Re: [PATCH] IPC_SET_PERM cleanup

The following patch addresses most of the issues with the IPC_SET_PERM records as described in: https://www.redhat.com/archives/linux-audit/2006-May/msg00010.html

To summarize, I made the following changes: 1. Changed sys_msgctl() and semctl_down() so that an IPC_SET_PERM record is emitted in the failure case as well as the success case. This matches the behavior in sys_shmctl(). I could simplify the code in sys_msgctl() and semctl_down() slightly but it would mean that in some error cases we could get an IPC_SET_PERM record without an IPC record and that seemed odd. 2. No change to the IPC record type, given no feedback on the backward compatibility question. 3. Removed the qbytes field from the IPC record. It wasn't being set and when audit_ipc_obj() is called from ipcperms(), the information isn't available. If we want the information in the IPC record, more extensive changes will be necessary. Since it only applies to message queues and it isn't really permission related, it doesn't seem worth it. 4. Removed the obj field from the IPC_SET_PERM record. This means that the kern_ipc_perm argument is no longer needed. 5. Replaced the spaces in the IPC_SET_PERM field names with underscores.

I tested this with the lspp.22 kernel on an x86_64 box. Please let me know if you see any issues. -- ljk include/linux/audit.h | 2 +- ipc/msg.c | 9 +++++---- ipc/sem.c | 8 +++++--- ipc/shm.c | 2 +- kernel/auditsc.c | 22 +++++----------------- 5 files changed, 17 insertions(+), 26 deletions(-) --- linux-2.6.16.x86_64.orig/kernel/auditsc.c 2006-05-05 14:29:42.000000000 -0400 +++ linux-2.6.16.x86_64/kernel/auditsc.c 2006-05-05 14:48:44.000000000 -0400 @@ -665,8 +665,8 @@ static void audit_log_exit(struct audit_ case AUDIT_IPC: { struct audit_aux_data_ipcctl *axi = (void *)aux; audit_log_format(ab, - " qbytes=%lx iuid=%u igid=%u mode=%x", - axi->qbytes, axi->uid, axi->gid, axi->mode); + "iuid=%u igid=%u mode=%x", + axi->uid, axi->gid, axi->mode); if (axi->osid != 0) { char *ctx = NULL; u32 len; @@ -684,21 +684,10 @@ static void audit_log_exit(struct audit_ case AUDIT_IPC_SET_PERM: { struct audit_aux_data_ipcctl *axi = (void *)aux; audit_log_format(ab, - " new qbytes=%lx new iuid=%u new igid=%u new mode=%x", + "new_qbytes=%lx new_iuid=%u new_igid=%u new_mode=%x", axi->qbytes, axi->uid, axi->gid, axi->mode); - if (axi->osid != 0) { - char *ctx = NULL; - u32 len; - if (selinux_ctxid_to_string( - axi->osid, &ctx, &len)) { - audit_log_format(ab, " osid=%u", - axi->osid); - call_panic = 1; - } else - audit_log_format(ab, " obj=%s", ctx); - kfree(ctx); - } break; } + case AUDIT_EXECVE: { struct audit_aux_data_execve *axi = (void *)aux; int i; @@ -1232,7 +1221,7 @@ int audit_ipc_obj(struct kern_ipc_perm * * * Returns 0 for success or NULL context or < 0 on error. */ -int audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode, struct kern_ipc_perm *ipcp) +int audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode) { struct audit_aux_data_ipcctl *ax; struct audit_context *context = current->audit_context; @@ -1248,7 +1237,6 @@ int audit_ipc_set_perm(unsigned long qby ax->uid = uid; ax->gid = gid; ax->mode = mode; - selinux_get_ipc_sid(ipcp, &ax->osid); ax->d.type = AUDIT_IPC_SET_PERM; ax->d.next = context->aux; --- linux-2.6.16.x86_64.orig/ipc/msg.c 2006-05-05 14:30:15.000000000 -0400 +++ linux-2.6.16.x86_64/ipc/msg.c 2006-05-05 14:50:32.000000000 -0400 @@ -454,6 +454,11 @@ asmlinkage long sys_msgctl (int msqid, i err = audit_ipc_obj(ipcp); if (err) goto out_unlock_up; + if (cmd==IPC_SET) { + err = audit_ipc_set_perm(setbuf.qbytes, setbuf.uid, setbuf.gid, setbuf.mode); + if (err) + goto out_unlock_up; + } err = -EPERM; if (current->euid != ipcp->cuid && @@ -468,10 +473,6 @@ asmlinkage long sys_msgctl (int msqid, i switch (cmd) { case IPC_SET: { - err = audit_ipc_set_perm(setbuf.qbytes, setbuf.uid, setbuf.gid, setbuf.mode, ipcp); - if (err) - goto out_unlock_up; - err = -EPERM; if (setbuf.qbytes > msg_ctlmnb && !capable(CAP_SYS_RESOURCE)) goto out_unlock_up; --- linux-2.6.16.x86_64.orig/ipc/shm.c 2006-05-05 15:08:23.000000000 -0400 +++ linux-2.6.16.x86_64/ipc/shm.c 2006-05-05 14:51:53.000000000 -0400 @@ -643,7 +643,7 @@ asmlinkage long sys_shmctl (int shmid, i err = audit_ipc_obj(&(shp->shm_perm)); if (err) goto out_unlock_up; - err = audit_ipc_set_perm(0, setbuf.uid, setbuf.gid, setbuf.mode, &(shp->shm_perm)); + err = audit_ipc_set_perm(0, setbuf.uid, setbuf.gid, setbuf.mode); if (err) goto out_unlock_up; err=-EPERM; --- linux-2.6.16.x86_64.orig/ipc/sem.c 2006-05-05 14:30:02.000000000 -0400 +++ linux-2.6.16.x86_64/ipc/sem.c 2006-05-05 14:50:58.000000000 -0400 @@ -828,6 +828,11 @@ static int semctl_down(int semid, int se if (err) goto out_unlock; + if (cmd == IPC_SET) { + err = audit_ipc_set_perm(0, setbuf.uid, setbuf.gid, setbuf.mode); + if (err) + goto out_unlock; + } if (current->euid != ipcp->cuid && current->euid != ipcp->uid && !capable(CAP_SYS_ADMIN)) { err=-EPERM; @@ -844,9 +849,6 @@ static int semctl_down(int semid, int se err = 0; break; case IPC_SET: - err = audit_ipc_set_perm(0, setbuf.uid, setbuf.gid, setbuf.mode, ipcp); - if (err) - goto out_unlock; ipcp->uid = setbuf.uid; ipcp->gid = setbuf.gid; ipcp->mode = (ipcp->mode & ~S_IRWXUGO) --- linux-2.6.16.x86_64.orig/include/linux/audit.h 2006-05-05 15:09:42.000000000 -0400 +++ linux-2.6.16.x86_64/include/linux/audit.h 2006-05-05 14:49:35.000000000 -0400 @@ -324,7 +324,7 @@ extern void auditsc_get_stamp(struct aud extern int audit_set_loginuid(struct task_struct *task, uid_t loginuid); extern uid_t audit_get_loginuid(struct audit_context *ctx); extern int audit_ipc_obj(struct kern_ipc_perm *ipcp); -extern int audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode, struct kern_ipc_perm *ipcp); +extern int audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode); extern int audit_bprm(struct linux_binprm *bprm); extern int audit_socketcall(int nargs, unsigned long *args); extern int audit_sockaddr(int len, void *addr); -- Linux-audit mailing list Linux-audit(a)redhat.com https://www.redhat.com/mailman/listinfo/linux-audit