In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix kmemleak warning for percpu hashmap
Vlad Poenaru reported the following kmemleak issue:
unreferenced object 0x606fd7c44ac8 (size 32):
backtrace (crc 0):
pcpu_alloc_noprof+0x730/0xeb0
bpf_map_alloc_percpu+0x69/0xc0
prealloc_init+0x9d/0x1b0
htab_map_alloc+0x363/0x510
map_create+0x215/0x3a0
__sys_bpf+0x16b/0x3e0
__x64_sys_bpf+0x18/0x20
do_syscall_64+0x7b/0x150
entry_SYSCALL_64_after_hwframe+0x4b/0x53
Further investigation shows the reason is due to not 8-byte aligned
store of percpu pointer in htab_elem_set_ptr():
*(void __percpu **)(l->key + key_size) = pptr;
Note that the whole htab_elem alignment is 8 (for x86_64). If the key_size
is 4, that means pptr is stored in a location which is 4 byte aligned but
not 8 byte aligned. In mm/kmemleak.c, scan_block() scans the memory based
on 8 byte stride, so it won't detect above pptr, hence reporting the memory
leak.
In htab_map_alloc(), we already have
htab->elem_size = sizeof(struct htab_elem) +
round_up(htab->map.key_size, 8);
if (percpu)
htab->elem_size += sizeof(void *);
else
htab->elem_size += round_up(htab->map.value_size, 8);
So storing pptr with 8-byte alignment won't cause any problem and can fix
kmemleak too.
The issue can be reproduced with bpf selftest as well:
1. Enable CONFIG_DEBUG_KMEMLEAK config
2. Add a getchar() before skel destroy in test_hash_map() in prog_tests/for_each.c.
The purpose is to keep map available so kmemleak can be detected.
3. run './test_progs -t for_each/hash_map &' and a kmemleak should be reported.
In the Linux kernel, the following vulnerability has been resolved:
driver core: fix potential NULL pointer dereference in dev_uevent()
If userspace reads "uevent" device attribute at the same time as another
threads unbinds the device from its driver, change to dev->driver from a
valid pointer to NULL may result in crash. Fix this by using READ_ONCE()
when fetching the pointer, and take bus' drivers klist lock to make sure
driver instance will not disappear while we access it.
Use WRITE_ONCE() when setting the driver pointer to ensure there is no
tearing.
In the Linux kernel, the following vulnerability has been resolved:
scsi: target: Fix WRITE_SAME No Data Buffer crash
In newer version of the SBC specs, we have a NDOB bit that indicates there
is no data buffer that gets written out. If this bit is set using commands
like "sg_write_same --ndob" we will crash in target_core_iblock/file's
execute_write_same handlers when we go to access the se_cmd->t_data_sg
because its NULL.
This patch adds a check for the NDOB bit in the common WRITE SAME code
because we don't support it. And, it adds a check for zero SG elements in
each handler in case the initiator tries to send a normal WRITE SAME with
no data buffer.
In the Linux kernel, the following vulnerability has been resolved:
scsi: core: Remove the /proc/scsi/${proc_name} directory earlier
Remove the /proc/scsi/${proc_name} directory earlier to fix a race
condition between unloading and reloading kernel modules. This fixes a bug
introduced in 2009 by commit 77c019768f06 ("[SCSI] fix /proc memory leak in
the SCSI core").
Fix the following kernel warning:
proc_dir_entry 'scsi/scsi_debug' already registered
WARNING: CPU: 19 PID: 27986 at fs/proc/generic.c:376 proc_register+0x27d/0x2e0
Call Trace:
proc_mkdir+0xb5/0xe0
scsi_proc_hostdir_add+0xb5/0x170
scsi_host_alloc+0x683/0x6c0
sdebug_driver_probe+0x6b/0x2d0 [scsi_debug]
really_probe+0x159/0x540
__driver_probe_device+0xdc/0x230
driver_probe_device+0x4f/0x120
__device_attach_driver+0xef/0x180
bus_for_each_drv+0xe5/0x130
__device_attach+0x127/0x290
device_initial_probe+0x17/0x20
bus_probe_device+0x110/0x130
device_add+0x673/0xc80
device_register+0x1e/0x30
sdebug_add_host_helper+0x1a7/0x3b0 [scsi_debug]
scsi_debug_init+0x64f/0x1000 [scsi_debug]
do_one_initcall+0xd7/0x470
do_init_module+0xe7/0x330
load_module+0x122a/0x12c0
__do_sys_finit_module+0x124/0x1a0
__x64_sys_finit_module+0x46/0x50
do_syscall_64+0x38/0x80
entry_SYSCALL_64_after_hwframe+0x46/0xb0
In the Linux kernel, the following vulnerability has been resolved:
fs: prevent out-of-bounds array speculation when closing a file descriptor
Google-Bug-Id: 114199369
In the Linux kernel, the following vulnerability has been resolved:
ext4: zero i_disksize when initializing the bootloader inode
If the boot loader inode has never been used before, the
EXT4_IOC_SWAP_BOOT inode will initialize it, including setting the
i_size to 0. However, if the "never before used" boot loader has a
non-zero i_size, then i_disksize will be non-zero, and the
inconsistency between i_size and i_disksize can trigger a kernel
warning:
WARNING: CPU: 0 PID: 2580 at fs/ext4/file.c:319
CPU: 0 PID: 2580 Comm: bb Not tainted 6.3.0-rc1-00004-g703695902cfa
RIP: 0010:ext4_file_write_iter+0xbc7/0xd10
Call Trace:
vfs_write+0x3b1/0x5c0
ksys_write+0x77/0x160
__x64_sys_write+0x22/0x30
do_syscall_64+0x39/0x80
Reproducer:
1. create corrupted image and mount it:
mke2fs -t ext4 /tmp/foo.img 200
debugfs -wR "sif <5> size 25700" /tmp/foo.img
mount -t ext4 /tmp/foo.img /mnt
cd /mnt
echo 123 > file
2. Run the reproducer program:
posix_memalign(&buf, 1024, 1024)
fd = open("file", O_RDWR | O_DIRECT);
ioctl(fd, EXT4_IOC_SWAP_BOOT);
write(fd, buf, 1024);
Fix this by setting i_disksize as well as i_size to zero when
initiaizing the boot loader inode.
In the Linux kernel, the following vulnerability has been resolved:
net/iucv: Fix size of interrupt data
iucv_irq_data needs to be 4 bytes larger.
These bytes are not used by the iucv module, but written by
the z/VM hypervisor in case a CPU is deconfigured.
Reported as:
BUG dma-kmalloc-64 (Not tainted): kmalloc Redzone overwritten
-----------------------------------------------------------------------------
0x0000000000400564-0x0000000000400567 @offset=1380. First byte 0x80 instead of 0xcc
Allocated in iucv_cpu_prepare+0x44/0xd0 age=167839 cpu=2 pid=1
__kmem_cache_alloc_node+0x166/0x450
kmalloc_node_trace+0x3a/0x70
iucv_cpu_prepare+0x44/0xd0
cpuhp_invoke_callback+0x156/0x2f0
cpuhp_issue_call+0xf0/0x298
__cpuhp_setup_state_cpuslocked+0x136/0x338
__cpuhp_setup_state+0xf4/0x288
iucv_init+0xf4/0x280
do_one_initcall+0x78/0x390
do_initcalls+0x11a/0x140
kernel_init_freeable+0x25e/0x2a0
kernel_init+0x2e/0x170
__ret_from_fork+0x3c/0x58
ret_from_fork+0xa/0x40
Freed in iucv_init+0x92/0x280 age=167839 cpu=2 pid=1
__kmem_cache_free+0x308/0x358
iucv_init+0x92/0x280
do_one_initcall+0x78/0x390
do_initcalls+0x11a/0x140
kernel_init_freeable+0x25e/0x2a0
kernel_init+0x2e/0x170
__ret_from_fork+0x3c/0x58
ret_from_fork+0xa/0x40
Slab 0x0000037200010000 objects=32 used=30 fp=0x0000000000400640 flags=0x1ffff00000010200(slab|head|node=0|zone=0|
Object 0x0000000000400540 @offset=1344 fp=0x0000000000000000
Redzone 0000000000400500: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc ................
Redzone 0000000000400510: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc ................
Redzone 0000000000400520: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc ................
Redzone 0000000000400530: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc ................
Object 0000000000400540: 00 01 00 03 00 00 00 00 00 00 00 00 00 00 00 00 ................
Object 0000000000400550: f3 86 81 f2 f4 82 f8 82 f0 f0 f0 f0 f0 f0 f0 f2 ................
Object 0000000000400560: 00 00 00 00 80 00 00 00 cc cc cc cc cc cc cc cc ................
Object 0000000000400570: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc ................
Redzone 0000000000400580: cc cc cc cc cc cc cc cc ........
Padding 00000000004005d4: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZZZZZ
Padding 00000000004005e4: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZZZZZ
Padding 00000000004005f4: 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZZZZZ
CPU: 6 PID: 121030 Comm: 116-pai-crypto. Not tainted 6.3.0-20230221.rc0.git4.99b8246b2d71.300.fc37.s390x+debug #1
Hardware name: IBM 3931 A01 704 (z/VM 7.3.0)
Call Trace:
[<000000032aa034ec>] dump_stack_lvl+0xac/0x100
[<0000000329f5a6cc>] check_bytes_and_report+0x104/0x140
[<0000000329f5aa78>] check_object+0x370/0x3c0
[<0000000329f5ede6>] free_debug_processing+0x15e/0x348
[<0000000329f5f06a>] free_to_partial_list+0x9a/0x2f0
[<0000000329f5f4a4>] __slab_free+0x1e4/0x3a8
[<0000000329f61768>] __kmem_cache_free+0x308/0x358
[<000000032a91465c>] iucv_cpu_dead+0x6c/0x88
[<0000000329c2fc66>] cpuhp_invoke_callback+0x156/0x2f0
[<000000032aa062da>] _cpu_down.constprop.0+0x22a/0x5e0
[<0000000329c3243e>] cpu_device_down+0x4e/0x78
[<000000032a61dee0>] device_offline+0xc8/0x118
[<000000032a61e048>] online_store+0x60/0xe0
[<000000032a08b6b0>] kernfs_fop_write_iter+0x150/0x1e8
[<0000000329fab65c>] vfs_write+0x174/0x360
[<0000000329fab9fc>] ksys_write+0x74/0x100
[<000000032aa03a5a>] __do_syscall+0x1da/0x208
[<000000032aa177b2>] system_call+0x82/0xb0
INFO: lockdep is turned off.
FIX dma-kmalloc-64: Restoring kmalloc Redzone 0x0000000000400564-0x0000000000400567=0xcc
FIX dma-kmalloc-64: Object at 0x0000000000400540 not freed
In the Linux kernel, the following vulnerability has been resolved:
ext4: update s_journal_inum if it changes after journal replay
When mounting a crafted ext4 image, s_journal_inum may change after journal
replay, which is obviously unreasonable because we have successfully loaded
and replayed the journal through the old s_journal_inum. And the new
s_journal_inum bypasses some of the checks in ext4_get_journal(), which
may trigger a null pointer dereference problem. So if s_journal_inum
changes after the journal replay, we ignore the change, and rewrite the
current journal_inum to the superblock.
In the Linux kernel, the following vulnerability has been resolved:
powerpc/iommu: fix memory leak with using debugfs_lookup()
When calling debugfs_lookup() the result must have dput() called on it,
otherwise the memory will leak over time. To make things simpler, just
call debugfs_lookup_and_remove() instead which handles all of the logic
at once.