diff options
Diffstat (limited to 'src/mman/shm_open.c')
| -rw-r--r-- | src/mman/shm_open.c | 37 |
1 files changed, 28 insertions, 9 deletions
diff --git a/src/mman/shm_open.c b/src/mman/shm_open.c index d368622d..a9be899b 100644 --- a/src/mman/shm_open.c +++ b/src/mman/shm_open.c @@ -3,19 +3,38 @@ #include <fcntl.h> #include <unistd.h> #include <string.h> +#include <limits.h> -int shm_open(const char *name, int flag, mode_t mode) -{ - int fd, dir; +char *__strchrnul(const char *, int); +static const char *mapname(const char *name, char *buf) +{ + char *p; while (*name == '/') name++; - if (strchr(name, '/')) { + if (*(p = __strchrnul(name, '/')) || p==name || + (p-name <= 2 && name[0]=='.' && p[-1]=='.')) { errno = EINVAL; - return -1; + return 0; } + if (p-name > NAME_MAX) { + errno = ENAMETOOLONG; + return 0; + } + memcpy(buf, "/dev/shm/", 9); + memcpy(buf+9, name, p-name+1); + return buf; +} - if ((dir = open("/dev/shm", O_DIRECTORY|O_RDONLY)) < 0) return -1; - fd = openat(dir, name, flag|O_NOFOLLOW|O_CLOEXEC|O_NONBLOCK, mode); - close(dir); - return fd; +int shm_open(const char *name, int flag, mode_t mode) +{ + char buf[NAME_MAX+10]; + if (!(name = mapname(name, buf))) return -1; + return open(name, flag|O_NOFOLLOW|O_CLOEXEC|O_NONBLOCK, mode); +} + +int shm_unlink(const char *name) +{ + char buf[NAME_MAX+10]; + if (!(name = mapname(name, buf))) return -1; + return unlink(name); } |