Archivos mensuales: septiembre 2024

In the Linux kernel, the following vulnerability has been resolved:

riscv: misaligned: Restrict user access to kernel memory

raw_copy_{to,from}_user() do not call access_ok(), so this code allowed
userspace to access any virtual memory address.

In the Linux kernel, the following vulnerability has been resolved:

btrfs: fix race between direct IO write and fsync when using same fd

If we have 2 threads that are using the same file descriptor and one of
them is doing direct IO writes while the other is doing fsync, we have a
race where we can end up either:

1) Attempt a fsync without holding the inode's lock, triggering an
assertion failures when assertions are enabled;

2) Do an invalid memory access from the fsync task because the file private
points to memory allocated on stack by the direct IO task and it may be
used by the fsync task after the stack was destroyed.

The race happens like this:

1) A user space program opens a file descriptor with O_DIRECT;

2) The program spawns 2 threads using libpthread for example;

3) One of the threads uses the file descriptor to do direct IO writes,
while the other calls fsync using the same file descriptor.

4) Call task A the thread doing direct IO writes and task B the thread
doing fsyncs;

5) Task A does a direct IO write, and at btrfs_direct_write() sets the
file's private to an on stack allocated private with the member
'fsync_skip_inode_lock' set to true;

6) Task B enters btrfs_sync_file() and sees that there's a private
structure associated to the file which has 'fsync_skip_inode_lock' set
to true, so it skips locking the inode's VFS lock;

7) Task A completes the direct IO write, and resets the file's private to
NULL since it had no prior private and our private was stack allocated.
Then it unlocks the inode's VFS lock;

8) Task B enters btrfs_get_ordered_extents_for_logging(), then the
assertion that checks the inode's VFS lock is held fails, since task B
never locked it and task A has already unlocked it.

The stack trace produced is the following:

assertion failed: inode_is_locked(&inode->vfs_inode), in fs/btrfs/ordered-data.c:983
————[ cut here ]————
kernel BUG at fs/btrfs/ordered-data.c:983!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP PTI
CPU: 9 PID: 5072 Comm: worker Tainted: G U OE 6.10.5-1-default #1 openSUSE Tumbleweed 69f48d427608e1c09e60ea24c6c55e2ca1b049e8
Hardware name: Acer Predator PH315-52/Covini_CFS, BIOS V1.12 07/28/2020
RIP: 0010:btrfs_get_ordered_extents_for_logging.cold+0x1f/0x42 [btrfs]
Code: 50 d6 86 c0 e8 (…)
RSP: 0018:ffff9e4a03dcfc78 EFLAGS: 00010246
RAX: 0000000000000054 RBX: ffff9078a9868e98 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff907dce4a7800 RDI: ffff907dce4a7800
RBP: ffff907805518800 R08: 0000000000000000 R09: ffff9e4a03dcfb38
R10: ffff9e4a03dcfb30 R11: 0000000000000003 R12: ffff907684ae7800
R13: 0000000000000001 R14: ffff90774646b600 R15: 0000000000000000
FS: 00007f04b96006c0(0000) GS:ffff907dce480000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f32acbfc000 CR3: 00000001fd4fa005 CR4: 00000000003726f0
Call Trace:

? __die_body.cold+0x14/0x24
? die+0x2e/0x50
? do_trap+0xca/0x110
? do_error_trap+0x6a/0x90
? btrfs_get_ordered_extents_for_logging.cold+0x1f/0x42 [btrfs bb26272d49b4cdc847cf3f7faadd459b62caee9a]
? exc_invalid_op+0x50/0x70
? btrfs_get_ordered_extents_for_logging.cold+0x1f/0x42 [btrfs bb26272d49b4cdc847cf3f7faadd459b62caee9a]
? asm_exc_invalid_op+0x1a/0x20
? btrfs_get_ordered_extents_for_logging.cold+0x1f/0x42 [btrfs bb26272d49b4cdc847cf3f7faadd459b62caee9a]
? btrfs_get_ordered_extents_for_logging.cold+0x1f/0x42 [btrfs bb26272d49b4cdc847cf3f7faadd459b62caee9a]
btrfs_sync_file+0x21a/0x4d0 [btrfs bb26272d49b4cdc847cf3f7faadd459b62caee9a]
? __seccomp_filter+0x31d/0x4f0
__x64_sys_fdatasync+0x4f/0x90
do_syscall_64+0x82/0x160
? do_futex+0xcb/0x190
? __x64_sys_futex+0x10e/0x1d0
? switch_fpu_return+0x4f/0xd0
? syscall_exit_to_user_mode+0x72/0x220
? do_syscall_64+0x8e/0x160
? syscall_exit_to_user_mod
—truncated—

In the Linux kernel, the following vulnerability has been resolved:

smb: client: fix double put of @cfile in smb2_rename_path()

If smb2_set_path_attr() is called with a valid @cfile and returned
-EINVAL, we need to call cifs_get_writable_path() again as the
reference of @cfile was already dropped by previous smb2_compound_op()
call.

In the Linux kernel, the following vulnerability has been resolved:

ublk_drv: fix NULL pointer dereference in ublk_ctrl_start_recovery()

When two UBLK_CMD_START_USER_RECOVERY commands are submitted, the
first one sets 'ubq->ubq_daemon' to NULL, and the second one triggers
WARN in ublk_queue_reinit() and subsequently a NULL pointer dereference
issue.

Fix it by adding the check in ublk_ctrl_start_recovery() and return
immediately in case of zero 'ub->nr_queues_ready'.

BUG: kernel NULL pointer dereference, address: 0000000000000028
RIP: 0010:ublk_ctrl_start_recovery.constprop.0+0x82/0x180
Call Trace:

? __die+0x20/0x70
? page_fault_oops+0x75/0x170
? exc_page_fault+0x64/0x140
? asm_exc_page_fault+0x22/0x30
? ublk_ctrl_start_recovery.constprop.0+0x82/0x180
ublk_ctrl_uring_cmd+0x4f7/0x6c0
? pick_next_task_idle+0x26/0x40
io_uring_cmd+0x9a/0x1b0
io_issue_sqe+0x193/0x3f0
io_wq_submit_work+0x9b/0x390
io_worker_handle_work+0x165/0x360
io_wq_worker+0xcb/0x2f0
? finish_task_switch.isra.0+0x203/0x290
? finish_task_switch.isra.0+0x203/0x290
? __pfx_io_wq_worker+0x10/0x10
ret_from_fork+0x2d/0x50
? __pfx_io_wq_worker+0x10/0x10
ret_from_fork_asm+0x1a/0x30

In the Linux kernel, the following vulnerability has been resolved:

drm/amd/display: Fix incorrect size calculation for loop

[WHY]
fe_clk_en has size of 5 but sizeof(fe_clk_en) has byte size 20 which is
lager than the array size.

[HOW]
Divide byte size 20 by its element size.

This fixes 2 OVERRUN issues reported by Coverity.

In the Linux kernel, the following vulnerability has been resolved:

drm/amd/display: Check index for aux_rd_interval before using

aux_rd_interval has size of 7 and should be checked.

This fixes 3 OVERRUN and 1 INTEGER_OVERFLOW issues reported by Coverity.

In the Linux kernel, the following vulnerability has been resolved:

drm/amd/display: Add otg_master NULL check within resource_log_pipe_topology_update

[Why]
Coverity reports NULL_RETURN warning.

[How]
Add otg_master NULL check.

In the Linux kernel, the following vulnerability has been resolved:

drm/amd/display: Ensure index calculation will not overflow

[WHY & HOW]
Make sure vmid0p72_idx, vnom0p8_idx and vmax0p9_idx calculation will
never overflow and exceess array size.

This fixes 3 OVERRUN and 1 INTEGER_OVERFLOW issues reported by Coverity.

OMFLOW from The SYSCOM Group has a vulnerability involving the exposure of sensitive data. This allows remote attackers who have logged into the system to obtain password hashes of all users and administrators.

Hidden functionality issue in multiple digital video recorders provided by TAKENAKA ENGINEERING CO., LTD. allows a remote authenticated attacker to execute an arbitrary OS command on the device or alter the device settings.