The patch titled Subject: ipc: compat: use signed size_t types for msgsnd and msgrcv has been added to the -mm tree. Its filename is ipc-compat-use-signed-size_t-types-for-msgsnd-and-msgrcv.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Will Deacon <will.deacon@xxxxxxx> 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 <arnd@xxxxxxxx> Acked-by: Chris Metcalf <cmetcalf@xxxxxxxxxx> Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx> Signed-off-by: Will Deacon <will.deacon@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/compat.h | 4 ++-- ipc/compat.c | 8 ++++---- 2 files changed, 6 insertions(+), 6 deletions(-) diff -puN include/linux/compat.h~ipc-compat-use-signed-size_t-types-for-msgsnd-and-msgrcv include/linux/compat.h --- a/include/linux/compat.h~ipc-compat-use-signed-size_t-types-for-msgsnd-and-msgrcv +++ a/include/linux/compat.h @@ -266,9 +266,9 @@ long compat_sys_shmat(int first, int sec #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); diff -puN ipc/compat.c~ipc-compat-use-signed-size_t-types-for-msgsnd-and-msgrcv ipc/compat.c --- a/ipc/compat.c~ipc-compat-use-signed-size_t-types-for-msgsnd-and-msgrcv +++ a/ipc/compat.c @@ -373,21 +373,21 @@ long compat_sys_semctl(int semid, int se } long compat_sys_msgsnd(int msqid, struct compat_msgbuf __user *msgp, - size_t msgsz, int msgflg) + compat_ssize_t msgsz, int msgflg) { compat_long_t mtype; if (get_user(mtype, &msgp->mtype)) return -EFAULT; - return do_msgsnd(msqid, mtype, msgp->mtext, msgsz, msgflg); + return do_msgsnd(msqid, mtype, msgp->mtext, (ssize_t)msgsz, 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 err, mtype; - err = do_msgrcv(msqid, &mtype, msgp->mtext, msgsz, msgtyp, msgflg); + err = do_msgrcv(msqid, &mtype, msgp->mtext, (ssize_t)msgsz, msgtyp, msgflg); if (err < 0) goto out; _ Subject: Subject: ipc: compat: use signed size_t types for msgsnd and msgrcv Patches currently in -mm which might be from will.deacon@xxxxxxx are linux-next.patch ipc-add-compat_shmlba-support.patch ipc-allow-compat-ipc-version-field-parsing-if-arch_want_old_compat_ipc.patch ipc-compat-use-signed-size_t-types-for-msgsnd-and-msgrcv.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html