orangefs: get rid of readdir_handle_s

no point, really - we couldn't keep those across the calls of
getdents(); it would be too easy to DoS, having all slots exhausted.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
This commit is contained in:
Al Viro 2016-02-16 19:54:13 -05:00 committed by Mike Marshall
parent fecd86aac5
commit 9f5e2f7f1b

View File

@ -8,11 +8,6 @@
#include "orangefs-kernel.h"
#include "orangefs-bufmap.h"
struct readdir_handle_s {
struct orangefs_readdir_response_s readdir_response;
void *dents_buf;
};
/*
* decode routine used by kmod to deal with the blob sent from
* userspace for readdirs. The blob contains zero or more of these
@ -141,44 +136,6 @@ out:
return ret;
}
static long readdir_handle_ctor(struct readdir_handle_s *rhandle, void *buf,
size_t size)
{
long ret;
if (buf == NULL) {
gossip_err
("Invalid NULL buffer specified in readdir_handle_ctor\n");
return -ENOMEM;
}
rhandle->dents_buf = buf;
ret = decode_dirents(buf, size, &rhandle->readdir_response);
if (ret < 0) {
gossip_err("Could not decode readdir from buffer %ld\n", ret);
gossip_debug(GOSSIP_DIR_DEBUG, "vfree %p\n", buf);
vfree(buf);
rhandle->dents_buf = NULL;
}
return ret;
}
static void readdir_handle_dtor(struct readdir_handle_s *rhandle)
{
if (rhandle == NULL)
return;
/* kfree(NULL) is safe */
kfree(rhandle->readdir_response.dirent_array);
rhandle->readdir_response.dirent_array = NULL;
if (rhandle->dents_buf) {
gossip_debug(GOSSIP_DIR_DEBUG, "vfree %p\n",
rhandle->dents_buf);
vfree(rhandle->dents_buf);
rhandle->dents_buf = NULL;
}
}
/*
* Read directory entries from an instance of an open directory.
*/
@ -198,7 +155,8 @@ static int orangefs_readdir(struct file *file, struct dir_context *ctx)
struct orangefs_kernel_op_s *new_op = NULL;
struct orangefs_inode_s *orangefs_inode = ORANGEFS_I(dentry->d_inode);
int buffer_full = 0;
struct readdir_handle_s rhandle;
struct orangefs_readdir_response_s readdir_response;
void *dents_buf;
int i = 0;
int len = 0;
ino_t current_ino = 0;
@ -224,8 +182,7 @@ static int orangefs_readdir(struct file *file, struct dir_context *ctx)
"orangefs_readdir called on %s (pos=%llu)\n",
dentry->d_name.name, llu(pos));
rhandle.dents_buf = NULL;
memset(&rhandle.readdir_response, 0, sizeof(rhandle.readdir_response));
memset(&readdir_response, 0, sizeof(readdir_response));
new_op = op_alloc(ORANGEFS_VFS_OP_READDIR);
if (!new_op)
@ -278,7 +235,7 @@ get_new_buffer_index:
if (ret == -EIO && op_state_purged(new_op)) {
gossip_err("%s: Client is down. Aborting readdir call.\n",
__func__);
goto out_free_op;
goto out_slot;
}
if (ret < 0 || new_op->downcall.status != 0) {
@ -287,18 +244,22 @@ get_new_buffer_index:
new_op->downcall.status);
if (ret >= 0)
ret = new_op->downcall.status;
goto out_free_op;
goto out_slot;
}
bytes_decoded =
readdir_handle_ctor(&rhandle,
new_op->downcall.trailer_buf,
new_op->downcall.trailer_size);
dents_buf = new_op->downcall.trailer_buf;
if (dents_buf == NULL) {
gossip_err("Invalid NULL buffer in readdir response\n");
ret = -ENOMEM;
goto out_slot;
}
bytes_decoded = decode_dirents(dents_buf, new_op->downcall.trailer_size,
&readdir_response);
if (bytes_decoded < 0) {
gossip_err("orangefs_readdir: Could not decode trailer buffer into a readdir response %d\n",
ret);
ret = bytes_decoded;
goto out_free_op;
gossip_err("Could not decode readdir from buffer %d\n", ret);
goto out_vfree;
}
if (bytes_decoded != new_op->downcall.trailer_size) {
@ -345,14 +306,14 @@ get_new_buffer_index:
gossip_debug(GOSSIP_DIR_DEBUG,
"%s: dirent_outcount:%d:\n",
__func__,
rhandle.readdir_response.orangefs_dirent_outcount);
readdir_response.orangefs_dirent_outcount);
for (i = ctx->pos;
i < rhandle.readdir_response.orangefs_dirent_outcount;
i < readdir_response.orangefs_dirent_outcount;
i++) {
len = rhandle.readdir_response.dirent_array[i].d_length;
current_entry = rhandle.readdir_response.dirent_array[i].d_name;
len = readdir_response.dirent_array[i].d_length;
current_entry = readdir_response.dirent_array[i].d_name;
current_ino = orangefs_khandle_to_ino(
&(rhandle.readdir_response.dirent_array[i].khandle));
&readdir_response.dirent_array[i].khandle);
gossip_debug(GOSSIP_DIR_DEBUG,
"calling dir_emit for %s with len %d"
@ -382,14 +343,14 @@ get_new_buffer_index:
* getting another batch...
*/
if (ret) {
*ptoken = rhandle.readdir_response.token;
*ptoken = readdir_response.token;
ctx->pos = ORANGEFS_ITERATE_NEXT;
}
/*
* Did we hit the end of the directory?
*/
if (rhandle.readdir_response.token == ORANGEFS_READDIR_END &&
if (readdir_response.token == ORANGEFS_READDIR_END &&
!buffer_full) {
gossip_debug(GOSSIP_DIR_DEBUG,
"End of dir detected; setting ctx->pos to ORANGEFS_READDIR_END.\n");
@ -397,7 +358,13 @@ get_new_buffer_index:
}
out_destroy_handle:
readdir_handle_dtor(&rhandle);
/* kfree(NULL) is safe */
kfree(readdir_response.dirent_array);
out_vfree:
gossip_debug(GOSSIP_DIR_DEBUG, "vfree %p\n", dents_buf);
vfree(dents_buf);
out_slot:
orangefs_readdir_index_put(buffer_index);
out_free_op:
op_release(new_op);
gossip_debug(GOSSIP_DIR_DEBUG, "orangefs_readdir returning %d\n", ret);