skip duplicate (or initial) slash */ continue; - } else if (*s == '.') { - if (s[1] == '/' || s[1] == 0) { /* remove extra '.' */ + } + if (*s == '.') { + if (s[1] == '/' || !s[1]) { /* remove extra '.' */ continue; - } else if ((s[1] == '.') && (s[2] == '/' || s[2] == 0)) { + } + if ((s[1] == '.') && (s[2] == '/' || !s[2])) { ++s; if (p > start) { - while (*--p != '/'); /* omit previous dir */ + while (*--p != '/') /* omit previous dir */ + continue; } continue; } diff --git a/miscutils/devfsd.c b/miscutils/devfsd.c index 0069b280e..d1a5163d2 100644 --- a/miscutils/devfsd.c +++ b/miscutils/devfsd.c @@ -1369,7 +1369,7 @@ static void dir_operation(int type, const char * dir_name, int var, unsigned lon while ( (de = readdir (dp) ) != NULL ) { - if(de->d_name && *de->d_name == '.' && (!de->d_name[1] || (de->d_name[1] == '.' && !de->d_name[2]))) + if(de->d_name && DOT_OR_DOTDOT(de->d_name)) continue; snprintf (path, sizeof (path), "%s/%s", dir_name, de->d_name); debug_msg_logger(LOG_ERR, "%s: %s", __FUNCTION__, path); diff --git a/networking/httpd.c b/networking/httpd.c index d80df937a..1f7c886de 100644 --- a/networking/httpd.c +++ b/networking/httpd.c @@ -1573,7 +1573,7 @@ static void handleIncoming(void) } /* algorithm stolen from libbb bb_simplify_path(), - but don't strdup and reducing trailing slash and protect out root */ + * but don't strdup and reducing trailing slash and protect out root */ purl = test = url; do { if (*purl == '/') { @@ -1583,18 +1583,18 @@ static void handleIncoming(void) } if (*test == '.') { /* skip extra '.' */ - if (test[1] == '/' || test[1] == 0) { + if (test[1] == '/' || !test[1]) { continue; - } else + } /* '..': be careful */ - if (test[1] == '.' && (test[2] == '/' || test[2] == 0)) { + if (test[1] == '.' && (test[2] == '/' || !test[2])) { ++test; if (purl == url) { /* protect out root */ goto BAD_REQUEST; } while (*--purl != '/') /* omit previous dir */; - continue; + continue; } } } diff --git a/shell/ash.c b/shell/ash.c index f8207a6cc..63f039df4 100644 --- a/shell/ash.c +++ b/shell/ash.c @@ -2293,7 +2293,8 @@ updatepwd(const char *dir) break; } break; - } else if (p[1] == '\0') + } + if (p[1] == '\0') break; /* fall through */ default: