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author | Hugh Dickins <hugh@veritas.com> | 2005-09-14 06:13:02 +0100 |
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committer | Linus Torvalds <torvalds@g5.osdl.org> | 2005-09-14 11:18:13 -0700 |
commit | 2fd4ef85e0db9ed75c98e13953257a967ea55e03 (patch) | |
tree | 119dfe9f88a832f3db6ff66e631112626f268f18 /fs | |
parent | fb085cf1d4294824571815d487daccc0609543f0 (diff) | |
download | linux-2fd4ef85e0db9ed75c98e13953257a967ea55e03.tar.gz linux-2fd4ef85e0db9ed75c98e13953257a967ea55e03.tar.bz2 linux-2fd4ef85e0db9ed75c98e13953257a967ea55e03.zip |
[PATCH] error path in setup_arg_pages() misses vm_unacct_memory()
Pavel Emelianov and Kirill Korotaev observe that fs and arch users of
security_vm_enough_memory tend to forget to vm_unacct_memory when a
failure occurs further down (typically in setup_arg_pages variants).
These are all users of insert_vm_struct, and that reservation will only
be unaccounted on exit if the vma is marked VM_ACCOUNT: which in some
cases it is (hidden inside VM_STACK_FLAGS) and in some cases it isn't.
So x86_64 32-bit and ppc64 vDSO ELFs have been leaking memory into
Committed_AS each time they're run. But don't add VM_ACCOUNT to them,
it's inappropriate to reserve against the very unlikely case that gdb
be used to COW a vDSO page - we ought to do something about that in
do_wp_page, but there are yet other inconsistencies to be resolved.
The safe and economical way to fix this is to let insert_vm_struct do
the security_vm_enough_memory check when it finds VM_ACCOUNT is set.
And the MIPS irix_brk has been calling security_vm_enough_memory before
calling do_brk which repeats it, doubly accounting and so also leaking.
Remove that, and all the fs and arch calls to security_vm_enough_memory:
give it a less misleading name later on.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-Off-By: Kirill Korotaev <dev@sw.ru>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/exec.c | 5 |
1 files changed, 0 insertions, 5 deletions
diff --git a/fs/exec.c b/fs/exec.c index 6fae59a22b43..a04a575ad433 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -421,11 +421,6 @@ int setup_arg_pages(struct linux_binprm *bprm, if (!mpnt) return -ENOMEM; - if (security_vm_enough_memory(arg_size >> PAGE_SHIFT)) { - kmem_cache_free(vm_area_cachep, mpnt); - return -ENOMEM; - } - memset(mpnt, 0, sizeof(*mpnt)); down_write(&mm->mmap_sem); |