user/sven/linux.git/drivers/target, branch v5.4.76

scsi: target: tcmu: Fix warning: 'page' may be used uninitialized

2020-10-29T08:57:44Z

[ Upstream commit 61741d8699e1fc764a309ebd20211bb1cb193110 ] Corrects drivers/target/target_core_user.c:688:6: warning: 'page' may be used uninitialized. Link: https://lore.kernel.org/r/20200924001920.43594-1-john.p.donnelly@oracle.com Fixes: 3c58f737231e ("scsi: target: tcmu: Optimize use of flush_dcache_page") Cc: Mike Christie Acked-by: Mike Christie Signed-off-by: John Donnelly Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin

scsi: target: iscsi: Fix hang in iscsit_access_np() when getting tpg->np_login_sem

2020-09-17T11:47:53Z

commit ed43ffea78dcc97db3f561da834f1a49c8961e33 upstream. The iSCSI target login thread might get stuck with the following stack: cat /proc/`pidof iscsi_np`/stack [<0>] down_interruptible+0x42/0x50 [<0>] iscsit_access_np+0xe3/0x167 [<0>] iscsi_target_locate_portal+0x695/0x8ac [<0>] __iscsi_target_login_thread+0x855/0xb82 [<0>] iscsi_target_login_thread+0x2f/0x5a [<0>] kthread+0xfa/0x130 [<0>] ret_from_fork+0x1f/0x30 This can be reproduced via the following steps: 1. Initiator A tries to log in to iqn1-tpg1 on port 3260. After finishing PDU exchange in the login thread and before the negotiation is finished the the network link goes down. At this point A has not finished login and tpg->np_login_sem is held. 2. Initiator B tries to log in to iqn2-tpg1 on port 3260. After finishing PDU exchange in the login thread the target expects to process remaining login PDUs in workqueue context. 3. Initiator A' tries to log in to iqn1-tpg1 on port 3260 from a new socket. A' will wait for tpg->np_login_sem with np->np_login_timer loaded to wait for at most 15 seconds. The lock is held by A so A' eventually times out. 4. Before A' got timeout initiator B gets negotiation failed and calls iscsi_target_login_drop()->iscsi_target_login_sess_out(). The np->np_login_timer is canceled and initiator A' will hang forever. Because A' is now in the login thread, no new login requests can be serviced. Fix this by moving iscsi_stop_login_thread_timer() out of iscsi_target_login_sess_out(). Also remove iscsi_np parameter from iscsi_target_login_sess_out(). Link: https://lore.kernel.org/r/20200729130343.24976-1-houpu@bytedance.com Cc: stable@vger.kernel.org Reviewed-by: Mike Christie Signed-off-by: Hou Pu Signed-off-by: Martin K. Petersen Signed-off-by: Greg Kroah-Hartman

scsi: target: iscsi: Fix data digest calculation

2020-09-17T11:47:52Z

commit 5528d03183fe5243416c706f64b1faa518b05130 upstream. Current code does not consider 'page_off' in data digest calculation. To fix this, add a local variable 'first_sg' and set first_sg.offset to sg->offset + page_off. Link: https://lore.kernel.org/r/1598358910-3052-1-git-send-email-varun@chelsio.com Fixes: e48354ce078c ("iscsi-target: Add iSCSI fabric support for target v4.1") Cc: Reviewed-by: Mike Christie Signed-off-by: Varun Prakash Signed-off-by: Martin K. Petersen Signed-off-by: Greg Kroah-Hartman

scsi: target: tcmu: Optimize use of flush_dcache_page

2020-09-05T09:22:51Z

commit 3c58f737231e2c8cbf543a09d84d8c8e80e05e43 upstream. (scatter|gather)_data_area() need to flush dcache after writing data to or before reading data from a page in uio data area. The two routines are able to handle data transfer to/from such a page in fragments and flush the cache after each fragment was copied by calling the wrapper tcmu_flush_dcache_range(). That means: 1) flush_dcache_page() can be called multiple times for the same page. 2) Calling flush_dcache_page() indirectly using the wrapper does not make sense, because each call of the wrapper is for one single page only and the calling routine already has the correct page pointer. Change (scatter|gather)_data_area() such that, instead of calling tcmu_flush_dcache_range() before/after each memcpy, it now calls flush_dcache_page() before unmapping a page (when writing is complete for that page) or after mapping a page (when starting to read the page). After this change only calls to tcmu_flush_dcache_range() for addresses in vmalloc'ed command ring are left over. The patch was tested on ARM with kernel 4.19.118 and 5.7.2 Link: https://lore.kernel.org/r/20200618131632.32748-2-bstroesser@ts.fujitsu.com Tested-by: JiangYu Tested-by: Daniel Meyerholt Acked-by: Mike Christie Signed-off-by: Bodo Stroesser Signed-off-by: Martin K. Petersen Signed-off-by: Greg Kroah-Hartman

scsi: target: tcmu: Fix size in calls to tcmu_flush_dcache_range

2020-09-05T09:22:51Z

commit 8c4e0f212398cdd1eb4310a5981d06a723cdd24f upstream. 1) If remaining ring space before the end of the ring is smaller then the next cmd to write, tcmu writes a padding entry which fills the remaining space at the end of the ring. Then tcmu calls tcmu_flush_dcache_range() with the size of struct tcmu_cmd_entry as data length to flush. If the space filled by the padding was smaller then tcmu_cmd_entry, tcmu_flush_dcache_range() is called for an address range reaching behind the end of the vmalloc'ed ring. tcmu_flush_dcache_range() in a loop calls flush_dcache_page(virt_to_page(start)); for every page being part of the range. On x86 the line is optimized out by the compiler, as flush_dcache_page() is empty on x86. But I assume the above can cause trouble on other architectures that really have a flush_dcache_page(). For paddings only the header part of an entry is relevant due to alignment rules the header always fits in the remaining space, if padding is needed. So tcmu_flush_dcache_range() can safely be called with sizeof(entry->hdr) as the length here. 2) After it has written a command to cmd ring, tcmu calls tcmu_flush_dcache_range() using the size of a struct tcmu_cmd_entry as data length to flush. But if a command needs many iovecs, the real size of the command may be bigger then tcmu_cmd_entry, so a part of the written command is not flushed then. Link: https://lore.kernel.org/r/20200528193108.9085-1-bstroesser@ts.fujitsu.com Acked-by: Mike Christie Signed-off-by: Bodo Stroesser Signed-off-by: Martin K. Petersen Signed-off-by: Greg Kroah-Hartman

scsi: target: Fix xcopy sess release leak

2020-09-03T09:26:44Z

[ Upstream commit 3c006c7d23aac928279f7cbe83bbac4361255d53 ] transport_init_session can allocate memory via percpu_ref_init, and target_xcopy_release_pt never frees it. This adds a transport_uninit_session function to handle cleanup of resources allocated in the init function. Link: https://lore.kernel.org/r/1593654203-12442-3-git-send-email-michael.christie@oracle.com Signed-off-by: Mike Christie Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin

scsi: target: tcmu: Fix crash on ARM during cmd completion

2020-09-03T09:26:43Z

[ Upstream commit 5a0c256d96f020e4771f6fd5524b80f89a2d3132 ] If tcmu_handle_completions() has to process a padding shorter than sizeof(struct tcmu_cmd_entry), the current call to tcmu_flush_dcache_range() with sizeof(struct tcmu_cmd_entry) as length param is wrong and causes crashes on e.g. ARM, because tcmu_flush_dcache_range() in this case calls flush_dcache_page(vmalloc_to_page(start)); with start being an invalid address above the end of the vmalloc'ed area. The fix is to use the minimum of remaining ring space and sizeof(struct tcmu_cmd_entry) as the length param. The patch was tested on kernel 4.19.118. See https://bugzilla.kernel.org/show_bug.cgi?id=208045#c10 Link: https://lore.kernel.org/r/20200629093756.8947-1-bstroesser@ts.fujitsu.com Tested-by: JiangYu Acked-by: Mike Christie Signed-off-by: Bodo Stroesser Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin

scsi: target: tcmu: Fix crash in tcmu_flush_dcache_range on ARM

2020-08-26T08:40:54Z

[ Upstream commit 3145550a7f8b08356c8ff29feaa6c56aca12901d ] This patch fixes the following crash (see https://bugzilla.kernel.org/show_bug.cgi?id=208045) Process iscsi_trx (pid: 7496, stack limit = 0x0000000010dd111a) CPU: 0 PID: 7496 Comm: iscsi_trx Not tainted 4.19.118-0419118-generic #202004230533 Hardware name: Greatwall QingTian DF720/F601, BIOS 601FBE20 Sep 26 2019 pstate: 80400005 (Nzcv daif +PAN -UAO) pc : flush_dcache_page+0x18/0x40 lr : is_ring_space_avail+0x68/0x2f8 [target_core_user] sp : ffff000015123a80 x29: ffff000015123a80 x28: 0000000000000000 x27: 0000000000001000 x26: ffff000023ea5000 x25: ffffcfa25bbe08b8 x24: 0000000000000078 x23: ffff7e0000000000 x22: ffff000023ea5001 x21: ffffcfa24b79c000 x20: 0000000000000fff x19: ffff7e00008fa940 x18: 0000000000000000 x17: 0000000000000000 x16: ffff2d047e709138 x15: 0000000000000000 x14: 0000000000000000 x13: 0000000000000000 x12: ffff2d047fbd0a40 x11: 0000000000000000 x10: 0000000000000030 x9 : 0000000000000000 x8 : ffffc9a254820a00 x7 : 00000000000013b0 x6 : 000000000000003f x5 : 0000000000000040 x4 : ffffcfa25bbe08e8 x3 : 0000000000001000 x2 : 0000000000000078 x1 : ffffcfa25bbe08b8 x0 : ffff2d040bc88a18 Call trace: flush_dcache_page+0x18/0x40 is_ring_space_avail+0x68/0x2f8 [target_core_user] queue_cmd_ring+0x1f8/0x680 [target_core_user] tcmu_queue_cmd+0xe4/0x158 [target_core_user] __target_execute_cmd+0x30/0xf0 [target_core_mod] target_execute_cmd+0x294/0x390 [target_core_mod] transport_generic_new_cmd+0x1e8/0x358 [target_core_mod] transport_handle_cdb_direct+0x50/0xb0 [target_core_mod] iscsit_execute_cmd+0x2b4/0x350 [iscsi_target_mod] iscsit_sequence_cmd+0xd8/0x1d8 [iscsi_target_mod] iscsit_process_scsi_cmd+0xac/0xf8 [iscsi_target_mod] iscsit_get_rx_pdu+0x404/0xd00 [iscsi_target_mod] iscsi_target_rx_thread+0xb8/0x130 [iscsi_target_mod] kthread+0x130/0x138 ret_from_fork+0x10/0x18 Code: f9000bf3 aa0003f3 aa1e03e0 d503201f (f9400260) ---[ end trace 1e451c73f4266776 ]--- The solution is based on patch: "scsi: target: tcmu: Optimize use of flush_dcache_page" which restricts the use of tcmu_flush_dcache_range() to addresses from vmalloc'ed areas only. This patch now replaces the virt_to_page() call in tcmu_flush_dcache_range() - which is wrong for vmalloced addrs - by vmalloc_to_page(). The patch was tested on ARM with kernel 4.19.118 and 5.7.2 Link: https://lore.kernel.org/r/20200618131632.32748-3-bstroesser@ts.fujitsu.com Tested-by: JiangYu Tested-by: Daniel Meyerholt Acked-by: Mike Christie Signed-off-by: Bodo Stroesser Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin

scsi: target: tcmu: Fix a use after free in tcmu_check_expired_queue_cmd()

2020-06-24T15:50:34Z

[ Upstream commit 9d7464b18892332e35ff37f0b024429a1a9835e6 ] The pr_debug() dereferences "cmd" after we already freed it by calling tcmu_free_cmd(cmd). The debug printk needs to be done earlier. Link: https://lore.kernel.org/r/20200523101129.GB98132@mwanda Fixes: 61fb24822166 ("scsi: target: tcmu: Userspace must not complete queued commands") Reviewed-by: Mike Christie Reviewed-by: David Disseldorp Signed-off-by: Dan Carpenter Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin

scsi: target: tcmu: Userspace must not complete queued commands

2020-06-24T15:50:30Z

[ Upstream commit 61fb2482216679b9e1e797440c148bb143a5040a ] When tcmu queues a new command - no matter whether in command ring or in qfull_queue - a cmd_id from IDR udev->commands is assigned to the command. If userspace sends a wrong command completion containing the cmd_id of a command on the qfull_queue, tcmu_handle_completions() finds the command in the IDR and calls tcmu_handle_completion() for it. This might do some nasty things because commands in qfull_queue do not have a valid dbi list. To fix this bug, we no longer add queued commands to the idr. Instead the cmd_id is assign when a command is written to the command ring. Due to this change I had to adapt the source code at several places where up to now an idr_for_each had been done. [mkp: fix checkpatch warnings] Link: https://lore.kernel.org/r/20200518164833.12775-1-bstroesser@ts.fujitsu.com Acked-by: Mike Christie Signed-off-by: Bodo Stroesser Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin