From 8e96e3b7b8407be794ab1fd8e4b332818a358e78 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Sat, 3 Mar 2012 21:17:15 -0800 Subject: userns: Use uid_eq gid_eq helpers when comparing kuids and kgids in the vfs Acked-by: Serge Hallyn Signed-off-by: Eric W. Biederman --- fs/exec.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'fs/exec.c') diff --git a/fs/exec.c b/fs/exec.c index 9a1d9f0a60a..00ae2ef100d 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1139,7 +1139,7 @@ void setup_new_exec(struct linux_binprm * bprm) /* This is the point of no return */ current->sas_ss_sp = current->sas_ss_size = 0; - if (current_euid() == current_uid() && current_egid() == current_gid()) + if (uid_eq(current_euid(), current_uid()) && gid_eq(current_egid(), current_gid())) set_dumpable(current->mm, 1); else set_dumpable(current->mm, suid_dumpable); @@ -1153,8 +1153,8 @@ void setup_new_exec(struct linux_binprm * bprm) current->mm->task_size = TASK_SIZE; /* install the new credentials */ - if (bprm->cred->uid != current_euid() || - bprm->cred->gid != current_egid()) { + if (!uid_eq(bprm->cred->uid, current_euid()) || + !gid_eq(bprm->cred->gid, current_egid())) { current->pdeath_signal = 0; } else { would_dump(bprm, bprm->file); @@ -2120,7 +2120,7 @@ void do_coredump(long signr, int exit_code, struct pt_regs *regs) if (__get_dumpable(cprm.mm_flags) == 2) { /* Setuid core dump mode */ flag = O_EXCL; /* Stop rewrite attacks */ - cred->fsuid = 0; /* Dump root private */ + cred->fsuid = GLOBAL_ROOT_UID; /* Dump root private */ } retval = coredump_wait(exit_code, &core_state); @@ -2221,7 +2221,7 @@ void do_coredump(long signr, int exit_code, struct pt_regs *regs) * Dont allow local users get cute and trick others to coredump * into their pre-created files. */ - if (inode->i_uid != current_fsuid()) + if (!uid_eq(inode->i_uid, current_fsuid())) goto close_fail; if (!cprm.file->f_op || !cprm.file->f_op->write) goto close_fail; -- cgit v1.2.3 From 9e4a36ece652908276bc4abb4324ec56292453e1 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Wed, 16 Nov 2011 23:37:59 -0800 Subject: userns: Fail exec for suid and sgid binaries with ids outside our user namespace. Acked-by: Serge Hallyn Signed-off-by: Eric W. Biederman --- fs/exec.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'fs/exec.c') diff --git a/fs/exec.c b/fs/exec.c index 00ae2ef100d..e001bdfac53 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1291,8 +1291,11 @@ int prepare_binprm(struct linux_binprm *bprm) if (!(bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)) { /* Set-uid? */ if (mode & S_ISUID) { + if (!kuid_has_mapping(bprm->cred->user_ns, inode->i_uid)) + return -EPERM; bprm->per_clear |= PER_CLEAR_ON_SETID; bprm->cred->euid = inode->i_uid; + } /* Set-gid? */ @@ -1302,6 +1305,8 @@ int prepare_binprm(struct linux_binprm *bprm) * executable. */ if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) { + if (!kgid_has_mapping(bprm->cred->user_ns, inode->i_gid)) + return -EPERM; bprm->per_clear |= PER_CLEAR_ON_SETID; bprm->cred->egid = inode->i_gid; } -- cgit v1.2.3