summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorChristoph Hellwig <hch@lst.de>2020-02-26 17:30:31 -0800
committerDarrick J. Wong <darrick.wong@oracle.com>2020-03-02 20:55:52 -0800
commit2282a9e65177b425aaab4d8228f98f5c09fc778a (patch)
treeb78179d9a41eecbe80df4ad0aeff7e136da23be5
parent6cc4f4fff10d38e95994e740f1b1d260c6fe8506 (diff)
downloadlinux-2282a9e65177b425aaab4d8228f98f5c09fc778a.tar.bz2
xfs: use strndup_user in XFS_IOC_ATTRMULTI_BY_HANDLE
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. Also the error for an invalid path is now EINVAL or EFAULT instead of the previous odd and undocumented ERANGE. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
-rw-r--r--fs/xfs/xfs_ioctl.c17
-rw-r--r--fs/xfs/xfs_ioctl32.c17
2 files changed, 10 insertions, 24 deletions
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index ef0508945267..df658eacbe58 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -448,11 +448,6 @@ 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) &&
@@ -462,12 +457,11 @@ 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:
@@ -498,13 +492,12 @@ 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 e085f304e539..936c2f62fb6c 100644
--- a/fs/xfs/xfs_ioctl32.c
+++ b/fs/xfs/xfs_ioctl32.c
@@ -445,11 +445,6 @@ 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) &&
@@ -459,13 +454,12 @@ 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:
@@ -496,13 +490,12 @@ 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);