[2.6.20.17 review 40/58] do not limit locked memory when RLIMIT_MEMLOCK is RLIM_INFINITY

Willy Tarreau
2007-08-22T09:04:32Z

[-- Attachment #1: 0040-do-not-limit-locked-memory-when-RLIMIT_MEMLOCK-is-RL.patch --]
[-- Type: text/plain, Size: 1217 bytes --]

Fix a bug in mm/mlock.c on 32-bit architectures that prevents a user from
locking more than 4GB of shared memory, or allocating more than 4GB of
shared memory in hugepages, when rlim[RLIMIT_MEMLOCK] is set to
RLIM_INFINITY.

Signed-off-by: Herbert van den Bergh <herbert.van.den.bergh@oracle.com>
Acked-by: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Willy Tarreau <w@1wt.eu>
---
mm/mlock.c | 5 ++++-
1 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/mm/mlock.c b/mm/mlock.c
index 3446b7e..ef8fc94 100644
--- a/mm/mlock.c
+++ b/mm/mlock.c
@@ -233,9 +233,12 @@ int user_shm_lock(size_t size, struct user_struct *user)

locked = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur;
+ if (lock_limit == RLIM_INFINITY)
+ allowed = 1;
lock_limit >>= PAGE_SHIFT;
spin_lock(&shmlock_user_lock);
- if (locked + user->locked_shm > lock_limit && !capable(CAP_IPC_LOCK))
+ if (!allowed &&
+ locked + user->locked_shm > lock_limit && !capable(CAP_IPC_LOCK))
goto out;
get_uid(user);
user->locked_shm += locked;
--
1.5.2.5

--