mirror of https://gitee.com/openkylin/linux.git
2fd4ef85e0
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> |
||
|---|---|---|
| .. | ||
| Makefile | ||
| binfmt_elf32.c | ||
| elfcore32.h | ||
| ia32_entry.S | ||
| ia32_ioctl.c | ||
| ia32_ldt.c | ||
| ia32_signal.c | ||
| ia32_support.c | ||
| ia32_traps.c | ||
| ia32priv.h | ||
| sys_ia32.c | ||