kernel/linux.git/drivers/scsi/libiscsi.c, branch v6.18.22

scsi: libiscsi: Initialize iscsi_conn->dd_data only if memory is allocated

2025-07-22T03:48:36+00:00

In case of an ib_fast_reg_mr allocation failure during iSER setup, the machine hits a panic because iscsi_conn->dd_data is initialized unconditionally, even when no memory is allocated (dd_size == 0). This leads invalid pointer dereference during connection teardown. Fix by setting iscsi_conn->dd_data only if memory is actually allocated. Panic trace: ------------ iser: iser_create_fastreg_desc: Failed to allocate ib_fast_reg_mr err=-12 iser: iser_alloc_rx_descriptors: failed allocating rx descriptors / data buffers BUG: unable to handle page fault for address: fffffffffffffff8 RIP: 0010:swake_up_locked.part.5+0xa/0x40 Call Trace: complete+0x31/0x40 iscsi_iser_conn_stop+0x88/0xb0 [ib_iser] iscsi_stop_conn+0x66/0xc0 [scsi_transport_iscsi] iscsi_if_stop_conn+0x14a/0x150 [scsi_transport_iscsi] iscsi_if_rx+0x1135/0x1834 [scsi_transport_iscsi] ? netlink_lookup+0x12f/0x1b0 ? netlink_deliver_tap+0x2c/0x200 netlink_unicast+0x1ab/0x280 netlink_sendmsg+0x257/0x4f0 ? _copy_from_user+0x29/0x60 sock_sendmsg+0x5f/0x70 Signed-off-by: Showrya M N Signed-off-by: Potnuri Bharat Teja Link: https://lore.kernel.org/r/20250627112329.19763-1-showrya@chelsio.com Reviewed-by: Chris Leech Signed-off-by: Martin K. Petersen

treewide, timers: Rename from_timer() to timer_container_of()

2025-06-08T07:07:37+00:00

Move this API to the canonical timer_*() namespace. [ tglx: Redone against pre rc1 ] Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/aB2X0jCKQO56WdMt@gmail.com

treewide: Switch/rename to timer_delete[_sync]()

2025-04-05T08:30:12+00:00

timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree over and remove the historical wrapper inlines. Conversion was done with coccinelle plus manual fixups where necessary. Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar

move asm/unaligned.h to linux/unaligned.h

2024-10-02T21:23:23+00:00

asm/unaligned.h is always an include of asm-generic/unaligned.h; might as well move that thing to linux/unaligned.h and include that - there's nothing arch-specific in that header. auto-generated by the following: for i in `git grep -l -w asm/unaligned.h`; do sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i done for i in `git grep -l -w asm-generic/unaligned.h`; do sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i done git mv include/asm-generic/unaligned.h include/linux/unaligned.h git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h

scsi: iscsi: Declare SCSI host template const

2023-03-24T23:19:57+00:00

Make it explicit that the SCSI host template is not modified. Reviewed-by: Mike Christie Signed-off-by: Bart Van Assche Link: https://lore.kernel.org/r/20230322195515.1267197-50-bvanassche@acm.org Signed-off-by: Martin K. Petersen

scsi: iscsi_tcp: Fix UAF during logout when accessing the shost ipaddress

2023-01-19T00:14:56+00:00

Bug report and analysis from Ding Hui. During iSCSI session logout, if another task accesses the shost ipaddress attr, we can get a KASAN UAF report like this: [ 276.942144] BUG: KASAN: use-after-free in _raw_spin_lock_bh+0x78/0xe0 [ 276.942535] Write of size 4 at addr ffff8881053b45b8 by task cat/4088 [ 276.943511] CPU: 2 PID: 4088 Comm: cat Tainted: G E 6.1.0-rc8+ #3 [ 276.943997] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020 [ 276.944470] Call Trace: [ 276.944943] [ 276.945397] dump_stack_lvl+0x34/0x48 [ 276.945887] print_address_description.constprop.0+0x86/0x1e7 [ 276.946421] print_report+0x36/0x4f [ 276.947358] kasan_report+0xad/0x130 [ 276.948234] kasan_check_range+0x35/0x1c0 [ 276.948674] _raw_spin_lock_bh+0x78/0xe0 [ 276.949989] iscsi_sw_tcp_host_get_param+0xad/0x2e0 [iscsi_tcp] [ 276.951765] show_host_param_ISCSI_HOST_PARAM_IPADDRESS+0xe9/0x130 [scsi_transport_iscsi] [ 276.952185] dev_attr_show+0x3f/0x80 [ 276.953005] sysfs_kf_seq_show+0x1fb/0x3e0 [ 276.953401] seq_read_iter+0x402/0x1020 [ 276.954260] vfs_read+0x532/0x7b0 [ 276.955113] ksys_read+0xed/0x1c0 [ 276.955952] do_syscall_64+0x38/0x90 [ 276.956347] entry_SYSCALL_64_after_hwframe+0x63/0xcd [ 276.956769] RIP: 0033:0x7f5d3a679222 [ 276.957161] Code: c0 e9 b2 fe ff ff 50 48 8d 3d 32 c0 0b 00 e8 a5 fe 01 00 0f 1f 44 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 0f 05 <48> 3d 00 f0 ff ff 77 56 c3 0f 1f 44 00 00 48 83 ec 28 48 89 54 24 [ 276.958009] RSP: 002b:00007ffc864d16a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 276.958431] RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007f5d3a679222 [ 276.958857] RDX: 0000000000020000 RSI: 00007f5d3a4fe000 RDI: 0000000000000003 [ 276.959281] RBP: 00007f5d3a4fe000 R08: 00000000ffffffff R09: 0000000000000000 [ 276.959682] R10: 0000000000000022 R11: 0000000000000246 R12: 0000000000020000 [ 276.960126] R13: 0000000000000003 R14: 0000000000000000 R15: 0000557a26dada58 [ 276.960536] [ 276.961357] Allocated by task 2209: [ 276.961756] kasan_save_stack+0x1e/0x40 [ 276.962170] kasan_set_track+0x21/0x30 [ 276.962557] __kasan_kmalloc+0x7e/0x90 [ 276.962923] __kmalloc+0x5b/0x140 [ 276.963308] iscsi_alloc_session+0x28/0x840 [scsi_transport_iscsi] [ 276.963712] iscsi_session_setup+0xda/0xba0 [libiscsi] [ 276.964078] iscsi_sw_tcp_session_create+0x1fd/0x330 [iscsi_tcp] [ 276.964431] iscsi_if_create_session.isra.0+0x50/0x260 [scsi_transport_iscsi] [ 276.964793] iscsi_if_recv_msg+0xc5a/0x2660 [scsi_transport_iscsi] [ 276.965153] iscsi_if_rx+0x198/0x4b0 [scsi_transport_iscsi] [ 276.965546] netlink_unicast+0x4d5/0x7b0 [ 276.965905] netlink_sendmsg+0x78d/0xc30 [ 276.966236] sock_sendmsg+0xe5/0x120 [ 276.966576] ____sys_sendmsg+0x5fe/0x860 [ 276.966923] ___sys_sendmsg+0xe0/0x170 [ 276.967300] __sys_sendmsg+0xc8/0x170 [ 276.967666] do_syscall_64+0x38/0x90 [ 276.968028] entry_SYSCALL_64_after_hwframe+0x63/0xcd [ 276.968773] Freed by task 2209: [ 276.969111] kasan_save_stack+0x1e/0x40 [ 276.969449] kasan_set_track+0x21/0x30 [ 276.969789] kasan_save_free_info+0x2a/0x50 [ 276.970146] __kasan_slab_free+0x106/0x190 [ 276.970470] __kmem_cache_free+0x133/0x270 [ 276.970816] device_release+0x98/0x210 [ 276.971145] kobject_cleanup+0x101/0x360 [ 276.971462] iscsi_session_teardown+0x3fb/0x530 [libiscsi] [ 276.971775] iscsi_sw_tcp_session_destroy+0xd8/0x130 [iscsi_tcp] [ 276.972143] iscsi_if_recv_msg+0x1bf1/0x2660 [scsi_transport_iscsi] [ 276.972485] iscsi_if_rx+0x198/0x4b0 [scsi_transport_iscsi] [ 276.972808] netlink_unicast+0x4d5/0x7b0 [ 276.973201] netlink_sendmsg+0x78d/0xc30 [ 276.973544] sock_sendmsg+0xe5/0x120 [ 276.973864] ____sys_sendmsg+0x5fe/0x860 [ 276.974248] ___sys_sendmsg+0xe0/0x170 [ 276.974583] __sys_sendmsg+0xc8/0x170 [ 276.974891] do_syscall_64+0x38/0x90 [ 276.975216] entry_SYSCALL_64_after_hwframe+0x63/0xcd We can easily reproduce by two tasks: 1. while :; do iscsiadm -m node --login; iscsiadm -m node --logout; done 2. while :; do cat \ /sys/devices/platform/host*/iscsi_host/host*/ipaddress; done iscsid | cat --------------------------------+--------------------------------------- |- iscsi_sw_tcp_session_destroy | |- iscsi_session_teardown | |- device_release | |- iscsi_session_release ||- dev_attr_show |- kfree | |- show_host_param_ | ISCSI_HOST_PARAM_IPADDRESS | |- iscsi_sw_tcp_host_get_param | |- r/w tcp_sw_host->session (UAF) |- iscsi_host_remove | |- iscsi_host_free | Fix the above bug by splitting the session removal into 2 parts: 1. removal from iSCSI class which includes sysfs and removal from host tracking. 2. freeing of session. During iscsi_tcp host and session removal we can remove the session from sysfs then remove the host from sysfs. At this point we know userspace is not accessing the kernel via sysfs so we can free the session and host. Link: https://lore.kernel.org/r/20230117193937.21244-2-michael.christie@oracle.com Signed-off-by: Mike Christie Reviewed-by: Lee Duncan Acked-by: Ding Hui Signed-off-by: Martin K. Petersen

scsi: core: Change the return type of .eh_timed_out()

2022-10-22T03:25:59+00:00

Commit 6600593cbd93 ("block: rename BLK_EH_NOT_HANDLED to BLK_EH_DONE") made it impossible for .eh_timed_out() implementations to call scsi_done() without causing a crash. Restore support for SCSI timeout handlers to call scsi_done() as follows: * Change all .eh_timed_out() handlers as follows: - Change the return type into enum scsi_timeout_action. - Change BLK_EH_RESET_TIMER into SCSI_EH_RESET_TIMER. - Change BLK_EH_DONE into SCSI_EH_NOT_HANDLED. * In scsi_timeout(), convert the SCSI_EH_* values into BLK_EH_* values. Reviewed-by: Lee Duncan Cc: Christoph Hellwig Cc: Ming Lei Cc: John Garry Cc: Mike Christie Cc: Hannes Reinecke Signed-off-by: Bart Van Assche Link: https://lore.kernel.org/r/20221018202958.1902564-3-bvanassche@acm.org Reviewed-by: Mike Christie Signed-off-by: Martin K. Petersen

scsi: libiscsi: Improve conn_send_pdu API

2022-06-22T01:19:23+00:00

The conn_send_pdu API is evil in that it returns a pointer to an iscsi_task, but that task might have been freed already so you can't touch it. This patch splits the task allocation and transmission, so functions like iscsi_send_nopout() can access the task before its sent and do whatever bookkeeping is needed before it is sent. Link: https://lore.kernel.org/r/20220616224557.115234-10-michael.christie@oracle.com Reviewed-by: Lee Duncan Signed-off-by: Mike Christie Signed-off-by: Martin K. Petersen

scsi: iscsi: Try to avoid taking back_lock in xmit path

2022-06-22T01:19:23+00:00

We need the back lock when freeing a task, so we hold it when calling __iscsi_put_task() from the completion path to make it easier and to avoid having to retake it in that path. For iscsi_put_task() we just grabbed it while also doing the decrement on the refcount but it's only really needed if the refcount is zero and we free the task. This modifies iscsi_put_task() to just take the lock when needed then has the xmit path use it. Normally we will then not take the back lock from the xmit path. It will only be rare cases where the network is so fast that we get a response right after we send the header/data. Link: https://lore.kernel.org/r/20220616224557.115234-9-michael.christie@oracle.com Reviewed-by: Lee Duncan Signed-off-by: Mike Christie Signed-off-by: Martin K. Petersen

scsi: iscsi: Remove iscsi_get_task back_lock requirement

2022-06-22T01:19:23+00:00

We currently require that the back_lock is held when calling the functions that manipulate the iscsi_task refcount. The only reason for this is to handle races where we are handling SCSI-ml EH callbacks and the cmd is completing at the same time the normal completion path is running, and we can't return from the EH callback until the driver has stopped accessing the cmd. Holding the back_lock while also accessing the task->state made it simple to check that a cmd is completing and also get/put a refcount at the same time, and at the time we were not as concerned about performance. The problem is that we don't want to take the back_lock from the xmit path for normal I/O since it causes contention with the completion path if the user has chosen to try and split those paths on different CPUs (in this case abusing the CPUs and ignoring caching improves perf for some uses). Begins to remove the back_lock requirement for iscsi_get/put_task by removing the requirement for the get path. Instead of always holding the back_lock we detect if something has done the last put and is about to call iscsi_free_task(). A subsequent commit will then allow iSCSI code to do the last put on a task and only grab the back_lock if the refcount is now zero and it's going to call iscsi_free_task(). Link: https://lore.kernel.org/r/20220616224557.115234-8-michael.christie@oracle.com Reviewed-by: Lee Duncan Signed-off-by: Mike Christie Signed-off-by: Martin K. Petersen