diff options
| author | Andrew Morton <akpm@digeo.com> | 2003-02-10 07:37:12 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@home.transmeta.com> | 2003-02-10 07:37:12 -0800 |
| commit | b789ebfca657a1fc77f6bd4dd648c0d5e96057c8 (patch) | |
| tree | 96074583f732c733a6a62eabe48ca7f35203be98 /kernel/user.c | |
| parent | 3322be329b2b75c784e0614aee71adc0dff2afdc (diff) | |
[PATCH] fix current->user->processes leak
Patch from: Eric Lammerts <eric@lammerts.org>
Every time you do a loop mount, a kernel thread is started (those
processes are called "loop0", "loop1", etc.). The problem is that when
it starts, it's counted as one of your processes. Then, it's
changed to be a root-owned process without correcting that count.
Patch below fixes the problem. It moves the bookkeeping of changing
current->user to a new function switch_uid() (which is now also used
by exec_usermodehelper() in kmod.c). The patch is tested.
Diffstat (limited to 'kernel/user.c')
| -rw-r--r-- | kernel/user.c | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/kernel/user.c b/kernel/user.c index 0704b2aad9c5..592680d8cc68 100644 --- a/kernel/user.c +++ b/kernel/user.c @@ -116,6 +116,23 @@ struct user_struct * alloc_uid(uid_t uid) return up; } +void switch_uid(struct user_struct *new_user) +{ + struct user_struct *old_user; + + /* What if a process setreuid()'s and this brings the + * new uid over his NPROC rlimit? We can check this now + * cheaply with the new uid cache, so if it matters + * we should be checking for it. -DaveM + */ + old_user = current->user; + atomic_inc(&new_user->__count); + atomic_inc(&new_user->processes); + atomic_dec(&old_user->processes); + current->user = new_user; + free_uid(old_user); +} + static int __init uid_cache_init(void) { |