From b610c04c667f3c056243fd64041c7f152a512ee4 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Mon, 30 Jul 2012 14:42:40 -0700 Subject: ipc: allow compat IPC version field parsing if !ARCH_WANT_OLD_COMPAT_IPC Commit 48b25c43e6ee ("ipc: provide generic compat versions of IPC syscalls") added a new ARCH_WANT_OLD_COMPAT_IPC config option for architectures to select if their compat target requires the old IPC syscall interface. For architectures (such as AArch64) that do not require the internal calling conventions provided by this option, but have a compat target where the C library passes the IPC_64 flag explicitly, compat_ipc_parse_version no longer strips out the flag before calling the native system call implementation, resulting in unknown SHM/IPC commands and -EINVAL being returned to userspace. This patch separates the selection of the internal calling conventions for the IPC syscalls from the version parsing, allowing architectures to select __ARCH_WANT_COMPAT_IPC_PARSE_VERSION if they want to use version parsing whilst retaining the newer syscall calling conventions. Acked-by: Chris Metcalf Cc: Arnd Bergmann Acked-by: Catalin Marinas Signed-off-by: Will Deacon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/compat.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/linux/compat.h') diff --git a/include/linux/compat.h b/include/linux/compat.h index 4e890394ef99..9f68e90a14ec 100644 --- a/include/linux/compat.h +++ b/include/linux/compat.h @@ -256,6 +256,7 @@ compat_sys_get_robust_list(int pid, compat_uptr_t __user *head_ptr, compat_size_t __user *len_ptr); #ifdef CONFIG_ARCH_WANT_OLD_COMPAT_IPC +#define __ARCH_WANT_COMPAT_IPC_PARSE_VERSION long compat_sys_semctl(int first, int second, int third, void __user *uptr); long compat_sys_msgsnd(int first, int second, int third, void __user *uptr); long compat_sys_msgrcv(int first, int second, int msgtyp, int third, -- cgit v1.2.3 From 05ba3f1aa1b04e921068249dd52a80bc84c2aeb4 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Mon, 30 Jul 2012 14:42:43 -0700 Subject: ipc: compat: use signed size_t types for msgsnd and msgrcv The msgsnd and msgrcv system calls use size_t to represent the size of the message being transferred. POSIX states that values of msgsz greater than SSIZE_MAX cause the result to be implementation-defined. On Linux, this equates to returning -EINVAL if (long) msgsz < 0. For compat tasks where !CONFIG_ARCH_WANT_OLD_COMPAT_IPC and compat_size_t is smaller than size_t, negative size values passed from userspace will be interpreted as positive values by do_msg{rcv,snd} and will fail to exit early with -EINVAL. This patch changes the compat prototypes for msg{rcv,snd} so that the message size is represented as a compat_ssize_t, which we cast to the native ssize_t type for the core IPC code. Cc: Arnd Bergmann Acked-by: Chris Metcalf Acked-by: Catalin Marinas Signed-off-by: Will Deacon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/compat.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux/compat.h') diff --git a/include/linux/compat.h b/include/linux/compat.h index 9f68e90a14ec..f2b8fe20cc8e 100644 --- a/include/linux/compat.h +++ b/include/linux/compat.h @@ -266,9 +266,9 @@ long compat_sys_shmat(int first, int second, compat_uptr_t third, int version, #else long compat_sys_semctl(int semid, int semnum, int cmd, int arg); long compat_sys_msgsnd(int msqid, struct compat_msgbuf __user *msgp, - size_t msgsz, int msgflg); + compat_ssize_t msgsz, int msgflg); long compat_sys_msgrcv(int msqid, struct compat_msgbuf __user *msgp, - size_t msgsz, long msgtyp, int msgflg); + compat_ssize_t msgsz, long msgtyp, int msgflg); long compat_sys_shmat(int shmid, compat_uptr_t shmaddr, int shmflg); #endif long compat_sys_msgctl(int first, int second, void __user *uptr); -- cgit v1.2.3 From c1d7e01d7877a397655277a920aeaa3830ed9461 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Mon, 30 Jul 2012 14:42:46 -0700 Subject: ipc: use Kconfig options for __ARCH_WANT_[COMPAT_]IPC_PARSE_VERSION Rather than #define the options manually in the architecture code, add Kconfig options for them and select them there instead. This also allows us to select the compat IPC version parsing automatically for platforms using the old compat IPC interface. Reported-by: Andrew Morton Signed-off-by: Will Deacon Cc: Arnd Bergmann Cc: Chris Metcalf Cc: Catalin Marinas Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/compat.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/linux/compat.h') diff --git a/include/linux/compat.h b/include/linux/compat.h index f2b8fe20cc8e..09b28b7369d7 100644 --- a/include/linux/compat.h +++ b/include/linux/compat.h @@ -256,7 +256,6 @@ compat_sys_get_robust_list(int pid, compat_uptr_t __user *head_ptr, compat_size_t __user *len_ptr); #ifdef CONFIG_ARCH_WANT_OLD_COMPAT_IPC -#define __ARCH_WANT_COMPAT_IPC_PARSE_VERSION long compat_sys_semctl(int first, int second, int third, void __user *uptr); long compat_sys_msgsnd(int first, int second, int third, void __user *uptr); long compat_sys_msgrcv(int first, int second, int msgtyp, int third, -- cgit v1.2.3