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3 commits

Author SHA1 Message Date
Wang Yong
b131b91878 jffs2: Fix potential illegal address access in jffs2_free_inode
[ Upstream commit af9a8730ddb6a4b2edd779ccc0aceb994d616830 ]

During the stress testing of the jffs2 file system,the following
abnormal printouts were found:
[ 2430.649000] Unable to handle kernel paging request at virtual address 0069696969696948
[ 2430.649622] Mem abort info:
[ 2430.649829]   ESR = 0x96000004
[ 2430.650115]   EC = 0x25: DABT (current EL), IL = 32 bits
[ 2430.650564]   SET = 0, FnV = 0
[ 2430.650795]   EA = 0, S1PTW = 0
[ 2430.651032]   FSC = 0x04: level 0 translation fault
[ 2430.651446] Data abort info:
[ 2430.651683]   ISV = 0, ISS = 0x00000004
[ 2430.652001]   CM = 0, WnR = 0
[ 2430.652558] [0069696969696948] address between user and kernel address ranges
[ 2430.653265] Internal error: Oops: 96000004 [#1] PREEMPT SMP
[ 2430.654512] CPU: 2 PID: 20919 Comm: cat Not tainted 5.15.25-g512f31242bf6 #33
[ 2430.655008] Hardware name: linux,dummy-virt (DT)
[ 2430.655517] pstate: 20000005 (nzCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 2430.656142] pc : kfree+0x78/0x348
[ 2430.656630] lr : jffs2_free_inode+0x24/0x48
[ 2430.657051] sp : ffff800009eebd10
[ 2430.657355] x29: ffff800009eebd10 x28: 0000000000000001 x27: 0000000000000000
[ 2430.658327] x26: ffff000038f09d80 x25: 0080000000000000 x24: ffff800009d38000
[ 2430.658919] x23: 5a5a5a5a5a5a5a5a x22: ffff000038f09d80 x21: ffff8000084f0d14
[ 2430.659434] x20: ffff0000bf9a6ac0 x19: 0169696969696940 x18: 0000000000000000
[ 2430.659969] x17: ffff8000b6506000 x16: ffff800009eec000 x15: 0000000000004000
[ 2430.660637] x14: 0000000000000000 x13: 00000001000820a1 x12: 00000000000d1b19
[ 2430.661345] x11: 0004000800000000 x10: 0000000000000001 x9 : ffff8000084f0d14
[ 2430.662025] x8 : ffff0000bf9a6b40 x7 : ffff0000bf9a6b48 x6 : 0000000003470302
[ 2430.662695] x5 : ffff00002e41dcc0 x4 : ffff0000bf9aa3b0 x3 : 0000000003470342
[ 2430.663486] x2 : 0000000000000000 x1 : ffff8000084f0d14 x0 : fffffc0000000000
[ 2430.664217] Call trace:
[ 2430.664528]  kfree+0x78/0x348
[ 2430.664855]  jffs2_free_inode+0x24/0x48
[ 2430.665233]  i_callback+0x24/0x50
[ 2430.665528]  rcu_do_batch+0x1ac/0x448
[ 2430.665892]  rcu_core+0x28c/0x3c8
[ 2430.666151]  rcu_core_si+0x18/0x28
[ 2430.666473]  __do_softirq+0x138/0x3cc
[ 2430.666781]  irq_exit+0xf0/0x110
[ 2430.667065]  handle_domain_irq+0x6c/0x98
[ 2430.667447]  gic_handle_irq+0xac/0xe8
[ 2430.667739]  call_on_irq_stack+0x28/0x54
The parameter passed to kfree was 5a5a5a5a, which corresponds to the target field of
the jffs_inode_info structure. It was found that all variables in the jffs_inode_info
structure were 5a5a5a5a, except for the first member sem. It is suspected that these
variables are not initialized because they were set to 5a5a5a5a during memory testing,
which is meant to detect uninitialized memory.The sem variable is initialized in the
function jffs2_i_init_once, while other members are initialized in
the function jffs2_init_inode_info.

The function jffs2_init_inode_info is called after iget_locked,
but in the iget_locked function, the destroy_inode process is triggered,
which releases the inode and consequently, the target member of the inode
is not initialized.In concurrent high pressure scenarios, iget_locked
may enter the destroy_inode branch as described in the code.

Since the destroy_inode functionality of jffs2 only releases the target,
the fix method is to set target to NULL in jffs2_i_init_once.

Signed-off-by: Wang Yong <wang.yong12@zte.com.cn>
Reviewed-by: Lu Zhongjun <lu.zhongjun@zte.com.cn>
Reviewed-by: Yang Tao <yang.tao172@zte.com.cn>
Cc: Xu Xin <xu.xin16@zte.com.cn>
Cc: Yang Yang <yang.yang29@zte.com.cn>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 14:19:41 +01:00
Ilya Denisyev
cf88d14d52 jffs2: prevent xattr node from overflowing the eraseblock
[ Upstream commit c6854e5a267c28300ff045480b5a7ee7f6f1d913 ]

Add a check to make sure that the requested xattr node size is no larger
than the eraseblock minus the cleanmarker.

Unlike the usual inode nodes, the xattr nodes aren't split into parts
and spread across multiple eraseblocks, which means that a xattr node
must not occupy more than one eraseblock. If the requested xattr value is
too large, the xattr node can spill onto the next eraseblock, overwriting
the nodes and causing errors such as:

jffs2: argh. node added in wrong place at 0x0000b050(2)
jffs2: nextblock 0x0000a000, expected at 0000b00c
jffs2: error: (823) do_verify_xattr_datum: node CRC failed at 0x01e050,
read=0xfc892c93, calc=0x000000
jffs2: notice: (823) jffs2_get_inode_nodes: Node header CRC failed
at 0x01e00c. {848f,2fc4,0fef511f,59a3d171}
jffs2: Node at 0x0000000c with length 0x00001044 would run over the
end of the erase block
jffs2: Perhaps the file system was created with the wrong erase size?
jffs2: jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found
at 0x00000010: 0x1044 instead

This breaks the filesystem and can lead to KASAN crashes such as:

BUG: KASAN: slab-out-of-bounds in jffs2_sum_add_kvec+0x125e/0x15d0
Read of size 4 at addr ffff88802c31e914 by task repro/830
CPU: 0 PID: 830 Comm: repro Not tainted 6.9.0-rc3+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS Arch Linux 1.16.3-1-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xc6/0x120
 print_report+0xc4/0x620
 ? __virt_addr_valid+0x308/0x5b0
 kasan_report+0xc1/0xf0
 ? jffs2_sum_add_kvec+0x125e/0x15d0
 ? jffs2_sum_add_kvec+0x125e/0x15d0
 jffs2_sum_add_kvec+0x125e/0x15d0
 jffs2_flash_direct_writev+0xa8/0xd0
 jffs2_flash_writev+0x9c9/0xef0
 ? __x64_sys_setxattr+0xc4/0x160
 ? do_syscall_64+0x69/0x140
 ? entry_SYSCALL_64_after_hwframe+0x76/0x7e
 [...]

Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

Fixes: aa98d7cf59b5 ("[JFFS2][XATTR] XATTR support on JFFS2 (version. 5)")
Signed-off-by: Ilya Denisyev <dev@elkcl.ru>
Link: https://lore.kernel.org/r/20240412155357.237803-1-dev@elkcl.ru
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:26:52 +01:00
Gabriel2392
7ed7ee9edf Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00