Re: 2.6.12-rc4-mm2 - sleeping function called from invalid context at mm/slab.c:2502

From: Chris Wright
Date: Fri May 20 2005 - 12:06:15 EST


* Stephen Smalley (sds@xxxxxxxxxxxxx) wrote:
> Untested patch below, relative to 2.6.12-rc4-mm2 plus your socketcall
> patch to avoid the obvious conflict there. Is this what you had in
> mind?
>
> include/linux/audit.h | 2 ++
> kernel/auditsc.c | 38 ++++++++++++++++++++++++++++++++++++++
> security/selinux/avc.c | 17 ++++++++---------
> 3 files changed, 48 insertions(+), 9 deletions(-)
>
> --- linux-2.6.12-rc4-mm2/include/linux/audit.h.orig 2005-05-20 12:37:41.000000000 -0400
> +++ linux-2.6.12-rc4-mm2/include/linux/audit.h 2005-05-20 12:38:15.000000000 -0400
> @@ -238,6 +238,7 @@ extern uid_t audit_get_loginuid(struct a
> extern int audit_ipc_perms(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode);
> extern int audit_socketcall(int nargs, unsigned long *args);
> extern int audit_sockaddr(int len, void *addr);
> +extern int audit_avc_path(struct dentry *dentry, struct vfsmount *mnt);
> extern void audit_signal_info(int sig, struct task_struct *t);
> #else
> #define audit_alloc(t) ({ 0; })
> @@ -253,6 +254,7 @@ extern void audit_signal_info(int sig, s
> #define audit_ipc_perms(q,u,g,m) ({ 0; })
> #define audit_socketcall(n,a) ({ 0; })
> #define audit_sockaddr(len, addr) ({ 0; })
> +#define audit_avc_path(dentry, mnt) ({ 0; })
> #define audit_signal_info(s,t) do { ; } while (0)
> #endif
>
> --- linux-2.6.12-rc4-mm2/kernel/auditsc.c.orig 2005-05-20 12:37:19.000000000 -0400
> +++ linux-2.6.12-rc4-mm2/kernel/auditsc.c 2005-05-20 12:43:05.000000000 -0400
> @@ -34,6 +34,7 @@
> #include <asm/types.h>
> #include <linux/mm.h>
> #include <linux/module.h>
> +#include <linux/mount.h>
> #include <linux/socket.h>
> #include <linux/audit.h>
> #include <linux/personality.h>
> @@ -124,6 +125,11 @@ struct audit_aux_data_sockaddr {
> char a[0];
> };
>
> +struct audit_aux_data_avc {

I guess it's not really avc specific (although it's primary user).

> + struct audit_aux_data d;
> + struct dentry *dentry;
> + struct vfsmount *mnt;
> +};
>
> /* The per-task audit context. */
> struct audit_context {
> @@ -553,6 +559,11 @@ static inline void audit_free_aux(struct
> struct audit_aux_data *aux;
>
> while ((aux = context->aux)) {
> + if (aux->type == AUDIT_AVC) {
> + struct audit_aux_data_avc *axi = (void *)aux;
> + dput(axi->dentry);
> + mntput(axi->mnt);
> + }
> context->aux = aux->next;
> kfree(aux);
> }
> @@ -728,6 +739,12 @@ static void audit_log_exit(struct audit_
> } /* case AUDIT_SOCKADDR */
> break;
>
> + case AUDIT_AVC: {
> + struct audit_aux_data_avc *axi = (void *)aux;
> + if (axi->dentry)
> + audit_log_d_path(ab, "path=", axi->dentry, axi->mnt);
> + } /* case AUDIT_AVC */

Won't this change the order quite a bit? And how do you correlate path
vs. exe, etc.? Oh, I see, you're not using it for exe...

> + break;
> }
> audit_log_end(ab);
>
> @@ -1128,6 +1145,27 @@ int audit_sockaddr(int len, void *a)
> return 0;
> }
>
> +int audit_avc_path(struct dentry *dentry, struct vfsmount *mnt)
> +{
> + struct audit_aux_data_avc *ax;
> + struct audit_context *context = current->audit_context;
> +
> + if (likely(!context))
> + return 0;
> +
> + ax = kmalloc(sizeof(*ax), GFP_ATOMIC);
> + if (!ax)
> + return -ENOMEM;
> +
> + ax->dentry = dget(dentry);
> + ax->mnt = mntget(mnt);
> +
> + ax->d.type = AUDIT_AVC;
> + ax->d.next = context->aux;
> + context->aux = (void *)ax;
> + return 0;
> +}
> +
> void audit_signal_info(int sig, struct task_struct *t)
> {
> extern pid_t audit_sig_pid;
> --- linux-2.6.12-rc4-mm2/security/selinux/avc.c.orig 2005-05-20 12:37:41.000000000 -0400
> +++ linux-2.6.12-rc4-mm2/security/selinux/avc.c 2005-05-20 12:39:06.000000000 -0400
> @@ -566,13 +566,10 @@ void avc_audit(u32 ssid, u32 tsid,
> case AVC_AUDIT_DATA_FS:
> if (a->u.fs.dentry) {
> struct dentry *dentry = a->u.fs.dentry;
> - if (a->u.fs.mnt) {
> - audit_log_d_path(ab, "path=", dentry,
> - a->u.fs.mnt);
> - } else {
> - audit_log_format(ab, " name=%s",
> - dentry->d_name.name);
> - }
> + if (a->u.fs.mnt)
> + audit_avc_path(dentry, a->u.fs.mnt);
> + audit_log_format(ab, " name=%s",
> + dentry->d_name.name);
> inode = dentry->d_inode;
> } else if (a->u.fs.inode) {
> struct dentry *dentry;
> @@ -623,8 +620,10 @@ void avc_audit(u32 ssid, u32 tsid,
> case AF_UNIX:
> u = unix_sk(sk);
> if (u->dentry) {
> - audit_log_d_path(ab, "path=",
> - u->dentry, u->mnt);
> + audit_avc_path(u->dentry, u->mnt);
> + audit_log_format(ab, " name=%s",
> + u->dentry->d_name.name);
> +
> break;
> }
> if (!u->addr)
>
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/