Vulnerabilities > CVE-2024-35990 - Improper Locking vulnerability in Linux Kernel
Summary
In the Linux kernel, the following vulnerability has been resolved: dma: xilinx_dpdma: Fix locking There are several places where either chan->lock or chan->vchan.lock was not held. Add appropriate locking. This fixes lockdep warnings like [ 31.077578] ------------[ cut here ]------------ [ 31.077831] WARNING: CPU: 2 PID: 40 at drivers/dma/xilinx/xilinx_dpdma.c:834 xilinx_dpdma_chan_queue_transfer+0x274/0x5e0 [ 31.077953] Modules linked in: [ 31.078019] CPU: 2 PID: 40 Comm: kworker/u12:1 Not tainted 6.6.20+ #98 [ 31.078102] Hardware name: xlnx,zynqmp (DT) [ 31.078169] Workqueue: events_unbound deferred_probe_work_func [ 31.078272] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 31.078377] pc : xilinx_dpdma_chan_queue_transfer+0x274/0x5e0 [ 31.078473] lr : xilinx_dpdma_chan_queue_transfer+0x270/0x5e0 [ 31.078550] sp : ffffffc083bb2e10 [ 31.078590] x29: ffffffc083bb2e10 x28: 0000000000000000 x27: ffffff880165a168 [ 31.078754] x26: ffffff880164e920 x25: ffffff880164eab8 x24: ffffff880164d480 [ 31.078920] x23: ffffff880165a148 x22: ffffff880164e988 x21: 0000000000000000 [ 31.079132] x20: ffffffc082aa3000 x19: ffffff880164e880 x18: 0000000000000000 [ 31.079295] x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 [ 31.079453] x14: 0000000000000000 x13: ffffff8802263dc0 x12: 0000000000000001 [ 31.079613] x11: 0001ffc083bb2e34 x10: 0001ff880164e98f x9 : 0001ffc082aa3def [ 31.079824] x8 : 0001ffc082aa3dec x7 : 0000000000000000 x6 : 0000000000000516 [ 31.079982] x5 : ffffffc7f8d43000 x4 : ffffff88003c9c40 x3 : ffffffffffffffff [ 31.080147] x2 : ffffffc7f8d43000 x1 : 00000000000000c0 x0 : 0000000000000000 [ 31.080307] Call trace: [ 31.080340] xilinx_dpdma_chan_queue_transfer+0x274/0x5e0 [ 31.080518] xilinx_dpdma_issue_pending+0x11c/0x120 [ 31.080595] zynqmp_disp_layer_update+0x180/0x3ac [ 31.080712] zynqmp_dpsub_plane_atomic_update+0x11c/0x21c [ 31.080825] drm_atomic_helper_commit_planes+0x20c/0x684 [ 31.080951] drm_atomic_helper_commit_tail+0x5c/0xb0 [ 31.081139] commit_tail+0x234/0x294 [ 31.081246] drm_atomic_helper_commit+0x1f8/0x210 [ 31.081363] drm_atomic_commit+0x100/0x140 [ 31.081477] drm_client_modeset_commit_atomic+0x318/0x384 [ 31.081634] drm_client_modeset_commit_locked+0x8c/0x24c [ 31.081725] drm_client_modeset_commit+0x34/0x5c [ 31.081812] __drm_fb_helper_restore_fbdev_mode_unlocked+0x104/0x168 [ 31.081899] drm_fb_helper_set_par+0x50/0x70 [ 31.081971] fbcon_init+0x538/0xc48 [ 31.082047] visual_init+0x16c/0x23c [ 31.082207] do_bind_con_driver.isra.0+0x2d0/0x634 [ 31.082320] do_take_over_console+0x24c/0x33c [ 31.082429] do_fbcon_takeover+0xbc/0x1b0 [ 31.082503] fbcon_fb_registered+0x2d0/0x34c [ 31.082663] register_framebuffer+0x27c/0x38c [ 31.082767] __drm_fb_helper_initial_config_and_unlock+0x5c0/0x91c [ 31.082939] drm_fb_helper_initial_config+0x50/0x74 [ 31.083012] drm_fbdev_dma_client_hotplug+0xb8/0x108 [ 31.083115] drm_client_register+0xa0/0xf4 [ 31.083195] drm_fbdev_dma_setup+0xb0/0x1cc [ 31.083293] zynqmp_dpsub_drm_init+0x45c/0x4e0 [ 31.083431] zynqmp_dpsub_probe+0x444/0x5e0 [ 31.083616] platform_probe+0x8c/0x13c [ 31.083713] really_probe+0x258/0x59c [ 31.083793] __driver_probe_device+0xc4/0x224 [ 31.083878] driver_probe_device+0x70/0x1c0 [ 31.083961] __device_attach_driver+0x108/0x1e0 [ 31.084052] bus_for_each_drv+0x9c/0x100 [ 31.084125] __device_attach+0x100/0x298 [ 31.084207] device_initial_probe+0x14/0x20 [ 31.084292] bus_probe_device+0xd8/0xdc [ 31.084368] deferred_probe_work_func+0x11c/0x180 [ 31.084451] process_one_work+0x3ac/0x988 [ 31.084643] worker_thread+0x398/0x694 [ 31.084752] kthread+0x1bc/0x1c0 [ 31.084848] ret_from_fork+0x10/0x20 [ 31.084932] irq event stamp: 64549 [ 31.084970] hardirqs last enabled at (64548): [<ffffffc081adf35c>] _raw_spin_unlock_irqrestore+0x80/0x90 [ 31.085157] ---truncated---
Vulnerable Configurations
Common Weakness Enumeration (CWE)
Common Attack Pattern Enumeration and Classification (CAPEC)
- Leveraging Race Conditions This attack targets a race condition occurring when multiple processes access and manipulate the same resource concurrently and the outcome of the execution depends on the particular order in which the access takes place. The attacker can leverage a race condition by "running the race", modifying the resource and modifying the normal execution flow. For instance a race condition can occur while accessing a file, the attacker can trick the system by replacing the original file with his version and cause the system to read the malicious file.
- Leveraging Race Conditions via Symbolic Links This attack leverages the use of symbolic links (Symlinks) in order to write to sensitive files. An attacker can create a Symlink link to a target file not otherwise accessible to her. When the privileged program tries to create a temporary file with the same name as the Symlink link, it will actually write to the target file pointed to by the attackers' Symlink link. If the attacker can insert malicious content in the temporary file she will be writing to the sensitive file by using the Symlink. The race occurs because the system checks if the temporary file exists, then creates the file. The attacker would typically create the Symlink during the interval between the check and the creation of the temporary file.
References
- https://git.kernel.org/stable/c/fcdd5bb4a8c81c64c1334d7e0aba41a8829a24de
- https://git.kernel.org/stable/c/0ccac964520a6f19e355652c8ca38af2a7f27076
- https://git.kernel.org/stable/c/8bf574183282d219cfa991f7df37aad491d74c11
- https://git.kernel.org/stable/c/8e3c94767cad5150198e4337c8b91f3bb068e14b
- https://git.kernel.org/stable/c/c660be571609e03e7d5972343536a736fcb31557
- https://git.kernel.org/stable/c/244296cc3a155199a8b080d19e645d7d49081a38