mirror of
https://github.com/torvalds/linux
synced 2024-11-05 18:23:50 +00:00
[PATCH] xacct_add_tsk: fix pure theoretical ->mm use-after-free
Paranoid fix. The task can free its ->mm after the 'if (p->mm)' check. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Shailabh Nagar <nagar@watson.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Jay Lan <jlan@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
parent
d45e44d4be
commit
f0ec1aaf54
1 changed files with 7 additions and 3 deletions
|
@ -80,13 +80,17 @@ void bacct_add_tsk(struct taskstats *stats, struct task_struct *tsk)
|
|||
*/
|
||||
void xacct_add_tsk(struct taskstats *stats, struct task_struct *p)
|
||||
{
|
||||
struct mm_struct *mm;
|
||||
|
||||
/* convert pages-jiffies to Mbyte-usec */
|
||||
stats->coremem = jiffies_to_usecs(p->acct_rss_mem1) * PAGE_SIZE / MB;
|
||||
stats->virtmem = jiffies_to_usecs(p->acct_vm_mem1) * PAGE_SIZE / MB;
|
||||
if (p->mm) {
|
||||
mm = get_task_mm(p);
|
||||
if (mm) {
|
||||
/* adjust to KB unit */
|
||||
stats->hiwater_rss = p->mm->hiwater_rss * PAGE_SIZE / KB;
|
||||
stats->hiwater_vm = p->mm->hiwater_vm * PAGE_SIZE / KB;
|
||||
stats->hiwater_rss = mm->hiwater_rss * PAGE_SIZE / KB;
|
||||
stats->hiwater_vm = mm->hiwater_vm * PAGE_SIZE / KB;
|
||||
mmput(mm);
|
||||
}
|
||||
stats->read_char = p->rchar;
|
||||
stats->write_char = p->wchar;
|
||||
|
|
Loading…
Reference in a new issue