Bradley Bolen 022af4898b ubi: block: Fix locking for idr_alloc/idr_remove ... commit 7f29ae9f97 upstream. This fixes a race with idr_alloc where gd->first_minor can be set to the same value for two simultaneous calls to ubiblock_create. Each instance calls device_add_disk with the same first_minor. device_add_disk calls bdi_register_owner which generates several warnings. WARNING: CPU: 1 PID: 179 at kernel-source/fs/sysfs/dir.c:31 sysfs_warn_dup+0x68/0x88 sysfs: cannot create duplicate filename '/devices/virtual/bdi/252:2' WARNING: CPU: 1 PID: 179 at kernel-source/lib/kobject.c:240 kobject_add_internal+0x1ec/0x2f8 kobject_add_internal failed for 252:2 with -EEXIST, don't try to register things with the same name in the same directory WARNING: CPU: 1 PID: 179 at kernel-source/fs/sysfs/dir.c:31 sysfs_warn_dup+0x68/0x88 sysfs: cannot create duplicate filename '/dev/block/252:2' However, device_add_disk does not error out when bdi_register_owner returns an error. Control continues until reaching blk_register_queue. It then BUGs. kernel BUG at kernel-source/fs/sysfs/group.c:113! [<c01e26cc>] (internal_create_group) from [<c01e2950>] (sysfs_create_group+0x20/0x24) [<c01e2950>] (sysfs_create_group) from [<c00e3d38>] (blk_trace_init_sysfs+0x18/0x20) [<c00e3d38>] (blk_trace_init_sysfs) from [<c02bdfbc>] (blk_register_queue+0xd8/0x154) [<c02bdfbc>] (blk_register_queue) from [<c02cec84>] (device_add_disk+0x194/0x44c) [<c02cec84>] (device_add_disk) from [<c0436ec8>] (ubiblock_create+0x284/0x2e0) [<c0436ec8>] (ubiblock_create) from [<c0427bb8>] (vol_cdev_ioctl+0x450/0x554) [<c0427bb8>] (vol_cdev_ioctl) from [<c0189110>] (vfs_ioctl+0x30/0x44) [<c0189110>] (vfs_ioctl) from [<c01892e0>] (do_vfs_ioctl+0xa0/0x790) [<c01892e0>] (do_vfs_ioctl) from [<c0189a14>] (SyS_ioctl+0x44/0x68) [<c0189a14>] (SyS_ioctl) from [<c0010640>] (ret_fast_syscall+0x0/0x34) Locking idr_alloc/idr_remove removes the race and keeps gd->first_minor unique. Fixes: 2bf50d42f3 ("UBI: block: Dynamically allocate minor numbers") Signed-off-by: Bradley Bolen <bradleybolen@gmail.com> Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2018-02-16 20:09:41 +01:00
..
chips	mtd: avoid stack overflow in MTD CFI code	2017-05-08 07:46:01 +02:00
devices	MTD updates for 4.4-rc1:	2015-11-06 11:50:24 -08:00
lpddr	mtd: lpddr: show parent device in sysfs	2015-10-13 09:21:17 -07:00
maps	mtd: pmcmsp: use kstrndup instead of kmalloc+strncpy	2017-03-18 19:09:56 +08:00
nand	mtd: nand: sunxi: Fix ECC strength choice	2018-02-16 20:09:41 +01:00
onenand	mtd: onenand: fix deadlock in onenand_block_markbad	2016-04-12 09:09:05 -07:00
spi-nor	mtd: spi-nor: fix spansion quad enable	2017-06-29 12:48:52 +02:00
tests	mtd: tests: Replace timeval with ktime_t	2015-10-26 13:23:47 -07:00
ubi	ubi: block: Fix locking for idr_alloc/idr_remove	2018-02-16 20:09:41 +01:00
afs.c
ar7part.c
bcm47xxpart.c	mtd: bcm47xxpart: don't fail because of bit-flips	2017-07-05 14:37:18 +02:00
bcm63xxpart.c
cmdlinepart.c	mtd: cmdlinepart: convert printk() to pr_*()	2015-09-28 18:37:32 -07:00
ftl.c
inftlcore.c
inftlmount.c
Kconfig
Makefile
mtd_blkdevs.c	mtd: blkdevs: fix potential deadlock + lockdep warnings	2015-10-30 17:24:43 -07:00
mtdblock_ro.c
mtdblock.c
mtdchar.c	mtd: provide proper 32/64-bit compat_ioctl() support for BLKPG	2015-09-29 13:37:04 -07:00
mtdconcat.c
mtdcore.c	mtd: fix cmdlinepart parser, early naming for auto-filled MTD	2016-01-04 10:54:18 -08:00
mtdcore.h
mtdoops.c
mtdpart.c	mtd: mtdpart: Do not fail mtd probe when parsing partitions fails	2015-10-26 18:43:48 -07:00
mtdsuper.c
mtdswap.c
nftlcore.c
nftlmount.c
ofpart.c	doc: dt: mtd: partitions: add compatible property to "partitions" node	2015-12-08 17:10:20 -08:00
redboot.c
rfd_ftl.c
sm_ftl.c
sm_ftl.h
ssfdc.c