mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-25 13:43:55 +08:00
6934da9238
There is a use-after-free possibility in __ext4_journal_stop() in the case that we free the handle in the first jbd2_journal_stop() because we're referencing handle->h_err afterwards. This was introduced in9705acd63b
and it is wrong. Fix it by storing the handle->h_err value beforehand and avoid referencing potentially freed handle. Fixes:9705acd63b
Signed-off-by: Lukas Czerner <lczerner@redhat.com> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Cc: stable@vger.kernel.org
328 lines
7.9 KiB
C
328 lines
7.9 KiB
C
/*
|
|
* Interface between ext4 and JBD
|
|
*/
|
|
|
|
#include "ext4_jbd2.h"
|
|
|
|
#include <trace/events/ext4.h>
|
|
|
|
/* Just increment the non-pointer handle value */
|
|
static handle_t *ext4_get_nojournal(void)
|
|
{
|
|
handle_t *handle = current->journal_info;
|
|
unsigned long ref_cnt = (unsigned long)handle;
|
|
|
|
BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT);
|
|
|
|
ref_cnt++;
|
|
handle = (handle_t *)ref_cnt;
|
|
|
|
current->journal_info = handle;
|
|
return handle;
|
|
}
|
|
|
|
|
|
/* Decrement the non-pointer handle value */
|
|
static void ext4_put_nojournal(handle_t *handle)
|
|
{
|
|
unsigned long ref_cnt = (unsigned long)handle;
|
|
|
|
BUG_ON(ref_cnt == 0);
|
|
|
|
ref_cnt--;
|
|
handle = (handle_t *)ref_cnt;
|
|
|
|
current->journal_info = handle;
|
|
}
|
|
|
|
/*
|
|
* Wrappers for jbd2_journal_start/end.
|
|
*/
|
|
static int ext4_journal_check_start(struct super_block *sb)
|
|
{
|
|
journal_t *journal;
|
|
|
|
might_sleep();
|
|
if (sb->s_flags & MS_RDONLY)
|
|
return -EROFS;
|
|
WARN_ON(sb->s_writers.frozen == SB_FREEZE_COMPLETE);
|
|
journal = EXT4_SB(sb)->s_journal;
|
|
/*
|
|
* Special case here: if the journal has aborted behind our
|
|
* backs (eg. EIO in the commit thread), then we still need to
|
|
* take the FS itself readonly cleanly.
|
|
*/
|
|
if (journal && is_journal_aborted(journal)) {
|
|
ext4_abort(sb, "Detected aborted journal");
|
|
return -EROFS;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
handle_t *__ext4_journal_start_sb(struct super_block *sb, unsigned int line,
|
|
int type, int blocks, int rsv_blocks)
|
|
{
|
|
journal_t *journal;
|
|
int err;
|
|
|
|
trace_ext4_journal_start(sb, blocks, rsv_blocks, _RET_IP_);
|
|
err = ext4_journal_check_start(sb);
|
|
if (err < 0)
|
|
return ERR_PTR(err);
|
|
|
|
journal = EXT4_SB(sb)->s_journal;
|
|
if (!journal)
|
|
return ext4_get_nojournal();
|
|
return jbd2__journal_start(journal, blocks, rsv_blocks, GFP_NOFS,
|
|
type, line);
|
|
}
|
|
|
|
int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle)
|
|
{
|
|
struct super_block *sb;
|
|
int err;
|
|
int rc;
|
|
|
|
if (!ext4_handle_valid(handle)) {
|
|
ext4_put_nojournal(handle);
|
|
return 0;
|
|
}
|
|
|
|
err = handle->h_err;
|
|
if (!handle->h_transaction) {
|
|
rc = jbd2_journal_stop(handle);
|
|
return err ? err : rc;
|
|
}
|
|
|
|
sb = handle->h_transaction->t_journal->j_private;
|
|
rc = jbd2_journal_stop(handle);
|
|
|
|
if (!err)
|
|
err = rc;
|
|
if (err)
|
|
__ext4_std_error(sb, where, line, err);
|
|
return err;
|
|
}
|
|
|
|
handle_t *__ext4_journal_start_reserved(handle_t *handle, unsigned int line,
|
|
int type)
|
|
{
|
|
struct super_block *sb;
|
|
int err;
|
|
|
|
if (!ext4_handle_valid(handle))
|
|
return ext4_get_nojournal();
|
|
|
|
sb = handle->h_journal->j_private;
|
|
trace_ext4_journal_start_reserved(sb, handle->h_buffer_credits,
|
|
_RET_IP_);
|
|
err = ext4_journal_check_start(sb);
|
|
if (err < 0) {
|
|
jbd2_journal_free_reserved(handle);
|
|
return ERR_PTR(err);
|
|
}
|
|
|
|
err = jbd2_journal_start_reserved(handle, type, line);
|
|
if (err < 0)
|
|
return ERR_PTR(err);
|
|
return handle;
|
|
}
|
|
|
|
static void ext4_journal_abort_handle(const char *caller, unsigned int line,
|
|
const char *err_fn,
|
|
struct buffer_head *bh,
|
|
handle_t *handle, int err)
|
|
{
|
|
char nbuf[16];
|
|
const char *errstr = ext4_decode_error(NULL, err, nbuf);
|
|
|
|
BUG_ON(!ext4_handle_valid(handle));
|
|
|
|
if (bh)
|
|
BUFFER_TRACE(bh, "abort");
|
|
|
|
if (!handle->h_err)
|
|
handle->h_err = err;
|
|
|
|
if (is_handle_aborted(handle))
|
|
return;
|
|
|
|
printk(KERN_ERR "EXT4-fs: %s:%d: aborting transaction: %s in %s\n",
|
|
caller, line, errstr, err_fn);
|
|
|
|
jbd2_journal_abort_handle(handle);
|
|
}
|
|
|
|
int __ext4_journal_get_write_access(const char *where, unsigned int line,
|
|
handle_t *handle, struct buffer_head *bh)
|
|
{
|
|
int err = 0;
|
|
|
|
might_sleep();
|
|
|
|
if (ext4_handle_valid(handle)) {
|
|
err = jbd2_journal_get_write_access(handle, bh);
|
|
if (err)
|
|
ext4_journal_abort_handle(where, line, __func__, bh,
|
|
handle, err);
|
|
}
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* The ext4 forget function must perform a revoke if we are freeing data
|
|
* which has been journaled. Metadata (eg. indirect blocks) must be
|
|
* revoked in all cases.
|
|
*
|
|
* "bh" may be NULL: a metadata block may have been freed from memory
|
|
* but there may still be a record of it in the journal, and that record
|
|
* still needs to be revoked.
|
|
*
|
|
* If the handle isn't valid we're not journaling, but we still need to
|
|
* call into ext4_journal_revoke() to put the buffer head.
|
|
*/
|
|
int __ext4_forget(const char *where, unsigned int line, handle_t *handle,
|
|
int is_metadata, struct inode *inode,
|
|
struct buffer_head *bh, ext4_fsblk_t blocknr)
|
|
{
|
|
int err;
|
|
|
|
might_sleep();
|
|
|
|
trace_ext4_forget(inode, is_metadata, blocknr);
|
|
BUFFER_TRACE(bh, "enter");
|
|
|
|
jbd_debug(4, "forgetting bh %p: is_metadata = %d, mode %o, "
|
|
"data mode %x\n",
|
|
bh, is_metadata, inode->i_mode,
|
|
test_opt(inode->i_sb, DATA_FLAGS));
|
|
|
|
/* In the no journal case, we can just do a bforget and return */
|
|
if (!ext4_handle_valid(handle)) {
|
|
bforget(bh);
|
|
return 0;
|
|
}
|
|
|
|
/* Never use the revoke function if we are doing full data
|
|
* journaling: there is no need to, and a V1 superblock won't
|
|
* support it. Otherwise, only skip the revoke on un-journaled
|
|
* data blocks. */
|
|
|
|
if (test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA ||
|
|
(!is_metadata && !ext4_should_journal_data(inode))) {
|
|
if (bh) {
|
|
BUFFER_TRACE(bh, "call jbd2_journal_forget");
|
|
err = jbd2_journal_forget(handle, bh);
|
|
if (err)
|
|
ext4_journal_abort_handle(where, line, __func__,
|
|
bh, handle, err);
|
|
return err;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* data!=journal && (is_metadata || should_journal_data(inode))
|
|
*/
|
|
BUFFER_TRACE(bh, "call jbd2_journal_revoke");
|
|
err = jbd2_journal_revoke(handle, blocknr, bh);
|
|
if (err) {
|
|
ext4_journal_abort_handle(where, line, __func__,
|
|
bh, handle, err);
|
|
__ext4_abort(inode->i_sb, where, line,
|
|
"error %d when attempting revoke", err);
|
|
}
|
|
BUFFER_TRACE(bh, "exit");
|
|
return err;
|
|
}
|
|
|
|
int __ext4_journal_get_create_access(const char *where, unsigned int line,
|
|
handle_t *handle, struct buffer_head *bh)
|
|
{
|
|
int err = 0;
|
|
|
|
if (ext4_handle_valid(handle)) {
|
|
err = jbd2_journal_get_create_access(handle, bh);
|
|
if (err)
|
|
ext4_journal_abort_handle(where, line, __func__,
|
|
bh, handle, err);
|
|
}
|
|
return err;
|
|
}
|
|
|
|
int __ext4_handle_dirty_metadata(const char *where, unsigned int line,
|
|
handle_t *handle, struct inode *inode,
|
|
struct buffer_head *bh)
|
|
{
|
|
int err = 0;
|
|
|
|
might_sleep();
|
|
|
|
set_buffer_meta(bh);
|
|
set_buffer_prio(bh);
|
|
if (ext4_handle_valid(handle)) {
|
|
err = jbd2_journal_dirty_metadata(handle, bh);
|
|
/* Errors can only happen due to aborted journal or a nasty bug */
|
|
if (!is_handle_aborted(handle) && WARN_ON_ONCE(err)) {
|
|
ext4_journal_abort_handle(where, line, __func__, bh,
|
|
handle, err);
|
|
if (inode == NULL) {
|
|
pr_err("EXT4: jbd2_journal_dirty_metadata "
|
|
"failed: handle type %u started at "
|
|
"line %u, credits %u/%u, errcode %d",
|
|
handle->h_type,
|
|
handle->h_line_no,
|
|
handle->h_requested_credits,
|
|
handle->h_buffer_credits, err);
|
|
return err;
|
|
}
|
|
ext4_error_inode(inode, where, line,
|
|
bh->b_blocknr,
|
|
"journal_dirty_metadata failed: "
|
|
"handle type %u started at line %u, "
|
|
"credits %u/%u, errcode %d",
|
|
handle->h_type,
|
|
handle->h_line_no,
|
|
handle->h_requested_credits,
|
|
handle->h_buffer_credits, err);
|
|
}
|
|
} else {
|
|
if (inode)
|
|
mark_buffer_dirty_inode(bh, inode);
|
|
else
|
|
mark_buffer_dirty(bh);
|
|
if (inode && inode_needs_sync(inode)) {
|
|
sync_dirty_buffer(bh);
|
|
if (buffer_req(bh) && !buffer_uptodate(bh)) {
|
|
struct ext4_super_block *es;
|
|
|
|
es = EXT4_SB(inode->i_sb)->s_es;
|
|
es->s_last_error_block =
|
|
cpu_to_le64(bh->b_blocknr);
|
|
ext4_error_inode(inode, where, line,
|
|
bh->b_blocknr,
|
|
"IO error syncing itable block");
|
|
err = -EIO;
|
|
}
|
|
}
|
|
}
|
|
return err;
|
|
}
|
|
|
|
int __ext4_handle_dirty_super(const char *where, unsigned int line,
|
|
handle_t *handle, struct super_block *sb)
|
|
{
|
|
struct buffer_head *bh = EXT4_SB(sb)->s_sbh;
|
|
int err = 0;
|
|
|
|
ext4_superblock_csum_set(sb);
|
|
if (ext4_handle_valid(handle)) {
|
|
err = jbd2_journal_dirty_metadata(handle, bh);
|
|
if (err)
|
|
ext4_journal_abort_handle(where, line, __func__,
|
|
bh, handle, err);
|
|
} else
|
|
mark_buffer_dirty(bh);
|
|
return err;
|
|
}
|