diff options
Diffstat (limited to 'security/selinux/hooks.c')
| -rw-r--r-- | security/selinux/hooks.c | 33 |
1 files changed, 25 insertions, 8 deletions
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index d5d67c93b65c..869c2f1e0da1 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -233,6 +233,14 @@ static int inode_alloc_security(struct inode *inode) return 0; } +static void inode_free_rcu(struct rcu_head *head) +{ + struct inode_security_struct *isec; + + isec = container_of(head, struct inode_security_struct, rcu); + kmem_cache_free(sel_inode_cache, isec); +} + static void inode_free_security(struct inode *inode) { struct inode_security_struct *isec = inode->i_security; @@ -243,8 +251,16 @@ static void inode_free_security(struct inode *inode) list_del_init(&isec->list); spin_unlock(&sbsec->isec_lock); - inode->i_security = NULL; - kmem_cache_free(sel_inode_cache, isec); + /* + * The inode may still be referenced in a path walk and + * a call to selinux_inode_permission() can be made + * after inode_free_security() is called. Ideally, the VFS + * wouldn't do this, but fixing that is a much harder + * job. For now, simply free the i_security via RCU, and + * leave the current inode->i_security pointer intact. + * The inode will be freed after the RCU grace period too. + */ + call_rcu(&isec->rcu, inode_free_rcu); } static int file_alloc_security(struct file *file) @@ -652,7 +668,7 @@ static int selinux_set_mnt_opts(struct super_block *sb, if (flags[i] == SBLABEL_MNT) continue; rc = security_context_to_sid(mount_options[i], - strlen(mount_options[i]), &sid); + strlen(mount_options[i]), &sid, GFP_KERNEL); if (rc) { printk(KERN_WARNING "SELinux: security_context_to_sid" "(%s) failed for (dev %s, type %s) errno=%d\n", @@ -2491,7 +2507,8 @@ static int selinux_sb_remount(struct super_block *sb, void *data) if (flags[i] == SBLABEL_MNT) continue; len = strlen(mount_options[i]); - rc = security_context_to_sid(mount_options[i], len, &sid); + rc = security_context_to_sid(mount_options[i], len, &sid, + GFP_KERNEL); if (rc) { printk(KERN_WARNING "SELinux: security_context_to_sid" "(%s) failed for (dev %s, type %s) errno=%d\n", @@ -2895,7 +2912,7 @@ static int selinux_inode_setxattr(struct dentry *dentry, const char *name, if (rc) return rc; - rc = security_context_to_sid(value, size, &newsid); + rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL); if (rc == -EINVAL) { if (!capable(CAP_MAC_ADMIN)) { struct audit_buffer *ab; @@ -3052,7 +3069,7 @@ static int selinux_inode_setsecurity(struct inode *inode, const char *name, if (!value || !size) return -EACCES; - rc = security_context_to_sid((void *)value, size, &newsid); + rc = security_context_to_sid((void *)value, size, &newsid, GFP_KERNEL); if (rc) return rc; @@ -5527,7 +5544,7 @@ static int selinux_setprocattr(struct task_struct *p, str[size-1] = 0; size--; } - error = security_context_to_sid(value, size, &sid); + error = security_context_to_sid(value, size, &sid, GFP_KERNEL); if (error == -EINVAL && !strcmp(name, "fscreate")) { if (!capable(CAP_MAC_ADMIN)) { struct audit_buffer *ab; @@ -5636,7 +5653,7 @@ static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) { - return security_context_to_sid(secdata, seclen, secid); + return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL); } static void selinux_release_secctx(char *secdata, u32 seclen) |