Switch setuid() to lookup fsids in the fsid mappings. If no fsid mappings are setup the behavior is unchanged, i.e. fsids are looked up in the id mappings. Signed-off-by: Christian Brauner <christian.brauner@xxxxxxxxxx> --- kernel/sys.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/kernel/sys.c b/kernel/sys.c index b89334ad0908..afaec8d46bc5 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -574,11 +574,16 @@ long __sys_setuid(uid_t uid) struct cred *new; int retval; kuid_t kuid; + kuid_t kfsuid; kuid = make_kuid(ns, uid); if (!uid_valid(kuid)) return -EINVAL; + kfsuid = make_kfsuid(ns, uid); + if (!uid_valid(kfsuid)) + return -EINVAL; + new = prepare_creds(); if (!new) return -ENOMEM; @@ -596,7 +601,8 @@ long __sys_setuid(uid_t uid) goto error; } - new->fsuid = new->euid = kuid; + new->euid = kuid; + new->fsuid = kfsuid; retval = security_task_fix_setuid(new, old, LSM_SETID_ID); if (retval < 0) -- 2.25.0
