kernel.git/drivers/scsi/sg.c, branch linux-5.4.y

scsi: sg: Do not sleep in atomic context

2025-12-03T11:45:20Z

commit 90449f2d1e1f020835cba5417234636937dd657e upstream. sg_finish_rem_req() calls blk_rq_unmap_user(). The latter function may sleep. Hence, call sg_finish_rem_req() with interrupts enabled instead of disabled. Reported-by: syzbot+c01f8e6e73f20459912e@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-scsi/691560c4.a70a0220.3124cb.001a.GAE@google.com/ Cc: Hannes Reinecke Cc: stable@vger.kernel.org Fixes: 97d27b0dd015 ("scsi: sg: close race condition in sg_remove_sfp_usercontext()") Signed-off-by: Bart Van Assche Link: https://patch.msgid.link/20251113181643.1108973-1-bvanassche@acm.org Signed-off-by: Martin K. Petersen Signed-off-by: Greg Kroah-Hartman

scsi: sg: Fix slab-use-after-free read in sg_release()

2025-02-01T17:18:51Z

commit f10593ad9bc36921f623361c9e3dd96bd52d85ee upstream. Fix a use-after-free bug in sg_release(), detected by syzbot with KASAN: BUG: KASAN: slab-use-after-free in lock_release+0x151/0xa30 kernel/locking/lockdep.c:5838 __mutex_unlock_slowpath+0xe2/0x750 kernel/locking/mutex.c:912 sg_release+0x1f4/0x2e0 drivers/scsi/sg.c:407 In sg_release(), the function kref_put(&sfp->f_ref, sg_remove_sfp) is called before releasing the open_rel_lock mutex. The kref_put() call may decrement the reference count of sfp to zero, triggering its cleanup through sg_remove_sfp(). This cleanup includes scheduling deferred work via sg_remove_sfp_usercontext(), which ultimately frees sfp. After kref_put(), sg_release() continues to unlock open_rel_lock and may reference sfp or sdp. If sfp has already been freed, this results in a slab-use-after-free error. Move the kref_put(&sfp->f_ref, sg_remove_sfp) call after unlocking the open_rel_lock mutex. This ensures: - No references to sfp or sdp occur after the reference count is decremented. - Cleanup functions such as sg_remove_sfp() and sg_remove_sfp_usercontext() can safely execute without impacting the mutex handling in sg_release(). The fix has been tested and validated by syzbot. This patch closes the bug reported at the following syzkaller link and ensures proper sequencing of resource cleanup and mutex operations, eliminating the risk of use-after-free errors in sg_release(). Reported-by: syzbot+7efb5850a17ba6ce098b@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=7efb5850a17ba6ce098b Tested-by: syzbot+7efb5850a17ba6ce098b@syzkaller.appspotmail.com Fixes: cc833acbee9d ("sg: O_EXCL and other lock handling") Signed-off-by: Suraj Sonawane Link: https://lore.kernel.org/r/20241120125944.88095-1-surajsonawane0215@gmail.com Reviewed-by: Bart Van Assche Signed-off-by: Martin K. Petersen Signed-off-by: BRUNO VERNAY Signed-off-by: Hugo SIMELIERE Signed-off-by: Greg Kroah-Hartman

scsi: sg: Allow waiting for commands to complete on removed device

2022-08-25T09:18:17Z

commit 3455607fd7be10b449f5135c00dc306b85dc0d21 upstream. When a SCSI device is removed while in active use, currently sg will immediately return -ENODEV on any attempt to wait for active commands that were sent before the removal. This is problematic for commands that use SG_FLAG_DIRECT_IO since the data buffer may still be in use by the kernel when userspace frees or reuses it after getting ENODEV, leading to corrupted userspace memory (in the case of READ-type commands) or corrupted data being sent to the device (in the case of WRITE-type commands). This has been seen in practice when logging out of a iscsi_tcp session, where the iSCSI driver may still be processing commands after the device has been marked for removal. Change the policy to allow userspace to wait for active sg commands even when the device is being removed. Return -ENODEV only when there are no more responses to read. Link: https://lore.kernel.org/r/5ebea46f-fe83-2d0b-233d-d0dcb362dd0a@cybernetics.com Cc: Acked-by: Douglas Gilbert Signed-off-by: Tony Battersby Signed-off-by: Martin K. Petersen Signed-off-by: Greg Kroah-Hartman

scsi: sg: add sg_remove_request in sg_write

2020-05-20T06:20:07Z

commit 83c6f2390040f188cc25b270b4befeb5628c1aee upstream. If the __copy_from_user function failed we need to call sg_remove_request in sg_write. Link: https://lore.kernel.org/r/610618d9-e983-fd56-ed0f-639428343af7@huawei.com Acked-by: Douglas Gilbert Signed-off-by: Wu Bo Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin [groeck: Backport to v5.4.y and older kernels] Signed-off-by: Guenter Roeck Signed-off-by: Greg Kroah-Hartman

scsi: sg: add sg_remove_request in sg_common_write

2020-04-23T08:36:16Z

commit 849f8583e955dbe3a1806e03ecacd5e71cce0a08 upstream. If the dxfer_len is greater than 256M then the request is invalid and we need to call sg_remove_request in sg_common_write. Link: https://lore.kernel.org/r/1586777361-17339-1-git-send-email-huawei.libin@huawei.com Fixes: f930c7043663 ("scsi: sg: only check for dxfer_len greater than 256M") Acked-by: Douglas Gilbert Signed-off-by: Li Bin Signed-off-by: Martin K. Petersen Signed-off-by: Greg Kroah-Hartman

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 45

2019-05-24T15:27:12Z

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 11 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Kate Stewart Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190520170858.370933192@linutronix.de Signed-off-by: Greg Kroah-Hartman

Remove 'type' argument from access_ok() function

2019-01-04T02:57:57Z

Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument of the user address range verification function since we got rid of the old racy i386-only code to walk page tables by hand. It existed because the original 80386 would not honor the write protect bit when in kernel mode, so you had to do COW by hand before doing any user access. But we haven't supported that in a long time, and these days the 'type' argument is a purely historical artifact. A discussion about extending 'user_access_begin()' to do the range checking resulted this patch, because there is no way we're going to move the old VERIFY_xyz interface to that model. And it's best done at the end of the merge window when I've done most of my merges, so let's just get this done once and for all. This patch was mostly done with a sed-script, with manual fix-ups for the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form. There were a couple of notable cases: - csky still had the old "verify_area()" name as an alias. - the iter_iov code had magical hardcoded knowledge of the actual values of VERIFY_{READ,WRITE} (not that they mattered, since nothing really used it) - microblaze used the type argument for a debug printout but other than those oddities this should be a total no-op patch. I tried to fix up all architectures, did fairly extensive grepping for access_ok() uses, and the changes are trivial, but I may have missed something. Any missed conversion should be trivially fixable, though. Signed-off-by: Linus Torvalds

block: remove __blk_put_request()

2018-11-07T20:42:32Z

Now there's no difference between blk_put_request() and __blk_put_request() anymore, get rid of the underscore version and convert the few callers. Reviewed-by: Hannes Reinecke Tested-by: Ming Lei Reviewed-by: Omar Sandoval Signed-off-by: Jens Axboe

scsi: sg: remove bad blk_end_request_all() call

2018-10-16T21:49:57Z

We just need to free the request here. Additionally, this is currently wrong for a queue that's using MQ currently, it'll crash. Cc: Doug Gilbert Cc: linux-scsi@vger.kernel.org Signed-off-by: Jens Axboe Acked-by: Douglas Gilbert Signed-off-by: Martin K. Petersen

Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

2018-08-16T05:06:26Z

Pull SCSI updates from James Bottomley: "This is mostly updates to the usual drivers: mpt3sas, lpfc, qla2xxx, hisi_sas, smartpqi, megaraid_sas, arcmsr. In addition, with the continuing absence of Nic we have target updates for tcmu and target core (all with reviews and acks). The biggest observable change is going to be that we're (again) trying to switch to mulitqueue as the default (a user can still override the setting on the kernel command line). Other major core stuff is the removal of the remaining Microchannel drivers, an update of the internal timers and some reworks of completion and result handling" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (203 commits) scsi: core: use blk_mq_run_hw_queues in scsi_kick_queue scsi: ufs: remove unnecessary query(DM) UPIU trace scsi: qla2xxx: Fix issue reported by static checker for qla2x00_els_dcmd2_sp_done() scsi: aacraid: Spelling fix in comment scsi: mpt3sas: Fix calltrace observed while running IO & reset scsi: aic94xx: fix an error code in aic94xx_init() scsi: st: remove redundant pointer STbuffer scsi: qla2xxx: Update driver version to 10.00.00.08-k scsi: qla2xxx: Migrate NVME N2N handling into state machine scsi: qla2xxx: Save frame payload size from ICB scsi: qla2xxx: Fix stalled relogin scsi: qla2xxx: Fix race between switch cmd completion and timeout scsi: qla2xxx: Fix Management Server NPort handle reservation logic scsi: qla2xxx: Flush mailbox commands on chip reset scsi: qla2xxx: Fix unintended Logout scsi: qla2xxx: Fix session state stuck in Get Port DB scsi: qla2xxx: Fix redundant fc_rport registration scsi: qla2xxx: Silent erroneous message scsi: qla2xxx: Prevent sysfs access when chip is down scsi: qla2xxx: Add longer window for chip reset ...