fs: split off do_getxattr from getxattr

This splits off do_getxattr function from the getxattr function. This will
allow io_uring to call it from its io worker.

Signed-off-by: Stefan Roesch <shr@fb.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/20220323154420.3301504-3-shr@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Stefan Roesch 2022-04-24 18:13:50 -06:00 committed by Jens Axboe
parent 1a91794ce8
commit c975cad931
2 changed files with 43 additions and 21 deletions

View File

@ -212,6 +212,11 @@ struct xattr_ctx {
unsigned int flags;
};
ssize_t do_getxattr(struct user_namespace *mnt_userns,
struct dentry *d,
struct xattr_ctx *ctx);
int setxattr_copy(const char __user *name, struct xattr_ctx *ctx);
int do_setxattr(struct user_namespace *mnt_userns, struct dentry *dentry,
struct xattr_ctx *ctx);

View File

@ -676,44 +676,61 @@ SYSCALL_DEFINE5(fsetxattr, int, fd, const char __user *, name,
/*
* Extended attribute GET operations
*/
static ssize_t
getxattr(struct user_namespace *mnt_userns, struct dentry *d,
const char __user *name, void __user *value, size_t size)
ssize_t
do_getxattr(struct user_namespace *mnt_userns, struct dentry *d,
struct xattr_ctx *ctx)
{
ssize_t error;
void *kvalue = NULL;
char kname[XATTR_NAME_MAX + 1];
char *kname = ctx->kname->name;
error = strncpy_from_user(kname, name, sizeof(kname));
if (error == 0 || error == sizeof(kname))
error = -ERANGE;
if (error < 0)
return error;
if (size) {
if (size > XATTR_SIZE_MAX)
size = XATTR_SIZE_MAX;
kvalue = kvzalloc(size, GFP_KERNEL);
if (!kvalue)
if (ctx->size) {
if (ctx->size > XATTR_SIZE_MAX)
ctx->size = XATTR_SIZE_MAX;
ctx->kvalue = kvzalloc(ctx->size, GFP_KERNEL);
if (!ctx->kvalue)
return -ENOMEM;
}
error = vfs_getxattr(mnt_userns, d, kname, kvalue, size);
error = vfs_getxattr(mnt_userns, d, kname, ctx->kvalue, ctx->size);
if (error > 0) {
if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) ||
(strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0))
posix_acl_fix_xattr_to_user(mnt_userns, d_inode(d),
kvalue, error);
if (size && copy_to_user(value, kvalue, error))
ctx->kvalue, error);
if (ctx->size && copy_to_user(ctx->value, ctx->kvalue, error))
error = -EFAULT;
} else if (error == -ERANGE && size >= XATTR_SIZE_MAX) {
} else if (error == -ERANGE && ctx->size >= XATTR_SIZE_MAX) {
/* The file system tried to returned a value bigger
than XATTR_SIZE_MAX bytes. Not possible. */
error = -E2BIG;
}
kvfree(kvalue);
return error;
}
static ssize_t
getxattr(struct user_namespace *mnt_userns, struct dentry *d,
const char __user *name, void __user *value, size_t size)
{
ssize_t error;
struct xattr_name kname;
struct xattr_ctx ctx = {
.value = value,
.kvalue = NULL,
.size = size,
.kname = &kname,
.flags = 0,
};
error = strncpy_from_user(kname.name, name, sizeof(kname.name));
if (error == 0 || error == sizeof(kname.name))
error = -ERANGE;
if (error < 0)
return error;
error = do_getxattr(mnt_userns, d, &ctx);
kvfree(ctx.kvalue);
return error;
}