lsfd: use only "/proc/#/maps" file

* do not read /proc/#/map_files symlinks
* use paths from /proc/#/maps
* do not maintain map entries

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/misc-utils/lsfd.c b/misc-utils/lsfd.c
index 2b7b1608f11c37948259cf03b08975602a2ec4eb..35abd7d8c633df07259b78918bbca1251160b358 100644 (file)
--- a/misc-utils/lsfd.c
+++ b/misc-utils/lsfd.c
@@ -52,17 +52,6 @@ static int kcmp(pid_t pid1, pid_t pid2, int type,
 
 #include "lsfd.h"
 
-
-/*
- * /proc/$pid/maps entries
- */
-struct map {
-       struct list_head maps;
-       unsigned long mem_addr_start;
-       unsigned long long file_offset;
-       unsigned int read:1, write:1, exec:1, shared:1;
-};
-
 /*
  * /proc/$pid/mountinfo entries
  */
@@ -378,82 +367,6 @@ static struct file *collect_file_symlink(struct path_cxt *pc,
        return f;
 }
 
-static struct map *find_map(struct list_head *maps, unsigned long start_addr)
-{
-       struct list_head *m;
-
-       list_for_each(m, maps) {
-               struct map *map = list_entry(m, struct map, maps);
-               if (map->mem_addr_start == start_addr)
-                       return map;
-       }
-       return NULL;
-}
-
-static struct file *collect_mem_file(struct proc *proc, int dd, struct dirent *dp,
-                                    void *data)
-{
-       struct list_head *maps = data;
-       struct stat sb;
-       ssize_t len;
-       char sym[PATH_MAX];
-       struct file *f;
-       uint64_t start, end;
-       struct map *map;
-       enum association assoc;
-       mode_t mode = 0;
-
-       if (fstatat(dd, dp->d_name, &sb, 0) < 0)
-               return NULL;
-
-       memset(sym, 0, sizeof(sym));
-       if ((len = readlinkat(dd, dp->d_name, sym, sizeof(sym) - 1)) < 0)
-               return NULL;
-
-
-       map = NULL;
-       if (sscanf(dp->d_name, "%" SCNx64 "-%" SCNx64, &start, &end) == 2)
-               map = find_map(maps, start);
-
-       assoc = (map && map->shared)? ASSOC_SHM: ASSOC_MEM;
-
-       f = new_file(proc, stat2class(&sb));
-       file_set_path(f, &sb, sym, -assoc);
-
-       if (map)
-               mode = (map->read? S_IRUSR: 0) | (map->write? S_IWUSR: 0) | (map->exec? S_IXUSR: 0);
-
-       f->map_start = start;
-       f->map_end = end;
-       f->pos = map ?  map->file_offset : 0;
-       f->mode = mode;
-
-       file_init_content(f);
-
-       return f;
-}
-
-static void collect_fd_files_generic(struct proc *proc, const char *proc_template,
-                                    struct file *(*collector)(struct proc *,int, struct dirent *, void *),
-                                    void *data)
-{
-       DIR *dirp;
-       int dd;
-       struct dirent *dp;
-
-       dirp = opendirf(proc_template, proc->pid);
-       if (!dirp)
-               return;
-
-       if ((dd = dirfd(dirp)) < 0 )
-               return;
-
-       while ((dp = xreaddir(dirp)))
-               collector(proc, dd, dp, data);
-
-       closedir(dirp);
-}
-
 /* read symlinks from /proc/#/fd
  */
 static void collect_fd_files(struct path_cxt *pc, struct proc *proc)
@@ -473,85 +386,74 @@ static void collect_fd_files(struct path_cxt *pc, struct proc *proc)
        }
 }
 
-static struct map* new_map(unsigned long mem_addr_start, unsigned long long file_offset,
-                           int r, int w, int x, int s)
+static void parse_maps_line(char *buf, struct proc *proc)
 {
-       struct map *map = xcalloc(1, sizeof(*map));
-
-       INIT_LIST_HEAD(&map->maps);
+       uint64_t start, end, offset, ino;
+       unsigned long major, minor;
+       enum association assoc = ASSOC_MEM;
+       struct stat sb;
+       struct file *f;
+       char *path, modestr[5];
 
-       map->mem_addr_start = mem_addr_start;
-       map->file_offset = file_offset;
+       /* ignore non-path entries */
+       path = strchr(buf, '/');
+       if (!path)
+               return;
+       rtrim_whitespace((unsigned char *) path);
 
-       map->read   = r;
-       map->write  = w;
-       map->exec   = x;
-       map->shared = s;
+       /* first try the path */
+       if (stat(path, &sb) < 0)
+               return;
 
-       return map;
-}
+       /* read rest of the map */
+       if (sscanf(buf, "%"SCNx64               /* start */
+                       "-%"SCNx64              /* end */
+                       " %4[^ ]"               /* mode */
+                       " %"SCNx64              /* offset */
+                       " %lx:%lx"              /* maj:min */
+                       " %"SCNu64,             /* inode */
 
-static void free_map(struct map *map)
-{
-       free(map);
-}
+                       &start, &end, modestr, &offset,
+                       &major, &minor, &ino) != 7)
+               return;
 
-static void read_maps(struct list_head *maps_list, FILE *maps_fp)
-{
-       /* Taken from proc(5):
-        * address           perms offset  dev   inode       pathname
-        * 00400000-00452000 r-xp 00000000 08:02 173521      /usr/bin/dbus-daemon
-        * ... */
-
-       char line[PATH_MAX + 128];
-       unsigned long start, end;
-       char r, w, x, s;
-       unsigned long long file_offset;
-       unsigned long major;
-       unsigned long minor;
-       long unsigned inode;
+       f = new_file(proc, stat2class(&sb));
+       if (!f)
+               return;
 
-       while (fgets(line, sizeof(line), maps_fp)) {
-               struct map *map;
+       file_set_path(f, &sb, path, -assoc);
 
-               if (sscanf(line, "%lx-%lx %c%c%c%c %llx %lx:%lx %lu %*[^\n]",
-                          &start, &end, &r, &w, &x, &s, &file_offset,
-                          &major, &minor, &inode) != 10)
-                       continue;
-               map = new_map(start, file_offset, r == 'r', w == 'w', x == 'x', s == 's');
-               list_add_tail(&map->maps, maps_list);
-       }
-}
+       if (modestr[0] == 'r')
+               f->mode |= S_IRUSR;
+       if (modestr[1] == 'w')
+               f->mode |= S_IWUSR;
+       if (modestr[2] == 'x')
+               f->mode |= S_IXUSR;
+       if (modestr[3] == 's')
+               assoc = ASSOC_SHM;
 
-static FILE* open_maps(pid_t pid)
-{
-       return fopenf("r", "/proc/%d/maps", pid);
-}
+       f->map_start = start;
+       f->map_end = end;
+       f->pos = offset;
 
-static void free_maps(struct list_head *maps)
-{
-       list_free(maps, struct map, maps, free_map);
+       file_init_content(f);
 }
 
-static void collect_mem_files(struct proc *proc)
+static void collect_mem_files(struct path_cxt *pc, struct proc *proc)
 {
-
-       struct list_head maps;
        FILE *fp;
+       char buf[BUFSIZ];
 
-       INIT_LIST_HEAD(&maps);
-       fp = open_maps(proc->pid);
-       if (fp) {
-               read_maps(&maps, fp);
-               fclose(fp);
-       }
+       fp = ul_path_fopen(pc, "r", "maps");
+       if (!fp)
+               return;
 
-       collect_fd_files_generic(proc, "/proc/%d/map_files/", collect_mem_file, &maps);
+       while (fgets(buf, sizeof(buf), fp))
+               parse_maps_line(buf, proc);
 
-       free_maps(&maps);
+       fclose(fp);
 }
 
-
 static void collect_outofbox_files(struct path_cxt *pc,
                                   struct proc *proc,
                                   enum association assocs[],
@@ -893,7 +795,7 @@ static void read_process(struct lsfd_control *ctl, struct path_cxt *pc,
         */
        if (proc->pid == proc->leader->pid
            || kcmp(proc->leader->pid, proc->pid, KCMP_VM, 0, 0) != 0)
-               collect_mem_files(proc);
+               collect_mem_files(pc, proc);
 
        if (proc->pid == proc->leader->pid
            || kcmp(proc->leader->pid, proc->pid, KCMP_FILES, 0, 0) != 0)