In the Linux kernel, the following vulnerability has been resolved:
lib: cpu_rmap: Avoid use after free on rmap->obj array entries
When calling irq_set_affinity_notifier() with NULL at the notify
argument, it will cause freeing of the glue pointer in the
corresponding array entry but will leave the pointer in the array. A
subsequent call to free_irq_cpu_rmap() will try to free this entry again
leading to possible use after free.
Fix that by setting NULL to the array entry and checking that we have
non-zero at the array entry when iterating over the array in
free_irq_cpu_rmap().
The current code does not suffer from this since there are no cases
where irq_set_affinity_notifier(irq, NULL) (note the NULL passed for the
notify arg) is called, followed by a call to free_irq_cpu_rmap() so we
don't hit and issue. Subsequent patches in this series excersize this
flow, hence the required fix.
In the Linux kernel, the following vulnerability has been resolved:
IB/hfi1: Fix possible panic during hotplug remove
During hotplug remove it is possible that the update counters work
might be pending, and may run after memory has been freed.
Cancel the update counters work before freeing memory.
In the Linux kernel, the following vulnerability has been resolved:
ubi: ubi_wl_put_peb: Fix infinite loop when wear-leveling work failed
Following process will trigger an infinite loop in ubi_wl_put_peb():
ubifs_bgt ubi_bgt
ubifs_leb_unmap
ubi_leb_unmap
ubi_eba_unmap_leb
ubi_wl_put_peb wear_leveling_worker
e1 = rb_entry(rb_first(&ubi->used)
e2 = get_peb_for_wl(ubi)
ubi_io_read_vid_hdr // return err (flash fault)
out_error:
ubi->move_from = ubi->move_to = NULL
wl_entry_destroy(ubi, e1)
ubi->lookuptbl[e->pnum] = NULL
retry:
e = ubi->lookuptbl[pnum]; // return NULL
if (e == ubi->move_from) { // NULL == NULL gets true
goto retry; // infinite loop !!!
$ top
PID USER PR NI VIRT RES SHR S %CPU %MEM COMMAND
7676 root 20 0 0 0 0 R 100.0 0.0 ubifs_bgt0_0
Fix it by:
1) Letting ubi_wl_put_peb() returns directly if wearl leveling entry has
been removed from 'ubi->lookuptbl'.
2) Using 'ubi->wl_lock' protecting wl entry deletion to preventing an
use-after-free problem for wl entry in ubi_wl_put_peb().
Fetch a reproducer in [Link].
In the Linux kernel, the following vulnerability has been resolved:
FS: JFS: Fix null-ptr-deref Read in txBegin
Syzkaller reported an issue where txBegin may be called
on a superblock in a read-only mounted filesystem which leads
to NULL pointer deref. This could be solved by checking if
the filesystem is read-only before calling txBegin, and returning
with appropiate error code.
In the Linux kernel, the following vulnerability has been resolved:
media: cx23885: Fix a null-ptr-deref bug in buffer_prepare() and buffer_finish()
When the driver calls cx23885_risc_buffer() to prepare the buffer, the
function call dma_alloc_coherent may fail, resulting in a empty buffer
risc->cpu. Later when we free the buffer or access the buffer, null ptr
deref is triggered.
This bug is similar to the following one:
https://git.linuxtv.org/media_stage.git/commit/?id=2b064d91440b33fba5b452f2d1b31f13ae911d71.
We believe the bug can be also dynamically triggered from user side.
Similarly, we fix this by checking the return value of cx23885_risc_buffer()
and the value of risc->cpu before buffer free.
In the Linux kernel, the following vulnerability has been resolved:
scsi: qla4xxx: Add length check when parsing nlattrs
There are three places that qla4xxx parses nlattrs:
- qla4xxx_set_chap_entry()
- qla4xxx_iface_set_param()
- qla4xxx_sysfs_ddb_set_param()
and each of them directly converts the nlattr to specific pointer of
structure without length checking. This could be dangerous as those
attributes are not validated and a malformed nlattr (e.g., length 0) could
result in an OOB read that leaks heap dirty data.
Add the nla_len check before accessing the nlattr data and return EINVAL if
the length check fails.
In the Linux kernel, the following vulnerability has been resolved:
scsi: qla2xxx: Fix potential NULL pointer dereference
Klocwork tool reported 'cur_dsd' may be dereferenced. Add fix to validate
pointer before dereferencing the pointer.