kernel/linux.git/include/target/target_core_base.h, branch v4.19.77

scsi: target/core: Make sure that target_wait_for_sess_cmds() waits long enough

2019-01-26T08:32:38+00:00

[ Upstream commit ad669505c4e9db9af9faeb5c51aa399326a80d91 ] A session must only be released after all code that accesses the session structure has finished. Make sure that this is the case by introducing a new command counter per session that is only decremented after the .release_cmd() callback has finished. This patch fixes the following crash: BUG: KASAN: use-after-free in do_raw_spin_lock+0x1c/0x130 Read of size 4 at addr ffff8801534b16e4 by task rmdir/14805 CPU: 16 PID: 14805 Comm: rmdir Not tainted 4.18.0-rc2-dbg+ #5 Call Trace: dump_stack+0xa4/0xf5 print_address_description+0x6f/0x270 kasan_report+0x241/0x360 __asan_load4+0x78/0x80 do_raw_spin_lock+0x1c/0x130 _raw_spin_lock_irqsave+0x52/0x60 srpt_set_ch_state+0x27/0x70 [ib_srpt] srpt_disconnect_ch+0x1b/0xc0 [ib_srpt] srpt_close_session+0xa8/0x260 [ib_srpt] target_shutdown_sessions+0x170/0x180 [target_core_mod] core_tpg_del_initiator_node_acl+0xf3/0x200 [target_core_mod] target_fabric_nacl_base_release+0x25/0x30 [target_core_mod] config_item_release+0x9c/0x110 [configfs] config_item_put+0x26/0x30 [configfs] configfs_rmdir+0x3b8/0x510 [configfs] vfs_rmdir+0xb3/0x1e0 do_rmdir+0x262/0x2c0 do_syscall_64+0x77/0x230 entry_SYSCALL_64_after_hwframe+0x49/0xbe Cc: Nicholas Bellinger Cc: Mike Christie Cc: Christoph Hellwig Cc: David Disseldorp Cc: Hannes Reinecke Signed-off-by: Bart Van Assche Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin

scsi: target: Remove se_dev_entry.ua_count

2018-07-02T20:44:32+00:00

se_dev_entry.ua_count is only used to check whether or not se_dev_entry.ua_list is empty. Use list_empty_careful() instead. Checking whether or not ua_list is empty without holding the lock that protects that list is fine because the code that dequeues from that list will check again whether or not that list is empty. Signed-off-by: Bart Van Assche Reviewed-by: Mike Christie Cc: Mike Christie Cc: Christoph Hellwig Cc: Hannes Reinecke Signed-off-by: Martin K. Petersen

scsi: target: Simplify the code for waiting for command completion

2018-07-02T20:44:31+00:00

Instead of embedding the completion that is used for waiting for command completion in struct se_cmd, let the context that waits for command completion allocate it. This makes it possible to have a single code path for non-aborted and aborted commands in target_release_cmd_kref() and avoids that transport_generic_free_cmd() has to call cmd->se_tfo->release_cmd() directly. This patch does not change any functionality. Note: transport_generic_free_cmd() only waits until the se_cmd reference count has reached zero after it has set both CMD_T_FABRIC_STOP and CMD_T_ABORTED. Signed-off-by: Bart Van Assche Reviewed-by: Mike Christie Cc: Hannes Reinecke Cc: Christoph Hellwig Signed-off-by: Martin K. Petersen

scsi: target: Make the session shutdown code also wait for commands that are being aborted

2018-07-02T20:44:31+00:00

Target drivers must call target_sess_cmd_list_set_waiting() and target_wait_for_sess_cmds() before freeing a session. Since freeing a session is only safe after all commands that are associated with a session have finished, make target_wait_for_sess_cmds() also wait for commands that are being aborted. Instead of setting a flag in each pending command from target_sess_cmd_list_set_waiting() and waiting in target_wait_for_sess_cmds() on a per-command completion, only set a per-session flag in the former function and wait on a per-session completion in the latter function. This change is safe because once a SCSI initiator system has submitted a command a target system is always allowed to execute it to completion. See also commit 0f4a943168f3 ("target: Fix remote-port TMR ABORT + se_cmd fabric stop"). This patch is based on the following two patches: * Bart Van Assche, target: Simplify session shutdown code, February 19, 2015 (https://github.com/bvanassche/linux/commit/8df5463d7d7619f2f1b70cfe5172eaef0aa52815). * Christoph Hellwig, target: Rework session shutdown code, December 7, 2015 (http://thread.gmane.org/gmane.linux.scsi.target.devel/10695). Signed-off-by: Bart Van Assche Reviewed-by: Mike Christie Cc: Hannes Reinecke Cc: Christoph Hellwig Cc: Sagi Grimberg Signed-off-by: Martin K. Petersen

scsi: target: Convert target drivers to use sbitmap

2018-06-20T02:02:25+00:00

The sbitmap and the percpu_ida perform essentially the same task, allocating tags for commands. The sbitmap outperforms the percpu_ida as documented here: https://lkml.org/lkml/2014/4/22/553 The sbitmap interface is a little harder to use, but being able to remove the percpu_ida code and getting better performance justifies the additional complexity. Signed-off-by: Matthew Wilcox Acked-by: Felipe Balbi # f_tcm Reviewed-by: Jens Axboe Signed-off-by: Martin K. Petersen

scsi: target: Abstract tag freeing

2018-06-20T02:02:25+00:00

Introduce target_free_tag() and convert all drivers to use it. Signed-off-by: Matthew Wilcox Reviewed-by: Jens Axboe Signed-off-by: Martin K. Petersen

scsi: target: transport should handle st FM/EOM/ILI reads

2018-05-18T16:22:48+00:00

When a tape drive is exported via LIO using the pscsi module, a read that requests more bytes per block than the tape can supply returns an empty buffer. This is because the pscsi pass-through target module sees the "ILI" illegal length bit set and thinks there is no reason to return the data. This is a long-standing transport issue, since it assumes that no data need be returned under a check condition, which isn't always the case for tape. Add in a check for tape reads with the ILI, EOM, or FM bits set, with a sense code of NO_SENSE, treating such cases as if the read succeeded. The layered tape driver then "does the right thing" when it gets such a response. Signed-off-by: Bodo Stroesser Signed-off-by: Lee Duncan Reviewed-by: Hannes Reinecke Signed-off-by: Martin K. Petersen

target core: add device action configfs files

2018-01-17T02:05:04+00:00

This patch adds a new group of files that are to be used to have the kernel module execution some action. The next patch will have target_core_user use the group/files to be able to block a device and to reset its memory buffer used to pass commands between user/kernel space. This type of file is different from the existing device attributes in that they may be write only and when written to they result in the kernel module executing some function. These need to be separate from the normal device attributes which get/set device values so userspace can continue to loop over all the attribs and get/set them during initialization. Signed-off-by: Mike Christie Signed-off-by: Nicholas Bellinger

target: add SAM_STAT_BUSY sense reason

2018-01-12T23:07:30+00:00

Add SAM_STAT_BUSY sense_reason. The next patch will have target_core_user return this value while it is temporarily blocked and restarting. Signed-off-by: Mike Christie Signed-off-by: Nicholas Bellinger

Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending

2017-11-25T05:19:20+00:00

Pull SCSI target updates from Nicholas Bellinger: "This series is predominantly bug-fixes, with a few small improvements that have been outstanding over the last release cycle. As usual, the associated bug-fixes have CC' tags for stable. Also, things have been particularly quiet wrt new developments the last months, with most folks continuing to focus on stability atop 4.x stable kernels for their respective production configurations. Also at this point, the stable trees have been synced up with mainline. This will continue to be a priority, as production users tend to run exclusively atop stable kernels, a few releases behind mainline. The highlights include: - Fix PR PREEMPT_AND_ABORT null pointer dereference regression in v4.11+ (tangwenji) - Fix OOPs during removing TCMU device (Xiubo Li + Zhang Zhuoyu) - Add netlink command reply supported option for each device (Kenjiro Nakayama) - cxgbit: Abort the TCP connection in case of data out timeout (Varun Prakash) - Fix PR/ALUA file path truncation (David Disseldorp) - Fix double se_cmd completion during ->cmd_time_out (Mike Christie) - Fix QUEUE_FULL + SCSI task attribute handling in 4.1+ (Bryant Ly + nab) - Fix quiese during transport_write_pending_qf endless loop (nab) - Avoid early CMD_T_PRE_EXECUTE failures during ABORT_TASK in 3.14+ (Don White + nab)" * 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (35 commits) tcmu: Add a missing unlock on an error path tcmu: Fix some memory corruption iscsi-target: Fix non-immediate TMR reference leak iscsi-target: Make TASK_REASSIGN use proper se_cmd->cmd_kref target: Avoid early CMD_T_PRE_EXECUTE failures during ABORT_TASK target: Fix quiese during transport_write_pending_qf endless loop target: Fix caw_sem leak in transport_generic_request_failure target: Fix QUEUE_FULL + SCSI task attribute handling iSCSI-target: Use common error handling code in iscsi_decode_text_input() target/iscsi: Detect conn_cmd_list corruption early target/iscsi: Fix a race condition in iscsit_add_reject_from_cmd() target/iscsi: Modify iscsit_do_crypto_hash_buf() prototype target/iscsi: Fix endianness in an error message target/iscsi: Use min() in iscsit_dump_data_payload() instead of open-coding it target/iscsi: Define OFFLOAD_BUF_SIZE once target: Inline transport_put_cmd() target: Suppress gcc 7 fallthrough warnings target: Move a declaration of a global variable into a header file tcmu: fix double se_cmd completion target: return SAM_STAT_TASK_SET_FULL for TCM_OUT_OF_RESOURCES ...