diff options
| -rw-r--r-- | lib/libzpool/kernel.c | 40 |
1 files changed, 37 insertions, 3 deletions
diff --git a/lib/libzpool/kernel.c b/lib/libzpool/kernel.c index ed9c1a9ef..e67d13c92 100644 --- a/lib/libzpool/kernel.c +++ b/lib/libzpool/kernel.c @@ -1288,27 +1288,61 @@ umem_out_of_memory(void) return (0); } +#define HOSTID_MASK 0xffffffff + static unsigned long get_spl_hostid(void) { FILE *f; unsigned long hostid; + char *env; + + /* + * Allow the hostid to be subverted for testing. + */ + env = getenv("ZFS_HOSTID"); + if (env) { + hostid = strtoull(env, NULL, 0); + return (hostid & HOSTID_MASK); + } f = fopen("/sys/module/spl/parameters/spl_hostid", "r"); if (!f) return (0); + if (fscanf(f, "%lu", &hostid) != 1) hostid = 0; + fclose(f); - return (hostid & 0xffffffff); + + return (hostid & HOSTID_MASK); } unsigned long get_system_hostid(void) { unsigned long system_hostid = get_spl_hostid(); - if (system_hostid == 0) - system_hostid = gethostid() & 0xffffffff; + /* + * We do not use the library call gethostid() because + * it generates a hostid value that the kernel is + * unaware of, if the spl_hostid module parameter has not + * been set and there is no system hostid file (e.g. + * /etc/hostid). The kernel and userspace must agree. + * See comments above hostid_read() in the SPL. + */ + if (system_hostid == 0) { + int fd, rc; + unsigned long hostid; + int hostid_size = 4; /* 4 bytes regardless of arch */ + + fd = open("/etc/hostid", O_RDONLY); + if (fd >= 0) { + rc = read(fd, &hostid, hostid_size); + if (rc > 0) + system_hostid = (hostid & HOSTID_MASK); + close(fd); + } + } return (system_hostid); } |