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bubblewrap-0.4.0_realpath-workaround.patch (1654B)

    

  1. https://git.alpinelinux.org/aports/plain/main/bubblewrap/realpath-workaround.patch
  3. Musl realpath() implementation currently depends on /proc which is
  4. not available when setting up pivot root. For the time being just
  5. fallback to a naive normalization algorithm originated from
  6. VoidLinux' xbps. If there was path that would have required advanced
  7. normalizing as provided by realpath() the following parse_mountinfo()
  8. will fail.
  11. diff --git bind-mount.c.orig bind-mount.c
  12. index 045fa0e..d05b540 100644
  13. --- ./bind-mount.c.orig
  14. +++ ./bind-mount.c
  15. @@ -23,6 +23,28 @@
  16.  #include "utils.h"
  17.  #include "bind-mount.h"
  18.  
  19. +#ifndef __GLIBC__
  20. +static char *
  21. +normpath(char *path)
  22. +{
  23. +  char *seg = NULL, *p = NULL;
  24. +
  25. +  for (p = path, seg = NULL; *p; p++) {
  26. +    if (strncmp(p, "/../", 4) == 0 || strncmp(p, "/..", 4) == 0) {
  27. +      memmove(seg ? seg : p, p+3, strlen(p+3) + 1);
  28. +      return normpath(path);
  29. +    } else if (strncmp(p, "/./", 3) == 0 || strncmp(p, "/.", 3) == 0) {
  30. +      memmove(p, p+2, strlen(p+2) + 1);
  31. +    } else if (strncmp(p, "//", 2) == 0 || strncmp(p, "/", 2) == 0) {
  32. +      memmove(p, p+1, strlen(p+1) + 1);
  33. +    }
  34. +    if (*p == '/')
  35. +      seg = p;
  36. +  }
  37. +  return path;
  38. +}
  39. +#endif
  40. +
  41.  static char *
  42.  skip_token (char *line, bool eat_whitespace)
  43.  {
  44. @@ -397,7 +419,11 @@ bind_mount (int           proc_fd,
  45.       path, so to find it in the mount table we need to do that too. */
  46.    resolved_dest = realpath (dest, NULL);
  47.    if (resolved_dest == NULL)
  48. +#ifdef __GLIBC__
  49.      return 2;
  50. +#else
  51. +    resolved_dest = normpath(strdup(dest));
  52. +#endif
  53.  
  54.    mount_tab = parse_mountinfo (proc_fd, resolved_dest);
  55.    if (mount_tab[0].mountpoint == NULL)