kernel.git/drivers/mtd/ubi/build.c, branch linux-6.3.y

ubi: Fix failure attaching when vid_hdr offset equals to (sub)page size

2023-03-29T21:32:57Z

Following process will make ubi attaching failed since commit 1b42b1a36fc946 ("ubi: ensure that VID header offset ... size"): ID="0xec,0xa1,0x00,0x15" # 128M 128KB 2KB modprobe nandsim id_bytes=$ID flash_eraseall /dev/mtd0 modprobe ubi mtd="0,2048" # set vid_hdr offset as 2048 (one page) (dmesg): ubi0 error: ubi_attach_mtd_dev [ubi]: VID header offset 2048 too large. UBI error: cannot attach mtd0 UBI error: cannot initialize UBI, error -22 Rework original solution, the key point is making sure 'vid_hdr_shift + UBI_VID_HDR_SIZE < ubi->vid_hdr_alsize', so we should check vid_hdr_shift rather not vid_hdr_offset. Then, ubi still support (sub)page aligined VID header offset. Fixes: 1b42b1a36fc946 ("ubi: ensure that VID header offset ... size") Signed-off-by: Zhihao Cheng Tested-by: Nicolas Schichan Tested-by: Miquel Raynal # v5.10, v4.19 Signed-off-by: Richard Weinberger

mtd: ubi: wire-up parent MTD device

2023-02-13T21:23:03Z

Wire up the device parent pointer of UBI devices to their lower MTD device, typically an MTD partition or whole-chip device. The most noticeable change is that in sysfs, previously ubi devices would be could in /sys/devices/virtual/ubi while after this change they would be correctly attached to their parent MTD device, e.g. /sys/devices/platform/1100d000.spi/spi_master/spi1/spi1.0/mtd/mtd2/ubi0. Locating UBI devices using /sys/class/ubi/ of course still works as well. Signed-off-by: Daniel Golle Signed-off-by: Richard Weinberger

ubi: Fix possible null-ptr-deref in ubi_free_volume()

2023-02-02T20:13:44Z

It willl cause null-ptr-deref in the following case: uif_init() ubi_add_volume() cdev_add() -> if it fails, call kill_volumes() device_register() kill_volumes() -> if ubi_add_volume() fails call this function ubi_free_volume() cdev_del() device_unregister() -> trying to delete a not added device, it causes null-ptr-deref So in ubi_free_volume(), it delete devices whether they are added or not, it will causes null-ptr-deref. Handle the error case whlie calling ubi_add_volume() to fix this problem. If add volume fails, set the corresponding vol to null, so it can not be accessed in kill_volumes() and release the resource in ubi_add_volume() error path. Fixes: 801c135ce73d ("UBI: Unsorted Block Images") Suggested-by: Zhihao Cheng Signed-off-by: Yang Yingliang Reviewed-by: Zhihao Cheng Signed-off-by: Richard Weinberger

ubi: fastmap: Add fastmap control support for module parameter

2023-02-02T20:13:43Z

The UBI driver can use the IOCTL to disable the fastmap after the mainline 669d204469c4 ("ubi: fastmap: Add fastmap control support for 'UBI_IOCATT' ioctl"). To destroy the fastmap on a old image, we need to reattach the device in user space. However, if the UBI driver build in kernel and the UBI volume is the root partition, the UBI device cannot be reattached in user space. To disable fastmap in this case, the UBI must provide the kernel cmdline parameters to disable fastmap during attach. This patch add 'enable_fm' as 5th module init parameter of mtd=xx to control fastmap enable or not. When the value is 0, fastmap will not create and existed fastmap will destroyed for the given ubi device. Default value is 0. To enable or disable fastmap during module loading, fm_autoconvert must be set to non-zero. +-----------------+---------------+---------------------------+ | \ | enable_fm=0 | enable_fm=1 | +-----------------+---------------+---------------------------+ |fm_autoconvert=Y | disable fm | enable fm | +---------------------------------+---------------------------+ |fm_autoconvert=N | disable fm | Enable fastmap if fastmap | | | | exists on the old image | +-------------------------------------------------------------+ Example: # - Attach mtd1 to ubi1, disable fastmap, mtd2 to ubi2, enable fastmap. # modprobe ubi mtd=1,0,0,1,0 mtd=2,0,0,2,1 fm_autoconvert=1 # - If 5th parameter is not specified, the value is 0, fastmap is disable # modprobe ubi mtd=1 fm_autoconvert=1 Link: https://bugzilla.kernel.org/show_bug.cgi?id=216623 Signed-off-by: ZhaoLong Wang Signed-off-by: Richard Weinberger

ubi: ensure that VID header offset + VID header size <= alloc, size

2023-02-02T20:13:33Z

Ensure that the VID header offset + VID header size does not exceed the allocated area to avoid slab OOB. BUG: KASAN: slab-out-of-bounds in crc32_body lib/crc32.c:111 [inline] BUG: KASAN: slab-out-of-bounds in crc32_le_generic lib/crc32.c:179 [inline] BUG: KASAN: slab-out-of-bounds in crc32_le_base+0x58c/0x626 lib/crc32.c:197 Read of size 4 at addr ffff88802bb36f00 by task syz-executor136/1555 CPU: 2 PID: 1555 Comm: syz-executor136 Tainted: G W 6.0.0-1868 #1 Hardware name: Red Hat KVM, BIOS 1.13.0-2.module+el8.3.0+7860+a7792d29 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x85/0xad lib/dump_stack.c:106 print_address_description mm/kasan/report.c:317 [inline] print_report.cold.13+0xb6/0x6bb mm/kasan/report.c:433 kasan_report+0xa7/0x11b mm/kasan/report.c:495 crc32_body lib/crc32.c:111 [inline] crc32_le_generic lib/crc32.c:179 [inline] crc32_le_base+0x58c/0x626 lib/crc32.c:197 ubi_io_write_vid_hdr+0x1b7/0x472 drivers/mtd/ubi/io.c:1067 create_vtbl+0x4d5/0x9c4 drivers/mtd/ubi/vtbl.c:317 create_empty_lvol drivers/mtd/ubi/vtbl.c:500 [inline] ubi_read_volume_table+0x67b/0x288a drivers/mtd/ubi/vtbl.c:812 ubi_attach+0xf34/0x1603 drivers/mtd/ubi/attach.c:1601 ubi_attach_mtd_dev+0x6f3/0x185e drivers/mtd/ubi/build.c:965 ctrl_cdev_ioctl+0x2db/0x347 drivers/mtd/ubi/cdev.c:1043 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x193/0x213 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3e/0x86 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0x0 RIP: 0033:0x7f96d5cf753d Code: RSP: 002b:00007fffd72206f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f96d5cf753d RDX: 0000000020000080 RSI: 0000000040186f40 RDI: 0000000000000003 RBP: 0000000000400cd0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000400be0 R13: 00007fffd72207e0 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 1555: kasan_save_stack+0x20/0x3d mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:437 [inline] ____kasan_kmalloc mm/kasan/common.c:516 [inline] __kasan_kmalloc+0x88/0xa3 mm/kasan/common.c:525 kasan_kmalloc include/linux/kasan.h:234 [inline] __kmalloc+0x138/0x257 mm/slub.c:4429 kmalloc include/linux/slab.h:605 [inline] ubi_alloc_vid_buf drivers/mtd/ubi/ubi.h:1093 [inline] create_vtbl+0xcc/0x9c4 drivers/mtd/ubi/vtbl.c:295 create_empty_lvol drivers/mtd/ubi/vtbl.c:500 [inline] ubi_read_volume_table+0x67b/0x288a drivers/mtd/ubi/vtbl.c:812 ubi_attach+0xf34/0x1603 drivers/mtd/ubi/attach.c:1601 ubi_attach_mtd_dev+0x6f3/0x185e drivers/mtd/ubi/build.c:965 ctrl_cdev_ioctl+0x2db/0x347 drivers/mtd/ubi/cdev.c:1043 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl fs/ioctl.c:856 [inline] __x64_sys_ioctl+0x193/0x213 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3e/0x86 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0x0 The buggy address belongs to the object at ffff88802bb36e00 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 0 bytes to the right of 256-byte region [ffff88802bb36e00, ffff88802bb36f00) The buggy address belongs to the physical page: page:00000000ea4d1263 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2bb36 head:00000000ea4d1263 order:1 compound_mapcount:0 compound_pincount:0 flags: 0xfffffc0010200(slab|head|node=0|zone=1|lastcpupid=0x1fffff) raw: 000fffffc0010200 ffffea000066c300 dead000000000003 ffff888100042b40 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88802bb36e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88802bb36e80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88802bb36f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88802bb36f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802bb37000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== Fixes: 801c135ce73d ("UBI: Unsorted Block Images") Reported-by: syzkaller Signed-off-by: George Kennedy Signed-off-by: Richard Weinberger

ubi: fastmap: Add fastmap control support for 'UBI_IOCATT' ioctl

2022-09-21T16:29:18Z

[1] suggests that fastmap is suitable for large flash devices. Module parameter 'fm_autoconvert' is a coarse grained switch to enable all ubi devices to generate fastmap, which may turn on fastmap even for small flash devices. This patch imports a new field 'disable_fm' in struct 'ubi_attach_req' to support following situations by ioctl 'UBI_IOCATT'. [old functions] A. Disable 'fm_autoconvert': Disbable fastmap for all ubi devices B. Enable 'fm_autoconvert': Enable fastmap for all ubi devices [new function] C. Enable 'fm_autoconvert', set 'disable_fm' for given device: Don't create new fastmap and do full scan (existed fastmap will be destroyed) for the given ubi device. A simple test case in [2]. [1] http://www.linux-mtd.infradead.org/doc/ubi.html#L_fastmap [2] https://bugzilla.kernel.org/show_bug.cgi?id=216278 Signed-off-by: Zhihao Cheng Signed-off-by: Richard Weinberger

ubi: Fix race condition between ctrl_cdev_ioctl and ubi_cdev_ioctl

2022-01-09T20:13:28Z

Hulk Robot reported a KASAN report about use-after-free: ================================================================== BUG: KASAN: use-after-free in __list_del_entry_valid+0x13d/0x160 Read of size 8 at addr ffff888035e37d98 by task ubiattach/1385 [...] Call Trace: klist_dec_and_del+0xa7/0x4a0 klist_put+0xc7/0x1a0 device_del+0x4d4/0xed0 cdev_device_del+0x1a/0x80 ubi_attach_mtd_dev+0x2951/0x34b0 [ubi] ctrl_cdev_ioctl+0x286/0x2f0 [ubi] Allocated by task 1414: device_add+0x60a/0x18b0 cdev_device_add+0x103/0x170 ubi_create_volume+0x1118/0x1a10 [ubi] ubi_cdev_ioctl+0xb7f/0x1ba0 [ubi] Freed by task 1385: cdev_device_del+0x1a/0x80 ubi_remove_volume+0x438/0x6c0 [ubi] ubi_cdev_ioctl+0xbf4/0x1ba0 [ubi] [...] ================================================================== The lock held by ctrl_cdev_ioctl is ubi_devices_mutex, but the lock held by ubi_cdev_ioctl is ubi->device_mutex. Therefore, the two locks can be concurrent. ctrl_cdev_ioctl contains two operations: ubi_attach and ubi_detach. ubi_detach is bug-free because it uses reference counting to prevent concurrency. However, uif_init and uif_close in ubi_attach may race with ubi_cdev_ioctl. uif_init will race with ubi_cdev_ioctl as in the following stack. cpu1 cpu2 cpu3 _______________________|________________________|______________________ ctrl_cdev_ioctl ubi_attach_mtd_dev uif_init ubi_cdev_ioctl ubi_create_volume cdev_device_add ubi_add_volume // sysfs exist kill_volumes ubi_cdev_ioctl ubi_remove_volume cdev_device_del // first free ubi_free_volume cdev_del // double free cdev_device_del And uif_close will race with ubi_cdev_ioctl as in the following stack. cpu1 cpu2 cpu3 _______________________|________________________|______________________ ctrl_cdev_ioctl ubi_attach_mtd_dev uif_init ubi_cdev_ioctl ubi_create_volume cdev_device_add ubi_debugfs_init_dev //error goto out_uif; uif_close kill_volumes ubi_cdev_ioctl ubi_remove_volume cdev_device_del // first free ubi_free_volume // double free The cause of this problem is that commit 714fb87e8bc0 make device "available" before it becomes accessible via sysfs. Therefore, we roll back the modification. We will fix the race condition between ubi device creation and udev by removing ubi_get_device in vol_attribute_show and dev_attribute_show.This avoids accessing uninitialized ubi_devices[ubi_num]. ubi_get_device is used to prevent devices from being deleted during sysfs execution. However, now kernfs ensures that devices will not be deleted before all reference counting are released. The key process is shown in the following stack. device_del device_remove_attrs device_remove_groups sysfs_remove_groups sysfs_remove_group remove_files kernfs_remove_by_name kernfs_remove_by_name_ns __kernfs_remove kernfs_drain Fixes: 714fb87e8bc0 ("ubi: Fix race condition between ubi device creation and udev") Reported-by: Hulk Robot Signed-off-by: Baokun Li Signed-off-by: Richard Weinberger

ubi: Fix fall-through warnings for Clang

2021-04-15T20:00:43Z

In preparation to enable -Wimplicit-fallthrough for Clang, fix a warning by explicitly adding a break statement instead of letting the code fall through to the next case. Link: https://github.com/KSPP/linux/issues/115 Signed-off-by: Gustavo A. R. Silva Signed-off-by: Richard Weinberger

Merge tag 'for-linus-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs

2020-12-18T01:46:34Z

Pull jffs2, ubi and ubifs updates from Richard Weinberger: "JFFS2: - Fix for a remount regression - Fix for an abnormal GC exit - Fix for a possible NULL pointer issue while mounting UBI: - Add support ECC-ed NOR flash - Removal of dead code UBIFS: - Make node dumping debug code more reliable - Various cleanups: less ifdefs, less typos - Fix for an info leak" * tag 'for-linus-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs: ubifs: ubifs_dump_node: Dump all branches of the index node ubifs: ubifs_dump_sleb: Remove unused function ubifs: Pass node length in all node dumping callers Revert "ubifs: Fix out-of-bounds memory access caused by abnormal value of node_len" ubifs: Limit dumping length by size of memory which is allocated for the node ubifs: Remove the redundant return in dbg_check_nondata_nodes_order jffs2: Fix NULL pointer dereference in rp_size fs option parsing ubifs: Fixed print foramt mismatch in ubifs ubi: Do not zero out EC and VID on ECC-ed NOR flashes jffs2: remove trailing semicolon in macro definition ubifs: Fix error return code in ubifs_init_authentication() ubifs: wbuf: Don't leak kernel memory to flash ubi: Remove useless code in bytes_str_to_int ubifs: Fix the printing type of c->big_lpt jffs2: Allow setting rp_size to zero during remounting jffs2: Fix ignoring mounting options problem during remounting jffs2: Fix GC exit abnormally ubifs: Code cleanup by removing ifdef macro surrounding jffs2: Fix if/else empty body warnings ubifs: Delete duplicated words + other fixes

ubi: Do not zero out EC and VID on ECC-ed NOR flashes

2020-12-13T20:57:21Z

For NOR flashes EC and VID are zeroed out before an erase is issued to make sure UBI does not mistakenly treat the PEB as used and associate it with an LEB. But on some flashes, like the Cypress Semper S28 SPI NOR flash family, multi-pass page programming is not allowed on the default ECC scheme. This means zeroing out these magic numbers will result in the flash throwing a page programming error. Do not zero out EC and VID for such flashes. A writesize > 1 is an indication of an ECC-ed flash. Signed-off-by: Pratyush Yadav Reviewed-by: Tudor Ambarus Signed-off-by: Richard Weinberger