NULL Pointer Dereference

In the Linux kernel, the following vulnerability has been resolved: Revert "drm/gem-framebuffer: Use dma_buf from GEM object instance" This reverts commit cce16fcd7446dcff7480cd9d2b6417075ed81065. The dma_buf field in struct drm_gem_object is not stable over the object instance's lifetime. The field becomes NULL when user space releases the final GEM handle on the buffer object. This resulted in a NULL-pointer deref. Workarounds in commit 5307dce878d4 ("drm/gem: Acquire references on GEM handles for framebuffers") and commit f6bfc9afc751 ("drm/framebuffer: Acquire internal references on GEM handles") only solved the problem partially. They especially don't work for buffer objects without a DRM framebuffer associated. Hence, this revert to going back to using .import_attach->dmabuf. v3: - cc stableShow less

In the Linux kernel, the following vulnerability has been resolved: Revert "drm/gem-dma: Use dma_buf from GEM object instance" This reverts commit e8afa1557f4f963c9a511bd2c6074a941c308685. The dma_buf field in struct drm_gem_object is not stable over the object instance's lifetime. The field becomes NULL when user space releases the final GEM handle on the buffer object. This resulted in a NULL-pointer deref. Workarounds in commit 5307dce878d4 ("drm/gem: Acquire references on GEM handles for framebuffers") and commit f6bfc9afc751 ("drm/framebuffer: Acquire internal references on GEM handles") only solved the problem partially. They especially don't work for buffer objects without a DRM framebuffer associated. Hence, this revert to going back to using .import_attach->dmabuf. v3: - cc stableShow less

In the Linux kernel, the following vulnerability has been resolved: Revert "drm/gem-shmem: Use dma_buf from GEM object instance" This reverts commit 1a148af06000e545e714fe3210af3d77ff903c11. The dma_buf field in struct drm_gem_object is not stable over the object instance's lifetime. The field becomes NULL when user space releases the final GEM handle on the buffer object. This resulted in a NULL-pointer deref. Workarounds in commit 5307dce878d4 ("drm/gem: Acquire references on GEM handles for framebuffers") and commit f6bfc9afc751 ("drm/framebuffer: Acquire internal references on GEM handles") only solved the problem partially. They especially don't work for buffer objects without a DRM framebuffer associated. Hence, this revert to going back to using .import_attach->dmabuf. v3: - cc stableShow less

In the Linux kernel, the following vulnerability has been resolved: regulator: core: fix NULL dereference on unbind due to stale coupling data Failing to reset coupling_desc.n_coupled after freeing coupled_rdevs can lead to NULL pointer dereference when regulators are accessed post-unbind. This can happen during runtime PM or other regulator operations that rely on coupling metadata. For example, on ridesx4, unbinding the 'reg-dummy' platform device triggers a panic in regulator_lock_recursive() due to stale coupling state. Ensure n_coupled is set to 0 to prevent access to invalid pointers.Show less

In the Linux kernel, the following vulnerability has been resolved: can: netlink: can_changelink(): fix NULL pointer deref of struct can_priv::do_set_mode Andrei Lalaev reported a NULL pointer deref when a CAN device is restarted from Bus Off and the driver does not implement the struct can_priv::do_set_mode callback. There are 2 code path that call struct can_priv::do_set_mode: - directly by a manual restart from the user space, via can_changelink() - delayed automatic restart after bus off (deactivated by default) To prevent the NULL pointer deference, refuse a manual restart or configure the automatic restart delay in can_changelink() and report the error via extack to user space. As an additional safety measure let can_restart() return an error if can_priv::do_set_mode is not set instead of dereferencing it unchecked.Show less

In the Linux kernel, the following vulnerability has been resolved: ice: Fix a null pointer dereference in ice_copy_and_init_pkg() Add check for the return value of devm_kmemdup() to prevent potential null pointer dereference.Show less

In the Linux kernel, the following vulnerability has been resolved: gfs2: No more self recovery When a node withdraws and it turns out that it is the only node that has the filesystem mounted, gfs2 currently tries to replay the local journal to bring the filesystem back into a consistent state. Not only is that a very bad idea, it has also never worked because gfs2_recover_func() will refuse to do anything during a withdraw. However, before even getting to this point, gfs2_recover_func() dereferences sdp->sd_jdesc->jd_inode. This was a use-after-free before commit 04133b607a78 ("gfs2: Prevent double iput for journal on error") and is a NULL pointer dereference since then. Simply get rid of self recovery to fix that.Show less

In the Linux kernel, the following vulnerability has been resolved: pinctrl: canaan: k230: add NULL check in DT parse Add a NULL check for the return value of of_get_property() when retrieving the "pinmux" property in the group parser. This avoids a potential NULL pointer dereference if the property is missing from the device tree node. Also fix a typo ("sintenel") in the device ID match table comment, correcting it to "sentinel".Show less

In the Linux kernel, the following vulnerability has been resolved: spi: stm32: Check for cfg availability in stm32_spi_probe The stm32_spi_probe function now includes a check to ensure that the pointer returned by of_device_get_match_data is not NULL before accessing its members. This resolves a warning where a potential NULL pointer dereference could occur when accessing cfg->has_device_mode. Before accessing the 'has_device_mode' member, we verify that 'cfg' is not NULL. If 'cfg' is NULL, an error message is logged. This change ensures that the driver does not attempt to access configuration data if it is not available, thus preventing a potential system crash due to a NULL pointer dereference.Show less

In the Linux kernel, the following vulnerability has been resolved: wifi: rtw89: avoid NULL dereference when RX problematic packet on unsupported 6 GHz band With a quite rare chance, RX report might be problematic to make SW think a packet is received on 6 GHz band even if the chip does not support 6 GHz band actually. Since SW won't initialize stuffs for unsupported bands, NULL dereference will happen then in the sequence, rtw89_vif_rx_stats_iter() -> rtw89_core_cancel_6ghz_probe_tx(). So, add a check to avoid it. The following is a crash log for this case. BUG: kernel NULL pointer dereference, address: 0000000000000032 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 1 PID: 1907 Comm: irq/131-rtw89_p Tainted: G U 6.6.56-05896-g89f5fb0eb30b #1 (HASH:1400 4) Hardware name: Google Telith/Telith, BIOS Google_Telith.15217.747.0 11/12/2024 RIP: 0010:rtw89_vif_rx_stats_iter+0xd2/0x310 [rtw89_core] Code: 4c 89 7d c8 48 89 55 c0 49 8d 44 24 02 48 89 45 b8 45 31 ff eb 11 41 c6 45 3a 01 41 b7 01 4d 8b 6d 00 4d 39 f5 74 42 8b 43 10 <41> 33 45 32 0f b7 4b 14 66 41 33 4d 36 0f b7 c9 09 c1 74 d8 4d 85 RSP: 0018:ffff9f3080138ca0 EFLAGS: 00010246 RAX: 00000000b8bf5770 RBX: ffff91b5e8c639c0 RCX: 0000000000000011 RDX: ffff91b582de1be8 RSI: 0000000000000000 RDI: ffff91b5e8c639e6 RBP: ffff9f3080138d00 R08: 0000000000000000 R09: 0000000000000000 R10: ffff91b59de70000 R11: ffffffffc069be50 R12: ffff91b5e8c639e4 R13: 0000000000000000 R14: ffff91b5828020b8 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff91b8efa40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000032 CR3: 00000002bf838000 CR4: 0000000000750ee0 PKRU: 55555554 Call Trace: <IRQ> ? __die_body+0x68/0xb0 ? page_fault_oops+0x379/0x3e0 ? exc_page_fault+0x4f/0xa0 ? asm_exc_page_fault+0x22/0x30 ? __pfx_rtw89_vif_rx_stats_iter+0x10/0x10 [rtw89_core (HASH:1400 5)] ? rtw89_vif_rx_stats_iter+0xd2/0x310 [rtw89_core (HASH:1400 5)] __iterate_interfaces+0x59/0x110 [mac80211 (HASH:1400 6)] ? __pfx_rtw89_vif_rx_stats_iter+0x10/0x10 [rtw89_core (HASH:1400 5)] ? __pfx_rtw89_vif_rx_stats_iter+0x10/0x10 [rtw89_core (HASH:1400 5)] ieee80211_iterate_active_interfaces_atomic+0x36/0x50 [mac80211 (HASH:1400 6)] rtw89_core_rx_to_mac80211+0xfd/0x1b0 [rtw89_core (HASH:1400 5)] rtw89_core_rx+0x43a/0x980 [rtw89_core (HASH:1400 5)]Show less

In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Check device memory pointer before usage Add a NULL check before accessing device memory to prevent a crash if dev->dm allocation in mlx5_init_once() fails.Show less

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btusb: Fix potential NULL dereference on kmalloc failure Avoid potential NULL pointer dereference by checking the return value of kmalloc and handling allocation failure properly.Show less

In the Linux kernel, the following vulnerability has been resolved: clk: davinci: Add NULL check in davinci_lpsc_clk_register() devm_kasprintf() returns NULL when memory allocation fails. Currently, davinci_lpsc_clk_register() does not check for this case, which results in a NULL pointer dereference. Add NULL check after devm_kasprintf() to prevent this issue and ensuring no resources are left allocated.Show less

In the Linux kernel, the following vulnerability has been resolved: power: supply: cpcap-charger: Fix null check for power_supply_get_by_name In the cpcap_usb_detect() function, the power_supply_get_by_name() function may return `NULL` instead of an error pointer. To prevent potential null pointer dereferences, Added a null check.Show less

In the Linux kernel, the following vulnerability has been resolved: pinmux: fix race causing mux_owner NULL with active mux_usecount commit 5a3e85c3c397 ("pinmux: Use sequential access to access desc->pinmux data") tried to address the issue when two client of the same gpio calls pinctrl_select_state() for the same functionality, was resulting in NULL pointer issue while accessing desc->mux_owner. However, issue was not completely fixed due to the way it was handled and it can still result in the same NULL pointer. The issue occurs due to the following interleaving: cpu0 (process A) cpu1 (process B) pin_request() { pin_free() { mutex_lock() desc->mux_usecount--; //becomes 0 .. mutex_unlock() mutex_lock(desc->mux) desc->mux_usecount++; // becomes 1 desc->mux_owner = owner; mutex_unlock(desc->mux) mutex_lock(desc->mux) desc->mux_owner = NULL; mutex_unlock(desc->mux) This sequence leads to a state where the pin appears to be in use (`mux_usecount == 1`) but has no owner (`mux_owner == NULL`), which can cause NULL pointer on next pin_request on the same pin. Ensure that updates to mux_usecount and mux_owner are performed atomically under the same lock. Only clear mux_owner when mux_usecount reaches zero and no new owner has been assigned.Show less

In the Linux kernel, the following vulnerability has been resolved: fbdev: imxfb: Check fb_add_videomode to prevent null-ptr-deref fb_add_videomode() can fail with -ENOMEM when its internal kmalloc() cannot allocate a struct fb_modelist. If that happens, the modelist stays empty but the driver continues to register. Add a check for its return value to prevent poteintial null-ptr-deref, which is similar to the commit 17186f1f90d3 ("fbdev: Fix do_register_framebuffer to prevent null-ptr-deref in fb_videomode_to_var").Show less

In the Linux kernel, the following vulnerability has been resolved: ALSA: usb: scarlett2: Fix missing NULL check scarlett2_input_select_ctl_info() sets up the string arrays allocated via kasprintf(), but it misses NULL checks, which may lead to NULL dereference Oops. Let's add the proper NULL check.Show less

In the Linux kernel, the following vulnerability has been resolved: md: make rdev_addable usable for rcu mode Our testcase trigger panic: BUG: kernel NULL pointer dereference, address: 00000000000000e0 ... Oops: Oops: 0000 [#1] SMP NOPTI CPU: 2 UID: 0 PID: 85 Comm: kworker/2:1 Not tainted 6.16.0+ #94 PREEMPT(none) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014 Workqueue: md_misc md_start_sync RIP: 0010:rdev_addable+0x4d/0xf0 ... Call Trace: <TASK> md_start_sync+0x329/0x480 process_one_work+0x226/0x6d0 worker_thread+0x19e/0x340 kthread+0x10f/0x250 ret_from_fork+0x14d/0x180 ret_from_fork_asm+0x1a/0x30 </TASK> Modules linked in: raid10 CR2: 00000000000000e0 ---[ end trace 0000000000000000 ]--- RIP: 0010:rdev_addable+0x4d/0xf0 md_spares_need_change in md_start_sync will call rdev_addable which protected by rcu_read_lock/rcu_read_unlock. This rcu context will help protect rdev won't be released, but rdev->mddev will be set to NULL before we call synchronize_rcu in md_kick_rdev_from_array. Fix this by using READ_ONCE and check does rdev->mddev still alive.Show less

In the Linux kernel, the following vulnerability has been resolved: media: ti: j721e-csi2rx: fix list_del corruption If ti_csi2rx_start_dma() fails in ti_csi2rx_dma_callback(), the buffer is marked done with VB2_BUF_STATE_ERROR but is not removed from the DMA queue. This causes the same buffer to be retried in the next iteration, resulting in a double list_del() and eventual list corruption. Fix this by removing the buffer from the queue before calling vb2_buffer_done() on error. This resolves a crash due to list_del corruption: [ 37.811243] j721e-csi2rx 30102000.ticsi2rx: Failed to queue the next buffer for DMA [ 37.832187] slab kmalloc-2k start ffff00000255b000 pointer offset 1064 size 2048 [ 37.839761] list_del corruption. next->prev should be ffff00000255bc28, but was ffff00000255d428. (next=ffff00000255b428) [ 37.850799] ------------[ cut here ]------------ [ 37.855424] kernel BUG at lib/list_debug.c:65! [ 37.859876] Internal error: Oops - BUG: 00000000f2000800 [#1] SMP [ 37.866061] Modules linked in: i2c_dev usb_f_rndis u_ether libcomposite dwc3 udc_core usb_common aes_ce_blk aes_ce_cipher ghash_ce gf128mul sha1_ce cpufreq_dt dwc3_am62 phy_gmii_sel sa2ul [ 37.882830] CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.16.0-rc3+ #28 VOLUNTARY [ 37.890851] Hardware name: Bosch STLA-GSRV2-B0 (DT) [ 37.895737] pstate: 600000c5 (nZCv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 37.902703] pc : __list_del_entry_valid_or_report+0xdc/0x114 [ 37.908390] lr : __list_del_entry_valid_or_report+0xdc/0x114 [ 37.914059] sp : ffff800080003db0 [ 37.917375] x29: ffff800080003db0 x28: 0000000000000007 x27: ffff800080e50000 [ 37.924521] x26: 0000000000000000 x25: ffff0000016abb50 x24: dead000000000122 [ 37.931666] x23: ffff0000016abb78 x22: ffff0000016ab080 x21: ffff800080003de0 [ 37.938810] x20: ffff00000255bc00 x19: ffff00000255b800 x18: 000000000000000a [ 37.945956] x17: 20747562202c3832 x16: 6362353532303030 x15: 0720072007200720 [ 37.953101] x14: 0720072007200720 x13: 0720072007200720 x12: 00000000ffffffea [ 37.960248] x11: ffff800080003b18 x10: 00000000ffffefff x9 : ffff800080f5b568 [ 37.967396] x8 : ffff800080f5b5c0 x7 : 0000000000017fe8 x6 : c0000000ffffefff [ 37.974542] x5 : ffff00000fea6688 x4 : 0000000000000000 x3 : 0000000000000000 [ 37.981686] x2 : 0000000000000000 x1 : ffff800080ef2b40 x0 : 000000000000006d [ 37.988832] Call trace: [ 37.991281] __list_del_entry_valid_or_report+0xdc/0x114 (P) [ 37.996959] ti_csi2rx_dma_callback+0x84/0x1c4 [ 38.001419] udma_vchan_complete+0x1e0/0x344 [ 38.005705] tasklet_action_common+0x118/0x310 [ 38.010163] tasklet_action+0x30/0x3c [ 38.013832] handle_softirqs+0x10c/0x2e0 [ 38.017761] __do_softirq+0x14/0x20 [ 38.021256] ____do_softirq+0x10/0x20 [ 38.024931] call_on_irq_stack+0x24/0x60 [ 38.028873] do_softirq_own_stack+0x1c/0x40 [ 38.033064] __irq_exit_rcu+0x130/0x15c [ 38.036909] irq_exit_rcu+0x10/0x20 [ 38.040403] el1_interrupt+0x38/0x60 [ 38.043987] el1h_64_irq_handler+0x18/0x24 [ 38.048091] el1h_64_irq+0x6c/0x70 [ 38.051501] default_idle_call+0x34/0xe0 (P) [ 38.055783] do_idle+0x1f8/0x250 [ 38.059021] cpu_startup_entry+0x34/0x3c [ 38.062951] rest_init+0xb4/0xc0 [ 38.066186] console_on_rootfs+0x0/0x6c [ 38.070031] __primary_switched+0x88/0x90 [ 38.074059] Code: b00037e0 91378000 f9400462 97e9bf49 (d4210000) [ 38.080168] ---[ end trace 0000000000000000 ]--- [ 38.084795] Kernel panic - not syncing: Oops - BUG: Fatal exception in interrupt [ 38.092197] SMP: stopping secondary CPUs [ 38.096139] Kernel Offset: disabled [ 38.099631] CPU features: 0x0000,00002000,02000801,0400420b [ 38.105202] Memory Limit: none [ 38.108260] ---[ end Kernel panic - not syncing: Oops - BUG: Fatal exception in interrupt ]---Show less