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2018-08-06scsi: sg: fix minor memory leak in error pathTony Battersby
commit c170e5a8d222537e98aa8d4fddb667ff7a2ee114 upstream. Fix a minor memory leak when there is an error opening a /dev/sg device. Fixes: cc833acbee9d ("sg: O_EXCL and other lock handling") Cc: <stable@vger.kernel.org> Reviewed-by: Ewan D. Milne <emilne@redhat.com> Signed-off-by: Tony Battersby <tonyb@cybernetics.com> Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-11scsi: sg: mitigate read/write abuseJann Horn
commit 26b5b874aff5659a7e26e5b1997e3df2c41fa7fd upstream. As Al Viro noted in commit 128394eff343 ("sg_write()/bsg_write() is not fit to be called under KERNEL_DS"), sg improperly accesses userspace memory outside the provided buffer, permitting kernel memory corruption via splice(). But it doesn't just do it on ->write(), also on ->read(). As a band-aid, make sure that the ->read() and ->write() handlers can not be called in weird contexts (kernel context or credentials different from file opener), like for ib_safe_file_access(). If someone needs to use these interfaces from different security contexts, a new interface should be written that goes through the ->ioctl() handler. I've mostly copypasted ib_safe_file_access() over as sg_safe_file_access() because I couldn't find a good common header - please tell me if you know a better way. [mkp: s/_safe_/_check_/] Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: <stable@vger.kernel.org> Signed-off-by: Jann Horn <jannh@google.com> Acked-by: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-26scsi: sg: allocate with __GFP_ZERO in sg_build_indirect()Alexander Potapenko
commit a45b599ad808c3c982fdcdc12b0b8611c2f92824 upstream. This shall help avoid copying uninitialized memory to the userspace when calling ioctl(fd, SG_IO) with an empty command. Reported-by: syzbot+7d26fc1eea198488deab@syzkaller.appspotmail.com Cc: stable@vger.kernel.org Signed-off-by: Alexander Potapenko <glider@google.com> Acked-by: Douglas Gilbert <dgilbert@interlog.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-31scsi: sg: don't return bogus Sg_requestsJohannes Thumshirn
commit 48ae8484e9fc324b4968d33c585e54bc98e44d61 upstream. If the list search in sg_get_rq_mark() fails to find a valid request, we return a bogus element. This then can later lead to a GPF in sg_remove_scat(). So don't return bogus Sg_requests in sg_get_rq_mark() but NULL in case the list search doesn't find a valid request. Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Reported-by: Andrey Konovalov <andreyknvl@google.com> Cc: Hannes Reinecke <hare@suse.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Doug Gilbert <dgilbert@interlog.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Acked-by: Doug Gilbert <dgilbert@interlog.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Cc: Tony Battersby <tonyb@cybernetics.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-22scsi: sg: only check for dxfer_len greater than 256MJohannes Thumshirn
commit f930c7043663188429cd9b254e9d761edfc101ce upstream. Don't make any assumptions on the sg_io_hdr_t::dxfer_direction or the sg_io_hdr_t::dxferp in order to determine if it is a valid request. The only way we can check for bad requests is by checking if the length exceeds 256M. Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Fixes: 28676d869bbb (scsi: sg: check for valid direction before starting the request) Reported-by: Jason L Tibbitts III <tibbs@math.uh.edu> Tested-by: Jason L Tibbitts III <tibbs@math.uh.edu> Suggested-by: Doug Gilbert <dgilbert@interlog.com> Cc: Doug Gilbert <dgilbert@interlog.com> Cc: <stable@vger.kernel.org> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-22scsi: sg: fix static checker warning in sg_is_valid_dxferJohannes Thumshirn
commit 14074aba4bcda3764c9a702b276308b89901d5b6 upstream. dxfer_len is an unsigned int and we always assign a value > 0 to it, so it doesn't make any sense to check if it is < 0. We can't really check dxferp as well as we have both NULL and not NULL cases in the possible call paths. So just return true for SG_DXFER_FROM_DEV transfer in sg_is_valid_dxfer(). Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Reported-by: Colin Ian King <colin.king@canonical.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-22scsi: sg: fix SG_DXFER_FROM_DEV transfersJohannes Thumshirn
commit 68c59fcea1f2c6a54c62aa896cc623c1b5bc9b47 upstream. SG_DXFER_FROM_DEV transfers do not necessarily have a dxferp as we set it to NULL for the old sg_io read/write interface, but must have a length bigger than 0. This fixes a regression introduced by commit 28676d869bbb ("scsi: sg: check for valid direction before starting the request") Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Fixes: 28676d869bbb ("scsi: sg: check for valid direction before starting the request") Reported-by: Chris Clayton <chris2553@googlemail.com> Tested-by: Chris Clayton <chris2553@googlemail.com> Cc: Douglas Gilbert <dgilbert@interlog.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Chris Clayton <chris2553@googlemail.com> Acked-by: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Cc: Cristian Crinteanu <crinteanu.cristian@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-22scsi: sg: close race condition in sg_remove_sfp_usercontext()Hannes Reinecke
[ Upstream commit 97d27b0dd015e980ade63fda111fd1353276e28b ] sg_remove_sfp_usercontext() is clearing any sg requests, but needs to take 'rq_list_lock' when modifying the list. Reported-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Tested-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-22scsi: sg: check for valid direction before starting the requestJohannes Thumshirn
[ Upstream commit 28676d869bbb5257b5f14c0c95ad3af3a7019dd5 ] Check for a valid direction before starting the request, otherwise we risk running into an assertion in the scsi midlayer checking for valid requests. [mkp: fixed typo] Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Link: http://www.spinics.net/lists/linux-scsi/msg104400.html Reported-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Hannes Reinecke <hare@suse.com> Tested-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-23scsi: sg: disable SET_FORCE_LOW_DMAHannes Reinecke
commit 745dfa0d8ec26b24f3304459ff6e9eacc5c8351b upstream. The ioctl SET_FORCE_LOW_DMA has never worked since the initial git check-in, and the respective setting is nowadays handled correctly. So disable it entirely. Signed-off-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Tested-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02scsi: sg: Re-fix off by one in sg_fill_request_table()Ben Hutchings
commit 587c3c9f286cee5c9cac38d28c8ae1875f4ec85b upstream. Commit 109bade9c625 ("scsi: sg: use standard lists for sg_requests") introduced an off-by-one error in sg_ioctl(), which was fixed by commit bd46fc406b30 ("scsi: sg: off by one in sg_ioctl()"). Unfortunately commit 4759df905a47 ("scsi: sg: factor out sg_fill_request_table()") moved that code, and reintroduced the bug (perhaps due to a botched rebase). Fix it again. Fixes: 4759df905a47 ("scsi: sg: factor out sg_fill_request_table()") Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk> Acked-by: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-27scsi: sg: fixup infoleak when using SG_GET_REQUEST_TABLEHannes Reinecke
commit 3e0097499839e0fe3af380410eababe5a47c4cf9 upstream. When calling SG_GET_REQUEST_TABLE ioctl only a half-filled table is returned; the remaining part will then contain stale kernel memory information. This patch zeroes out the entire table to avoid this issue. Signed-off-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-27scsi: sg: factor out sg_fill_request_table()Hannes Reinecke
commit 4759df905a474d245752c9dc94288e779b8734dd upstream. Factor out sg_fill_request_table() for better readability. [mkp: typos, applied by hand] Signed-off-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-27scsi: sg: off by one in sg_ioctl()Dan Carpenter
commit bd46fc406b30d1db1aff8dabaff8d18bb423fdcf upstream. If "val" is SG_MAX_QUEUE then we are one element beyond the end of the "rinfo" array so the > should be >=. Fixes: 109bade9c625 ("scsi: sg: use standard lists for sg_requests") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-27scsi: sg: use standard lists for sg_requestsHannes Reinecke
commit 109bade9c625c89bb5ea753aaa1a0a97e6fbb548 upstream. 'Sg_request' is using a private list implementation; convert it to standard lists. Signed-off-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Tested-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-27scsi: sg: remove 'save_scat_len'Hannes Reinecke
commit 136e57bf43dc4babbfb8783abbf707d483cacbe3 upstream. Unused. Signed-off-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Tested-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-13scsi: sg: recheck MMAP_IO request length with lock heldTodd Poynor
commit 8d26f491116feaa0b16de370b6a7ba40a40fa0b4 upstream. Commit 1bc0eb044615 ("scsi: sg: protect accesses to 'reserved' page array") adds needed concurrency protection for the "reserve" buffer. Some checks that are initially made outside the lock are replicated once the lock is taken to ensure the checks and resulting decisions are made using consistent state. The check that a request with flag SG_FLAG_MMAP_IO set fits in the reserve buffer also needs to be performed again under the lock to ensure the reserve buffer length compared against matches the value in effect when the request is linked to the reserve buffer. An -ENOMEM should be returned in this case, instead of switching over to an indirect buffer as for non-MMAP_IO requests. Signed-off-by: Todd Poynor <toddpoynor@google.com> Acked-by: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-13scsi: sg: protect against races between mmap() and SG_SET_RESERVED_SIZETodd Poynor
commit 6a8dadcca81fceff9976e8828cceb072873b7bd5 upstream. Take f_mutex around mmap() processing to protect against races with the SG_SET_RESERVED_SIZE ioctl. Ensure the reserve buffer length remains consistent during the mapping operation, and set the "mmap called" flag to prevent further changes to the reserved buffer size as an atomic operation with the mapping. [mkp: fixed whitespace] Signed-off-by: Todd Poynor <toddpoynor@google.com> Acked-by: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-02scsi: sg: reset 'res_in_use' after unlinking reserved arrayHannes Reinecke
commit e791ce27c3f6a1d3c746fd6a8f8e36c9540ec6f9 upstream. Once the reserved page array is unused we can reset the 'res_in_use' state; here we can do a lazy update without holding the mutex as we only need to check against concurrent access, not concurrent release. [mkp: checkpatch] Fixes: 1bc0eb044615 ("scsi: sg: protect accesses to 'reserved' page array") Signed-off-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Cc: Todd Poynor <toddpoynor@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-02scsi: sg: protect accesses to 'reserved' page arrayHannes Reinecke
commit 1bc0eb0446158cc76562176b80623aa119afee5b upstream. The 'reserved' page array is used as a short-cut for mapping data, saving us to allocate pages per request. However, the 'reserved' array is only capable of holding one request, so this patch introduces a mutex for protect 'sg_fd' against concurrent accesses. Signed-off-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Tested-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> [toddpoynor@google.com: backport to 3.18-4.9, fixup for bad ioctl SG_SET_FORCE_LOW_DMA code removed in later versions and not modified by the original patch.] Signed-off-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Tested-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Todd Poynor <toddpoynor@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-08scsi: sg: check length passed to SG_NEXT_CMD_LENpeter chang
commit bf33f87dd04c371ea33feb821b60d63d754e3124 upstream. The user can control the size of the next command passed along, but the value passed to the ioctl isn't checked against the usable max command size. Signed-off-by: Peter Chang <dpf@google.com> Acked-by: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-23Fix missing sanity check in /dev/sgAl Viro
commit 137d01df511b3afe1f05499aea05f3bafc0fb221 upstream. What happens is that a write to /dev/sg is given a request with non-zero ->iovec_count combined with zero ->dxfer_len. Or with ->dxferp pointing to an array full of empty iovecs. Having write permission to /dev/sg shouldn't be equivalent to the ability to trigger BUG_ON() while holding spinlocks... Found by Dmitry Vyukov and syzkaller. [ The BUG_ON() got changed to a WARN_ON_ONCE(), but this fixes the underlying issue. - Linus ] Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Reported-by: Dmitry Vyukov <dvyukov@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-01-09sg_write()/bsg_write() is not fit to be called under KERNEL_DSAl Viro
commit 128394eff343fc6d2f32172f03e24829539c5835 upstream. Both damn things interpret userland pointers embedded into the payload; worse, they are actually traversing those. Leaving aside the bad API design, this is very much _not_ safe to call with KERNEL_DS. Bail out early if that happens. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-04-12sg: fix dxferp in from_to caseDouglas Gilbert
commit 5ecee0a3ee8d74b6950cb41e8989b0c2174568d4 upstream. One of the strange things that the original sg driver did was let the user provide both a data-out buffer (it followed the sg_header+cdb) _and_ specify a reply length greater than zero. What happened was that the user data-out buffer was copied into some kernel buffers and then the mid level was told a read type operation would take place with the data from the device overwriting the same kernel buffers. The user would then read those kernel buffers back into the user space. From what I can tell, the above action was broken by commit fad7f01e61bf ("sg: set dxferp to NULL for READ with the older SG interface") in 2008 and syzkaller found that out recently. Make sure that a user space pointer is passed through when data follows the sg_header structure and command. Fix the abnormal case when a non-zero reply_len is also given. Fixes: fad7f01e61bf737fe8a3740d803f000db57ecac6 Signed-off-by: Douglas Gilbert <dgilbert@interlog.com> Reviewed-by: Ewan Milne <emilne@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-25drivers/scsi/sg.c: mark VMA as VM_IO to prevent migrationKirill A. Shutemov
commit 461c7fa126794157484dca48e88effa4963e3af3 upstream. Reduced testcase: #include <fcntl.h> #include <unistd.h> #include <sys/mman.h> #include <numaif.h> #define SIZE 0x2000 int main() { int fd; void *p; fd = open("/dev/sg0", O_RDWR); p = mmap(NULL, SIZE, PROT_EXEC, MAP_PRIVATE | MAP_LOCKED, fd, 0); mbind(p, SIZE, 0, NULL, 0, MPOL_MF_MOVE); return 0; } We shouldn't try to migrate pages in sg VMA as we don't have a way to update Sg_scatter_hold::pages accordingly from mm core. Let's mark the VMA as VM_IO to indicate to mm core that the VMA is not migratable. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Doug Gilbert <dgilbert@interlog.com> Cc: David Rientjes <rientjes@google.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Shiraz Hashim <shashim@codeaurora.org> Cc: Hugh Dickins <hughd@google.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: syzkaller <syzkaller@googlegroups.com> Cc: Kostya Serebryany <kcc@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-11-02sg: Fix double-free when drives detach during SG_IOCalvin Owens
In sg_common_write(), we free the block request and return -ENODEV if the device is detached in the middle of the SG_IO ioctl(). Unfortunately, sg_finish_rem_req() also tries to free srp->rq, so we end up freeing rq->cmd in the already free rq object, and then free the object itself out from under the current user. This ends up corrupting random memory via the list_head on the rq object. The most common crash trace I saw is this: ------------[ cut here ]------------ kernel BUG at block/blk-core.c:1420! Call Trace: [<ffffffff81281eab>] blk_put_request+0x5b/0x80 [<ffffffffa0069e5b>] sg_finish_rem_req+0x6b/0x120 [sg] [<ffffffffa006bcb9>] sg_common_write.isra.14+0x459/0x5a0 [sg] [<ffffffff8125b328>] ? selinux_file_alloc_security+0x48/0x70 [<ffffffffa006bf95>] sg_new_write.isra.17+0x195/0x2d0 [sg] [<ffffffffa006cef4>] sg_ioctl+0x644/0xdb0 [sg] [<ffffffff81170f80>] do_vfs_ioctl+0x90/0x520 [<ffffffff81258967>] ? file_has_perm+0x97/0xb0 [<ffffffff811714a1>] SyS_ioctl+0x91/0xb0 [<ffffffff81602afb>] tracesys+0xdd/0xe2 RIP [<ffffffff81281e04>] __blk_put_request+0x154/0x1a0 The solution is straightforward: just set srp->rq to NULL in the failure branch so that sg_finish_rem_req() doesn't attempt to re-free it. Additionally, since sg_rq_end_io() will never be called on the object when this happens, we need to free memory backing ->cmd if it isn't embedded in the object itself. KASAN was extremely helpful in finding the root cause of this bug. Signed-off-by: Calvin Owens <calvinowens@fb.com> Acked-by: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2015-04-11sg_start_req(): use import_iovec()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11sg_start_req(): make sure that there's not too many elements in iovecAl Viro
unfortunately, allowing an arbitrary 16bit value means a possibility of overflow in the calculation of total number of pages in bio_map_user_iov() - we rely on there being no more than PAGE_SIZE members of sum in the first loop there. If that sum wraps around, we end up allocating too small array of pointers to pages and it's easy to overflow it in the second loop. X-Coverup: TINC (and there's no lumber cartel either) Cc: stable@vger.kernel.org # way, way back Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11Merge branch 'iocb' into for-nextAl Viro
2015-03-25fs: move struct kiocb to fs.hChristoph Hellwig
struct kiocb now is a generic I/O container, so move it to fs.h. Also do a #include diet for aio.h while we're at it. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-21Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds
Pull misc SCSI patches from James Bottomley: "This is a short patch set representing a couple of left overs from the merge window (debug removal and MAINTAINER changes). Plus one merge window regression (the local workqueue for hpsa) and a set of bug fixes for several issues (two for scsi-mq and the rest an assortment of long standing stuff, all cc'd to stable)" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: sg: fix EWOULDBLOCK errors with scsi-mq sg: fix unkillable I/O wait deadlock with scsi-mq sg: fix read() error reporting wd719x: add missing .module to wd719x_template hpsa: correct compiler warnings introduced by hpsa-add-local-workqueue patch fixed invalid assignment of 64bit mask to host dma_boundary for scatter gather segment boundary limit. fcoe: Transition maintainership to Vasu am53c974: remove left-over debugging code
2015-02-17sg: fix EWOULDBLOCK errors with scsi-mqTony Battersby
With scsi-mq enabled, userspace programs can get unexpected EWOULDBLOCK (a.k.a. EAGAIN) errors when submitting commands to the SCSI generic driver. Fix by calling blk_get_request() with GFP_KERNEL instead of GFP_ATOMIC. Note: to avoid introducing a potential deadlock, this patch should be applied after the patch titled "sg: fix unkillable I/O wait deadlock with scsi-mq". Cc: <stable@vger.kernel.org> # 3.17+ Signed-off-by: Tony Battersby <tonyb@cybernetics.com> Acked-by: Douglas Gilbert <dgilbert@interlog.com> Tested-by: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2015-02-17sg: fix unkillable I/O wait deadlock with scsi-mqTony Battersby
When using the write()/read() interface for submitting commands, the SCSI generic driver does not call blk_put_request() on a completed SCSI command until userspace calls read() to get the command completion. Since scsi-mq uses a fixed number of preallocated requests, this makes it possible for userspace to exhaust the entire preallocated supply of requests. For places in the kernel that call blk_get_request() with GFP_KERNEL, this can cause the calling process to deadlock in a permanent unkillable I/O wait in blk_get_request() -> ... -> bt_get(). For places in the kernel that call blk_get_request() with GFP_ATOMIC, this can cause blk_get_request() always to return -EWOULDBLOCK. Note that these problems happen only if scsi-mq is enabled. Prevent the problems by calling blk_put_request() as soon as the SCSI command completes instead of waiting for userspace to call read(). Cc: <stable@vger.kernel.org> # 3.17+ Signed-off-by: Tony Battersby <tonyb@cybernetics.com> Acked-by: Douglas Gilbert <dgilbert@interlog.com> Tested-by: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2015-02-15sg: fix read() error reportingTony Battersby
Fix SCSI generic read() incorrectly returning success after detecting an error. Cc: <stable@vger.kernel.org> Signed-off-by: Tony Battersby <tonyb@cybernetics.com> Acked-by: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2015-02-12Merge branch 'for-3.20/core' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull core block IO changes from Jens Axboe: "This contains: - A series from Christoph that cleans up and refactors various parts of the REQ_BLOCK_PC handling. Contributions in that series from Dongsu Park and Kent Overstreet as well. - CFQ: - A bug fix for cfq for realtime IO scheduling from Jeff Moyer. - A stable patch fixing a potential crash in CFQ in OOM situations. From Konstantin Khlebnikov. - blk-mq: - Add support for tag allocation policies, from Shaohua. This is a prep patch enabling libata (and other SCSI parts) to use the blk-mq tagging, instead of rolling their own. - Various little tweaks from Keith and Mike, in preparation for DM blk-mq support. - Minor little fixes or tweaks from me. - A double free error fix from Tony Battersby. - The partition 4k issue fixes from Matthew and Boaz. - Add support for zero+unprovision for blkdev_issue_zeroout() from Martin" * 'for-3.20/core' of git://git.kernel.dk/linux-block: (27 commits) block: remove unused function blk_bio_map_sg block: handle the null_mapped flag correctly in blk_rq_map_user_iov blk-mq: fix double-free in error path block: prevent request-to-request merging with gaps if not allowed blk-mq: make blk_mq_run_queues() static dm: fix multipath regression due to initializing wrong request cfq-iosched: handle failure of cfq group allocation block: Quiesce zeroout wrapper block: rewrite and split __bio_copy_iov() block: merge __bio_map_user_iov into bio_map_user_iov block: merge __bio_map_kern into bio_map_kern block: pass iov_iter to the BLOCK_PC mapping functions block: add a helper to free bio bounce buffer pages block: use blk_rq_map_user_iov to implement blk_rq_map_user block: simplify bio_map_kern block: mark blk-mq devices as stackable block: keep established cmd_flags when cloning into a blk-mq request block: add blk-mq support to blk_insert_cloned_request() block: require blk_rq_prep_clone() be given an initialized clone request blk-mq: add tag allocation policy ...
2015-02-05block: pass iov_iter to the BLOCK_PC mapping functionsKent Overstreet
Make use of a new interface provided by iov_iter, backed by scatter-gather list of iovec, instead of the old interface based on sg_iovec. Also use iov_iter_advance() instead of manual iteration. This commit should contain only literal replacements, without functional changes. Cc: Christoph Hellwig <hch@infradead.org> Cc: Jens Axboe <axboe@kernel.dk> Cc: Doug Gilbert <dgilbert@interlog.com> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Signed-off-by: Kent Overstreet <kmo@daterainc.com> [dpark: add more description in commit message] Signed-off-by: Dongsu Park <dongsu.park@profitbricks.com> [hch: fixed to do a deep clone of the iov_iter, and to properly use the iov_iter direction] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Ming Lei <tom.leiming@gmail.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2015-02-02sg: remove an unused variableBart Van Assche
The 'data_dir' variable is not used in sg_common_write(), hence remove this variable. Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com> Acked-by: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-12scsi: split scsi_nonblockable_ioctlChristoph Hellwig
The calling conventions for this function are bad as it could return -ENODEV both for a device not currently online and a not recognized ioctl. Add a new scsi_ioctl_block_when_processing_errors function that wraps scsi_block_when_processing_errors with the a special case for the SG_SCSI_RESET ioctl command, and handle the SG_SCSI_RESET case itself in scsi_ioctl. All callers of scsi_ioctl now must call the above helper to check for the EH state, so that the ioctl handler itself doesn't have to. Reported-by: Robert Elliott <Elliott@hp.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-12scsi: refactor scsi_reset_provider handlingChristoph Hellwig
Pull the common code from the two callers into the function, and rename it to scsi_ioctl_reset. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-11-12scsi: use sdev as argument for sense code printingHannes Reinecke
We should be using the standard dev_printk() variants for sense code printing. [hch: remove __scsi_print_sense call in xen-scsiback, Acked by Juergen] [hch: folded bracing fix from Dan Carpenter] Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Robert Elliott <elliott@hp.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-12scsi: introduce sdev_prefix_printk()Hannes Reinecke
Like scmd_printk(), but the device name is passed in as a string. Can be used by eg ULDs which do not have access to the scsi_cmnd structure. Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Robert Elliott <elliott@hp.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-12scsi: add SG_SCSI_RESET_NO_ESCALATE flag to SG_SCSI_RESET ioctlDouglas Gilbert
Further to a January 2013 thread titled: "[PATCH] SG_SCSI_RESET ioctl should only perform requested operation" by Jeremy Linton a patch (v3) is presented that expands the existing ioctl to include "no_escalate" versions to the existing resets. This requires no changes to SCSI low level drivers (LLDs); it adds several more finely tuned reset options to the user space. For example: /* This call remains the same, with the same escalating semantics * if the device (LU) reset fail. That is: on failure to try a * target reset and if that fails, try a bus reset, and if that fails * try a host (i.e. LLD) reset. */ val = SG_SCSI_RESET_DEVICE; res = ioctl(<sg_or_block_fd>, SG_SCSI_RESET, &val); /* What follows is a new option introduced by this patch series. Only * a device reset is attempted. If that fails then an appropriate * error code is provided. N.B. There is no reset escalation. */ val = SG_SCSI_RESET_DEVICE | SG_SCSI_RESET_NO_ESCALATE; res = ioctl(<sg_or_block_fd>, SG_SCSI_RESET, &val); Signed-off-by: Douglas Gilbert <dgilbert@interlog.com> Reviewed-by: Jeremy Linton <jlinton@tributary.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-08-28block,scsi: fixup blk_get_request dead queue scenariosJoe Lawrence
The blk_get_request function may fail in low-memory conditions or during device removal (even if __GFP_WAIT is set). To distinguish between these errors, modify the blk_get_request call stack to return the appropriate ERR_PTR. Verify that all callers check the return status and consider IS_ERR instead of a simple NULL pointer check. For consistency, make a similar change to the blk_mq_alloc_request leg of blk_get_request. It may fail if the queue is dead, or the caller was unwilling to wait. Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com> Acked-by: Jiri Kosina <jkosina@suse.cz> [for pktdvd] Acked-by: Boaz Harrosh <bharrosh@panasas.com> [for osd] Reviewed-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2014-07-25scsi: convert device_busy to atomic_tChristoph Hellwig
Avoid taking the queue_lock to check the per-device queue limit. Instead we do an atomic_inc_return early on to grab our slot in the queue, and if necessary decrement it after finishing all checks. Unlike the host and target busy counters this doesn't allow us to avoid the queue_lock in the request_fn due to the way the interface works, but it'll allow us to prepare for using the blk-mq code, which doesn't use the queue_lock at all, and it at least avoids a queue_lock round trip in scsi_device_unbusy, which is still important given how busy the queue_lock is. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Webb Scales <webbnh@hp.com> Acked-by: Jens Axboe <axboe@kernel.dk> Tested-by: Bart Van Assche <bvanassche@acm.org> Tested-by: Robert Elliott <elliott@hp.com>
2014-07-17scsi: Implement sg_printk()Hannes Reinecke
Update the sg driver to use dev_printk() variants instead of plain printk(); this will prefix logging messages with the appropriate device. Signed-off-by: Hannes Reinecke <hare@suse.de> Acked-by: Doug Gilbert <dgilbert@interlog.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-17scsi: use 64-bit LUNsHannes Reinecke
The SCSI standard defines 64-bit values for LUNs, and large arrays employing large or hierarchical LUN numbers become more and more common. So update the linux SCSI stack to use 64-bit LUN numbers. Signed-off-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Christoph Hellwig <hch@infradead.org> Reviewed-by: Ewan Milne <emilne@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-17sg: O_EXCL and other lock handlingDouglas Gilbert
This addresses a problem reported by Vaughan Cao concerning the correctness of the O_EXCL logic in the sg driver. POSIX doesn't defined O_EXCL semantics on devices but "allow only one open file descriptor at a time per sg device" is a rough definition. The sg driver's semantics have been to wait on an open() when O_NONBLOCK is not given and there are O_EXCL headwinds. Nasty things can happen during that wait such as the device being detached (removed). So multiple locks are reworked in this patch making it large and hard to break down into digestible bits. This patch is against Linus's current git repository which doesn't include any sg patches sent in the last few weeks. Hence this patch touches as little as possible that it doesn't need to and strips out most SCSI_LOG_TIMEOUT() changes in v3 because Hannes said he was going to rework all that stuff. The sg3_utils package has several test programs written to test this patch. See examples/sg_tst_excl*.cpp . Not all the locks and flags in sg have been re-worked in this patch, notably sg_request::done . That can wait for a follow-up patch if this one meets with approval. Signed-off-by: Douglas Gilbert <dgilbert@interlog.com> Reviewed-by: Hannes Reinecke <hare@suse.de>
2014-07-17sg: add SG_FLAG_Q_AT_TAIL flagDouglas Gilbert
When the SG_IO ioctl was copied into the block layer and later into the bsg driver, subtle differences emerged. One difference is the way injected commands are queued through the block layer (i.e. this is not SCSI device queueing nor SATA NCQ). Summarizing: - SG_IO in the block layer: blk_exec*(at_head=false) - sg SG_IO: at_head=true - bsg SG_IO: at_head=true Some time ago Boaz Harrosh introduced a sg v4 flag called BSG_FLAG_Q_AT_TAIL to override the bsg driver default. This patch does the equivalent for the sg driver. ChangeLog: Introduce SG_FLAG_Q_AT_TAIL flag to cause commands to be injected into the block layer with at_head=false. Signed-off-by: Douglas Gilbert <dgilbert@interlog.com> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Reviewed-by: Ewan D. Milne <emilne@redhat.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-17sg: relax 16 byte cdb restrictionDouglas Gilbert
- remove the 16 byte CDB (SCSI command) length limit from the sg driver by handling longer CDBs the same way as the bsg driver. Remove comment from sg.h public interface about the cmd_len field being limited to 16 bytes. - remove some dead code caused by this change - cleanup comment block at the top of sg.h, fix urls Signed-off-by: Douglas Gilbert <dgilbert@interlog.com> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-07-17sg: prevent integer overflow when converting from sectors to bytesAkinobu Mita
This prevents integer overflow when converting the request queue's max_sectors from sectors to bytes. However, this is a preparation for extending the data type of max_sectors in struct Scsi_Host and scsi_host_template. So, it is impossible to happen this integer overflow for now, because SCSI low-level drivers can not specify max_sectors greater than 0xffff due to the data type limitation. Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Acked by: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: Christoph Hellwig <hch@lst.de>