ipc/shm: some shmat cleanups

Clean up early flag and address some minutia.

Link: http://lkml.kernel.org/r/1486673582-6979-3-git-send-email-dave@stgolabs.net
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Davidlohr Bueso 2017-05-08 15:57:03 -07:00 committed by Linus Torvalds
parent 046aa1265f
commit f0cb88026f

View File

@ -1095,11 +1095,11 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg,
ulong *raddr, unsigned long shmlba)
{
struct shmid_kernel *shp;
unsigned long addr;
unsigned long addr = (unsigned long)shmaddr;
unsigned long size;
struct file *file;
int err;
unsigned long flags;
unsigned long flags = MAP_SHARED;
unsigned long prot;
int acc_mode;
struct ipc_namespace *ns;
@ -1111,7 +1111,8 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg,
err = -EINVAL;
if (shmid < 0)
goto out;
else if ((addr = (ulong)shmaddr)) {
if (addr) {
if (addr & (shmlba - 1)) {
/*
* Round down to the nearest multiple of shmlba.
@ -1126,13 +1127,10 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg,
#endif
goto out;
}
flags = MAP_SHARED | MAP_FIXED;
} else {
if ((shmflg & SHM_REMAP))
goto out;
flags = MAP_SHARED;
}
flags |= MAP_FIXED;
} else if ((shmflg & SHM_REMAP))
goto out;
if (shmflg & SHM_RDONLY) {
prot = PROT_READ;