5 files changed, 87 insertions, 31 deletions

diff --git a/fs/proc/Kconfig b/fs/proc/Kconfig
index 50f8f0600f06..6a0068841d96 100644
--- a/fs/proc/Kconfig
+++ b/fs/proc/Kconfig
@@ -33,8 +33,8 @@ config PROC_KCORE
         depends on PROC_FS && MMU
 
 config PROC_VMCORE
-        bool "/proc/vmcore support (EXPERIMENTAL)"
-        depends on PROC_FS && CRASH_DUMP
+        bool "/proc/vmcore support"
+        depends on PROC_FS && CRASH_DUMP
         default y
         help
         Exports the dump image of crashed kernel in ELF format.
diff --git a/fs/proc/base.c b/fs/proc/base.c
index a1c43e7c8a7b..53dc8ad40ae6 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1023,28 +1023,47 @@ static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
         memset(buffer, 0, sizeof(buffer));
         if (count > sizeof(buffer) - 1)
                 count = sizeof(buffer) - 1;
-        if (copy_from_user(buffer, buf, count))
-                return -EFAULT;
+        if (copy_from_user(buffer, buf, count)) {
+                err = -EFAULT;
+                goto out;
+        }
 
         err = strict_strtol(strstrip(buffer), 0, &oom_adjust);
         if (err)
-                return -EINVAL;
+                goto out;
         if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) &&
-             oom_adjust != OOM_DISABLE)
-                return -EINVAL;
+             oom_adjust != OOM_DISABLE) {
+                err = -EINVAL;
+                goto out;
+        }
 
         task = get_proc_task(file->f_path.dentry->d_inode);
-        if (!task)
-                return -ESRCH;
+        if (!task) {
+                err = -ESRCH;
+                goto out;
+        }
+
+        task_lock(task);
+        if (!task->mm) {
+                err = -EINVAL;
+                goto err_task_lock;
+        }
+
         if (!lock_task_sighand(task, &flags)) {
-                put_task_struct(task);
-                return -ESRCH;
+                err = -ESRCH;
+                goto err_task_lock;
         }
 
         if (oom_adjust < task->signal->oom_adj && !capable(CAP_SYS_RESOURCE)) {
-                unlock_task_sighand(task, &flags);
-                put_task_struct(task);
-                return -EACCES;
+                err = -EACCES;
+                goto err_sighand;
+        }
+
+        if (oom_adjust != task->signal->oom_adj) {
+                if (oom_adjust == OOM_DISABLE)
+                        atomic_inc(&task->mm->oom_disable_count);
+                if (task->signal->oom_adj == OOM_DISABLE)
+                        atomic_dec(&task->mm->oom_disable_count);
         }
 
         /*
@@ -1065,10 +1084,13 @@ static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
         else
                 task->signal->oom_score_adj = (oom_adjust * OOM_SCORE_ADJ_MAX) /
                                                                 -OOM_DISABLE;
+err_sighand:
         unlock_task_sighand(task, &flags);
+err_task_lock:
+        task_unlock(task);
         put_task_struct(task);
-
-        return count;
+out:
+        return err < 0 ? err : count;
 }
 
 static const struct file_operations proc_oom_adjust_operations = {
@@ -1109,30 +1131,49 @@ static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
         memset(buffer, 0, sizeof(buffer));
         if (count > sizeof(buffer) - 1)
                 count = sizeof(buffer) - 1;
-        if (copy_from_user(buffer, buf, count))
-                return -EFAULT;
+        if (copy_from_user(buffer, buf, count)) {
+                err = -EFAULT;
+                goto out;
+        }
 
         err = strict_strtol(strstrip(buffer), 0, &oom_score_adj);
         if (err)
-                return -EINVAL;
+                goto out;
         if (oom_score_adj < OOM_SCORE_ADJ_MIN ||
-                        oom_score_adj > OOM_SCORE_ADJ_MAX)
-                return -EINVAL;
+                        oom_score_adj > OOM_SCORE_ADJ_MAX) {
+                err = -EINVAL;
+                goto out;
+        }
 
         task = get_proc_task(file->f_path.dentry->d_inode);
-        if (!task)
-                return -ESRCH;
+        if (!task) {
+                err = -ESRCH;
+                goto out;
+        }
+
+        task_lock(task);
+        if (!task->mm) {
+                err = -EINVAL;
+                goto err_task_lock;
+        }
+
         if (!lock_task_sighand(task, &flags)) {
-                put_task_struct(task);
-                return -ESRCH;
+                err = -ESRCH;
+                goto err_task_lock;
         }
+
         if (oom_score_adj < task->signal->oom_score_adj &&
                         !capable(CAP_SYS_RESOURCE)) {
-                unlock_task_sighand(task, &flags);
-                put_task_struct(task);
-                return -EACCES;
+                err = -EACCES;
+                goto err_sighand;
         }
 
+        if (oom_score_adj != task->signal->oom_score_adj) {
+                if (oom_score_adj == OOM_SCORE_ADJ_MIN)
+                        atomic_inc(&task->mm->oom_disable_count);
+                if (task->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
+                        atomic_dec(&task->mm->oom_disable_count);
+        }
         task->signal->oom_score_adj = oom_score_adj;
         /*
          * Scale /proc/pid/oom_adj appropriately ensuring that OOM_DISABLE is
@@ -1143,14 +1184,19 @@ static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
         else
                 task->signal->oom_adj = (oom_score_adj * OOM_ADJUST_MAX) /
                                                         OOM_SCORE_ADJ_MAX;
+err_sighand:
         unlock_task_sighand(task, &flags);
+err_task_lock:
+        task_unlock(task);
         put_task_struct(task);
-        return count;
+out:
+        return err < 0 ? err : count;
 }
 
 static const struct file_operations proc_oom_score_adj_operations = {
         .read           = oom_score_adj_read,
         .write          = oom_score_adj_write,
+        .llseek         = default_llseek,
 };
 
 #ifdef CONFIG_AUDITSYSCALL
@@ -2039,11 +2085,13 @@ static ssize_t proc_fdinfo_read(struct file *file, char __user *buf,
 static const struct file_operations proc_fdinfo_file_operations = {
         .open           = nonseekable_open,
         .read           = proc_fdinfo_read,
+        .llseek         = no_llseek,
 };
 
 static const struct file_operations proc_fd_operations = {
         .read           = generic_read_dir,
         .readdir        = proc_readfd,
+        .llseek         = default_llseek,
 };
 
 /*
@@ -2112,6 +2160,7 @@ static int proc_readfdinfo(struct file *filp, void *dirent, filldir_t filldir)
 static const struct file_operations proc_fdinfo_operations = {
         .read           = generic_read_dir,
         .readdir        = proc_readfdinfo,
+        .llseek         = default_llseek,
 };
 
 /*
@@ -2343,6 +2392,7 @@ static int proc_attr_dir_readdir(struct file * filp,
 static const struct file_operations proc_attr_dir_operations = {
         .read           = generic_read_dir,
         .readdir        = proc_attr_dir_readdir,
+        .llseek         = default_llseek,
 };
 
 static struct dentry *proc_attr_dir_lookup(struct inode *dir,
@@ -2675,7 +2725,7 @@ static const struct pid_entry tgid_base_stuff[] = {
         INF("auxv",       S_IRUSR, proc_pid_auxv),
         ONE("status",     S_IRUGO, proc_pid_status),
         ONE("personality", S_IRUSR, proc_pid_personality),
-        INF("limits",     S_IRUSR, proc_pid_limits),
+        INF("limits",     S_IRUGO, proc_pid_limits),
 #ifdef CONFIG_SCHED_DEBUG
         REG("sched",      S_IRUGO|S_IWUSR, proc_pid_sched_operations),
 #endif
@@ -2751,6 +2801,7 @@ static int proc_tgid_base_readdir(struct file * filp,
 static const struct file_operations proc_tgid_base_operations = {
         .read           = generic_read_dir,
         .readdir        = proc_tgid_base_readdir,
+        .llseek         = default_llseek,
 };
 
 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
@@ -3011,7 +3062,7 @@ static const struct pid_entry tid_base_stuff[] = {
         INF("auxv",      S_IRUSR, proc_pid_auxv),
         ONE("status",    S_IRUGO, proc_pid_status),
         ONE("personality", S_IRUSR, proc_pid_personality),
-        INF("limits",    S_IRUSR, proc_pid_limits),
+        INF("limits",    S_IRUGO, proc_pid_limits),
 #ifdef CONFIG_SCHED_DEBUG
         REG("sched",     S_IRUGO|S_IWUSR, proc_pid_sched_operations),
 #endif
@@ -3088,6 +3139,7 @@ static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *den
 static const struct file_operations proc_tid_base_operations = {
         .read           = generic_read_dir,
         .readdir        = proc_tid_base_readdir,
+        .llseek         = default_llseek,
 };
 
 static const struct inode_operations proc_tid_base_inode_operations = {
@@ -3324,4 +3376,5 @@ static const struct inode_operations proc_task_inode_operations = {
 static const struct file_operations proc_task_operations = {
         .read           = generic_read_dir,
         .readdir        = proc_task_readdir,
+        .llseek         = default_llseek,
 };
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index 5be436ea088e..2fc52552271d 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -364,6 +364,7 @@ static int proc_sys_getattr(struct vfsmount *mnt, struct dentry *dentry, struct
 static const struct file_operations proc_sys_file_operations = {
         .read           = proc_sys_read,
         .write          = proc_sys_write,
+        .llseek         = default_llseek,
 };
 
 static const struct file_operations proc_sys_dir_file_operations = {
diff --git a/fs/proc/root.c b/fs/proc/root.c
index 4258384ed22d..93d99b316325 100644
--- a/fs/proc/root.c
+++ b/fs/proc/root.c
@@ -179,6 +179,7 @@ static int proc_root_readdir(struct file * filp,
 static const struct file_operations proc_root_operations = {
         .read            = generic_read_dir,
         .readdir         = proc_root_readdir,
+        .llseek         = default_llseek,
 };
 
 /*
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 1dbca4e8cc16..871e25ed0069 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -539,6 +539,7 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf,
 
 const struct file_operations proc_clear_refs_operations = {
         .write          = clear_refs_write,
+        .llseek         = noop_llseek,
 };
 
 struct pagemapread {