kernel/git/stable/linux.git/drivers/scsi/sg.c, branch linux-3.2.y

Fix missing sanity check in /dev/sg

2017-03-16T02:18:51+00:00

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 Reported-by: Dmitry Vyukov Reviewed-by: Christoph Hellwig Signed-off-by: Linus Torvalds [bwh: Backported to 3.2: we're not using iov_iter, but can check the byte length after truncation] Signed-off-by: Ben Hutchings

sg_write()/bsg_write() is not fit to be called under KERNEL_DS

2017-02-23T03:51:06+00:00

commit a0ac402cfcdc904f9772e1762b3fda112dcc56a0 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. Cc: stable@vger.kernel.org Signed-off-by: Al Viro Signed-off-by: Ben Hutchings

sg: Fix double-free when drives detach during SG_IO

2017-02-23T03:51:03+00:00

commit f3951a3709ff50990bf3e188c27d346792103432 upstream. 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: [] blk_put_request+0x5b/0x80 [] sg_finish_rem_req+0x6b/0x120 [sg] [] sg_common_write.isra.14+0x459/0x5a0 [sg] [] ? selinux_file_alloc_security+0x48/0x70 [] sg_new_write.isra.17+0x195/0x2d0 [sg] [] sg_ioctl+0x644/0xdb0 [sg] [] do_vfs_ioctl+0x90/0x520 [] ? file_has_perm+0x97/0xb0 [] SyS_ioctl+0x91/0xb0 [] tracesys+0xdd/0xe2 RIP [] __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 Acked-by: Douglas Gilbert Signed-off-by: Martin K. Petersen [bwh: Backported to 3.2: - sg_finish_rem_req() would not free srp->rq->cmd so don't do it here either - Adjust context] Signed-off-by: Ben Hutchings

sg: fix dxferp in from_to case

2016-04-30T22:05:17+00:00

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 Reviewed-by: Ewan Milne Signed-off-by: Martin K. Petersen Signed-off-by: Ben Hutchings

sg_start_req(): make sure that there's not too many elements in iovec

2015-08-06T23:32:04+00:00

commit 451a2886b6bf90e2fb378f7c46c655450fb96e81 upstream. 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) Signed-off-by: Al Viro [bwh: s/MAX_UIOVEC/UIO_MAXIOV/. This was fixed upstream by commit fdc81f45e9f5 ("sg_start_req(): use import_iovec()"), but we don't have that function.] Signed-off-by: Ben Hutchings

sg: fix read() error reporting

2015-05-09T22:16:18+00:00

commit 3b524a683af8991b4eab4182b947c65f0ce1421b upstream. Fix SCSI generic read() incorrectly returning success after detecting an error. Signed-off-by: Tony Battersby Acked-by: Douglas Gilbert Signed-off-by: James Bottomley Signed-off-by: Ben Hutchings

scsi/sg: use printk_ratelimited instead of printk_ratelimit

2011-09-15T12:05:25+00:00

Since printk_ratelimit() shouldn't be used anymore (see comment in include/linux/printk.h), replace it with printk_ratelimited. Signed-off-by: Christian Dietrich Signed-off-by: Jiri Kosina

Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial

2010-10-24T20:41:39+00:00

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (39 commits) Update broken web addresses in arch directory. Update broken web addresses in the kernel. Revert "drivers/usb: Remove unnecessary return's from void functions" for musb gadget Revert "Fix typo: configuation => configuration" partially ida: document IDA_BITMAP_LONGS calculation ext2: fix a typo on comment in ext2/inode.c drivers/scsi: Remove unnecessary casts of private_data drivers/s390: Remove unnecessary casts of private_data net/sunrpc/rpc_pipe.c: Remove unnecessary casts of private_data drivers/infiniband: Remove unnecessary casts of private_data drivers/gpu/drm: Remove unnecessary casts of private_data kernel/pm_qos_params.c: Remove unnecessary casts of private_data fs/ecryptfs: Remove unnecessary casts of private_data fs/seq_file.c: Remove unnecessary casts of private_data arm: uengine.c: remove C99 comments arm: scoop.c: remove C99 comments Fix typo configue => configure in comments Fix typo: configuation => configuration Fix typo interrest[ing|ed] => interest[ing|ed] Fix various typos of valid in comments ... Fix up trivial conflicts in: drivers/char/ipmi/ipmi_si_intf.c drivers/usb/gadget/rndis.c net/irda/irnet/irnet_ppp.c

Merge branch 'for-2.6.37/core' of git://git.kernel.dk/linux-2.6-block

2010-10-23T00:00:32+00:00

* 'for-2.6.37/core' of git://git.kernel.dk/linux-2.6-block: (39 commits) cfq-iosched: Fix a gcc 4.5 warning and put some comments block: Turn bvec_k{un,}map_irq() into static inline functions block: fix accounting bug on cross partition merges block: Make the integrity mapped property a bio flag block: Fix double free in blk_integrity_unregister block: Ensure physical block size is unsigned int blkio-throttle: Fix possible multiplication overflow in iops calculations blkio-throttle: limit max iops value to UINT_MAX blkio-throttle: There is no need to convert jiffies to milli seconds blkio-throttle: Fix link failure failure on i386 blkio: Recalculate the throttled bio dispatch time upon throttle limit change blkio: Add root group to td->tg_list blkio: deletion of a cgroup was causes oops blkio: Do not export throttle files if CONFIG_BLK_DEV_THROTTLING=n block: set the bounce_pfn to the actual DMA limit rather than to max memory block: revert bad fix for memory hotplug causing bounces Fix compile error in blk-exec.c for !CONFIG_DETECT_HUNG_TASK block: set the bounce_pfn to the actual DMA limit rather than to max memory block: Prevent hang_check firing during long I/O cfq: improve fsync performance for small files ... Fix up trivial conflicts due to __rcu sparse annotation in include/linux/genhd.h

Merge branch 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl

2010-10-22T17:52:56+00:00

* 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl: vfs: make no_llseek the default vfs: don't use BKL in default_llseek llseek: automatically add .llseek fop libfs: use generic_file_llseek for simple_attr mac80211: disallow seeks in minstrel debug code lirc: make chardev nonseekable viotape: use noop_llseek raw: use explicit llseek file operations ibmasmfs: use generic_file_llseek spufs: use llseek in all file operations arm/omap: use generic_file_llseek in iommu_debug lkdtm: use generic_file_llseek in debugfs net/wireless: use generic_file_llseek in debugfs drm: use noop_llseek