| Message ID | 20200114081051.297488-5-hch@lst.de (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [01/29] xfs: remove the ATTR_INCOMPLETE flag | expand |
On Tue, Jan 14, 2020 at 09:10:26AM +0100, Christoph Hellwig wrote: > Simplify the user copy code by using strndup_user. This means that we > now do one memory allocation per operation instead of one per ioctl, > but memory allocations are cheap compared to the actual file system > operations. > > Signed-off-by: Christoph Hellwig <hch@lst.de> Looks ok, Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> --D > --- > fs/xfs/xfs_ioctl.c | 17 +++++------------ > fs/xfs/xfs_ioctl32.c | 17 +++++------------ > 2 files changed, 10 insertions(+), 24 deletions(-) > > diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c > index 6bd0684a3528..f4d5c865e29e 100644 > --- a/fs/xfs/xfs_ioctl.c > +++ b/fs/xfs/xfs_ioctl.c > @@ -446,11 +446,6 @@ xfs_attrmulti_by_handle( > goto out_dput; > } > > - error = -ENOMEM; > - attr_name = kmalloc(MAXNAMELEN, GFP_KERNEL); > - if (!attr_name) > - goto out_kfree_ops; > - > error = 0; > for (i = 0; i < am_hreq.opcount; i++) { > if ((ops[i].am_flags & ATTR_ROOT) && > @@ -460,12 +455,11 @@ xfs_attrmulti_by_handle( > } > ops[i].am_flags &= ~ATTR_KERNEL_FLAGS; > > - ops[i].am_error = strncpy_from_user((char *)attr_name, > - ops[i].am_attrname, MAXNAMELEN); > - if (ops[i].am_error == 0 || ops[i].am_error == MAXNAMELEN) > - error = -ERANGE; > - if (ops[i].am_error < 0) > + attr_name = strndup_user(ops[i].am_attrname, MAXNAMELEN); > + if (IS_ERR(attr_name)) { > + ops[i].am_error = PTR_ERR(attr_name); > break; > + } > > switch (ops[i].am_opcode) { > case ATTR_OP_GET: > @@ -496,13 +490,12 @@ xfs_attrmulti_by_handle( > default: > ops[i].am_error = -EINVAL; > } > + kfree(attr_name); > } > > if (copy_to_user(am_hreq.ops, ops, size)) > error = -EFAULT; > > - kfree(attr_name); > - out_kfree_ops: > kfree(ops); > out_dput: > dput(dentry); > diff --git a/fs/xfs/xfs_ioctl32.c b/fs/xfs/xfs_ioctl32.c > index 1092c66e48d6..e6a7f619a54c 100644 > --- a/fs/xfs/xfs_ioctl32.c > +++ b/fs/xfs/xfs_ioctl32.c > @@ -443,11 +443,6 @@ xfs_compat_attrmulti_by_handle( > goto out_dput; > } > > - error = -ENOMEM; > - attr_name = kmalloc(MAXNAMELEN, GFP_KERNEL); > - if (!attr_name) > - goto out_kfree_ops; > - > error = 0; > for (i = 0; i < am_hreq.opcount; i++) { > if ((ops[i].am_flags & ATTR_ROOT) && > @@ -457,13 +452,12 @@ xfs_compat_attrmulti_by_handle( > } > ops[i].am_flags &= ~ATTR_KERNEL_FLAGS; > > - ops[i].am_error = strncpy_from_user((char *)attr_name, > - compat_ptr(ops[i].am_attrname), > + attr_name = strndup_user(compat_ptr(ops[i].am_attrname), > MAXNAMELEN); > - if (ops[i].am_error == 0 || ops[i].am_error == MAXNAMELEN) > - error = -ERANGE; > - if (ops[i].am_error < 0) > + if (IS_ERR(attr_name)) { > + ops[i].am_error = PTR_ERR(attr_name); > break; > + } > > switch (ops[i].am_opcode) { > case ATTR_OP_GET: > @@ -494,13 +488,12 @@ xfs_compat_attrmulti_by_handle( > default: > ops[i].am_error = -EINVAL; > } > + kfree(attr_name); > } > > if (copy_to_user(compat_ptr(am_hreq.ops), ops, size)) > error = -EFAULT; > > - kfree(attr_name); > - out_kfree_ops: > kfree(ops); > out_dput: > dput(dentry); > -- > 2.24.1 >
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c index 6bd0684a3528..f4d5c865e29e 100644 --- a/fs/xfs/xfs_ioctl.c +++ b/fs/xfs/xfs_ioctl.c @@ -446,11 +446,6 @@ xfs_attrmulti_by_handle( goto out_dput; } - error = -ENOMEM; - attr_name = kmalloc(MAXNAMELEN, GFP_KERNEL); - if (!attr_name) - goto out_kfree_ops; - error = 0; for (i = 0; i < am_hreq.opcount; i++) { if ((ops[i].am_flags & ATTR_ROOT) && @@ -460,12 +455,11 @@ xfs_attrmulti_by_handle( } ops[i].am_flags &= ~ATTR_KERNEL_FLAGS; - ops[i].am_error = strncpy_from_user((char *)attr_name, - ops[i].am_attrname, MAXNAMELEN); - if (ops[i].am_error == 0 || ops[i].am_error == MAXNAMELEN) - error = -ERANGE; - if (ops[i].am_error < 0) + attr_name = strndup_user(ops[i].am_attrname, MAXNAMELEN); + if (IS_ERR(attr_name)) { + ops[i].am_error = PTR_ERR(attr_name); break; + } switch (ops[i].am_opcode) { case ATTR_OP_GET: @@ -496,13 +490,12 @@ xfs_attrmulti_by_handle( default: ops[i].am_error = -EINVAL; } + kfree(attr_name); } if (copy_to_user(am_hreq.ops, ops, size)) error = -EFAULT; - kfree(attr_name); - out_kfree_ops: kfree(ops); out_dput: dput(dentry); diff --git a/fs/xfs/xfs_ioctl32.c b/fs/xfs/xfs_ioctl32.c index 1092c66e48d6..e6a7f619a54c 100644 --- a/fs/xfs/xfs_ioctl32.c +++ b/fs/xfs/xfs_ioctl32.c @@ -443,11 +443,6 @@ xfs_compat_attrmulti_by_handle( goto out_dput; } - error = -ENOMEM; - attr_name = kmalloc(MAXNAMELEN, GFP_KERNEL); - if (!attr_name) - goto out_kfree_ops; - error = 0; for (i = 0; i < am_hreq.opcount; i++) { if ((ops[i].am_flags & ATTR_ROOT) && @@ -457,13 +452,12 @@ xfs_compat_attrmulti_by_handle( } ops[i].am_flags &= ~ATTR_KERNEL_FLAGS; - ops[i].am_error = strncpy_from_user((char *)attr_name, - compat_ptr(ops[i].am_attrname), + attr_name = strndup_user(compat_ptr(ops[i].am_attrname), MAXNAMELEN); - if (ops[i].am_error == 0 || ops[i].am_error == MAXNAMELEN) - error = -ERANGE; - if (ops[i].am_error < 0) + if (IS_ERR(attr_name)) { + ops[i].am_error = PTR_ERR(attr_name); break; + } switch (ops[i].am_opcode) { case ATTR_OP_GET: @@ -494,13 +488,12 @@ xfs_compat_attrmulti_by_handle( default: ops[i].am_error = -EINVAL; } + kfree(attr_name); } if (copy_to_user(compat_ptr(am_hreq.ops), ops, size)) error = -EFAULT; - kfree(attr_name); - out_kfree_ops: kfree(ops); out_dput: dput(dentry);
Simplify the user copy code by using strndup_user. This means that we now do one memory allocation per operation instead of one per ioctl, but memory allocations are cheap compared to the actual file system operations. Signed-off-by: Christoph Hellwig <hch@lst.de> --- fs/xfs/xfs_ioctl.c | 17 +++++------------ fs/xfs/xfs_ioctl32.c | 17 +++++------------ 2 files changed, 10 insertions(+), 24 deletions(-)