diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c index 64b5b4fbb1..b3d0674f6d 100644 --- a/tools/virtiofsd/passthrough_ll.c +++ b/tools/virtiofsd/passthrough_ll.c @@ -54,6 +54,7 @@ #include #include #include +#include #include "qemu/cutils.h" #include "passthrough_helpers.h" @@ -1161,6 +1162,30 @@ static void lo_lookup(fuse_req_t req, fuse_ino_t parent, const char *name) #define OURSYS_setresuid SYS_setresuid #endif +static void drop_supplementary_groups(void) +{ + int ret; + + ret = getgroups(0, NULL); + if (ret == -1) { + fuse_log(FUSE_LOG_ERR, "getgroups() failed with error=%d:%s\n", + errno, strerror(errno)); + exit(1); + } + + if (!ret) { + return; + } + + /* Drop all supplementary groups. We should not need it */ + ret = setgroups(0, NULL); + if (ret == -1) { + fuse_log(FUSE_LOG_ERR, "setgroups() failed with error=%d:%s\n", + errno, strerror(errno)); + exit(1); + } +} + /* * Change to uid/gid of caller so that file is created with * ownership of caller. @@ -3926,6 +3951,8 @@ int main(int argc, char *argv[]) qemu_init_exec_dir(argv[0]); + drop_supplementary_groups(); + pthread_mutex_init(&lo.mutex, NULL); lo.inodes = g_hash_table_new(lo_key_hash, lo_key_equal); lo.root.fd = -1;