diff options
author | Jens Axboe <jaxboe@fusionio.com> | 2010-06-01 12:42:12 +0200 |
---|---|---|
committer | Jens Axboe <jaxboe@fusionio.com> | 2010-06-01 12:42:12 +0200 |
commit | b4ca761577535b2b4d153689ee97342797dfff05 (patch) | |
tree | 29054d55508f1faa22ec32acf7c245751af03348 /fs/compat.c | |
parent | 28f4197e5d4707311febeec8a0eb97cb5fd93c97 (diff) | |
parent | 67a3e12b05e055c0415c556a315a3d3eb637e29e (diff) |
Merge branch 'master' into for-linus
Conflicts:
fs/pipe.c
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Diffstat (limited to 'fs/compat.c')
-rw-r--r-- | fs/compat.c | 132 |
1 files changed, 78 insertions, 54 deletions
diff --git a/fs/compat.c b/fs/compat.c index 05448730f840..f0b391c50552 100644 --- a/fs/compat.c +++ b/fs/compat.c @@ -568,6 +568,79 @@ out: return ret; } +/* A write operation does a read from user space and vice versa */ +#define vrfy_dir(type) ((type) == READ ? VERIFY_WRITE : VERIFY_READ) + +ssize_t compat_rw_copy_check_uvector(int type, + const struct compat_iovec __user *uvector, unsigned long nr_segs, + unsigned long fast_segs, struct iovec *fast_pointer, + struct iovec **ret_pointer) +{ + compat_ssize_t tot_len; + struct iovec *iov = *ret_pointer = fast_pointer; + ssize_t ret = 0; + int seg; + + /* + * SuS says "The readv() function *may* fail if the iovcnt argument + * was less than or equal to 0, or greater than {IOV_MAX}. Linux has + * traditionally returned zero for zero segments, so... + */ + if (nr_segs == 0) + goto out; + + ret = -EINVAL; + if (nr_segs > UIO_MAXIOV || nr_segs < 0) + goto out; + if (nr_segs > fast_segs) { + ret = -ENOMEM; + iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL); + if (iov == NULL) { + *ret_pointer = fast_pointer; + goto out; + } + } + *ret_pointer = iov; + + /* + * Single unix specification: + * We should -EINVAL if an element length is not >= 0 and fitting an + * ssize_t. The total length is fitting an ssize_t + * + * Be careful here because iov_len is a size_t not an ssize_t + */ + tot_len = 0; + ret = -EINVAL; + for (seg = 0; seg < nr_segs; seg++) { + compat_ssize_t tmp = tot_len; + compat_uptr_t buf; + compat_ssize_t len; + + if (__get_user(len, &uvector->iov_len) || + __get_user(buf, &uvector->iov_base)) { + ret = -EFAULT; + goto out; + } + if (len < 0) /* size_t not fitting in compat_ssize_t .. */ + goto out; + tot_len += len; + if (tot_len < tmp) /* maths overflow on the compat_ssize_t */ + goto out; + if (!access_ok(vrfy_dir(type), buf, len)) { + ret = -EFAULT; + goto out; + } + iov->iov_base = compat_ptr(buf); + iov->iov_len = (compat_size_t) len; + uvector++; + iov++; + } + ret = tot_len; + +out: + return ret; +} + static inline long copy_iocb(long nr, u32 __user *ptr32, struct iocb __user * __user *ptr64) { @@ -600,7 +673,7 @@ compat_sys_io_submit(aio_context_t ctx_id, int nr, u32 __user *iocb) iocb64 = compat_alloc_user_space(nr * sizeof(*iocb64)); ret = copy_iocb(nr, iocb, iocb64); if (!ret) - ret = sys_io_submit(ctx_id, nr, iocb64); + ret = do_io_submit(ctx_id, nr, iocb64, 1); return ret; } @@ -1077,70 +1150,21 @@ static ssize_t compat_do_readv_writev(int type, struct file *file, { compat_ssize_t tot_len; struct iovec iovstack[UIO_FASTIOV]; - struct iovec *iov=iovstack, *vector; + struct iovec *iov; ssize_t ret; - int seg; io_fn_t fn; iov_fn_t fnv; - /* - * SuS says "The readv() function *may* fail if the iovcnt argument - * was less than or equal to 0, or greater than {IOV_MAX}. Linux has - * traditionally returned zero for zero segments, so... - */ - ret = 0; - if (nr_segs == 0) - goto out; - - /* - * First get the "struct iovec" from user memory and - * verify all the pointers - */ ret = -EINVAL; - if ((nr_segs > UIO_MAXIOV) || (nr_segs <= 0)) - goto out; if (!file->f_op) goto out; - if (nr_segs > UIO_FASTIOV) { - ret = -ENOMEM; - iov = kmalloc(nr_segs*sizeof(struct iovec), GFP_KERNEL); - if (!iov) - goto out; - } + ret = -EFAULT; if (!access_ok(VERIFY_READ, uvector, nr_segs*sizeof(*uvector))) goto out; - /* - * Single unix specification: - * We should -EINVAL if an element length is not >= 0 and fitting an - * ssize_t. The total length is fitting an ssize_t - * - * Be careful here because iov_len is a size_t not an ssize_t - */ - tot_len = 0; - vector = iov; - ret = -EINVAL; - for (seg = 0 ; seg < nr_segs; seg++) { - compat_ssize_t tmp = tot_len; - compat_ssize_t len; - compat_uptr_t buf; - - if (__get_user(len, &uvector->iov_len) || - __get_user(buf, &uvector->iov_base)) { - ret = -EFAULT; - goto out; - } - if (len < 0) /* size_t not fitting an compat_ssize_t .. */ - goto out; - tot_len += len; - if (tot_len < tmp) /* maths overflow on the compat_ssize_t */ - goto out; - vector->iov_base = compat_ptr(buf); - vector->iov_len = (compat_size_t) len; - uvector++; - vector++; - } + tot_len = compat_rw_copy_check_uvector(type, uvector, nr_segs, + UIO_FASTIOV, iovstack, &iov); if (tot_len == 0) { ret = 0; goto out; |