Vulnerabilities
Vulnerable Software
Linux:  >> Linux Kernel  >> 2.6.20.9  Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved: scsi: qla2xxx: Fix command flush on cable pull System crash due to command failed to flush back to SCSI layer. BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 PGD 0 P4D 0 Oops: 0000 [#1] SMP NOPTI CPU: 27 PID: 793455 Comm: kworker/u130:6 Kdump: loaded Tainted: G OE --------- - - 4.18.0-372.9.1.el8.x86_64 #1 Hardware name: HPE ProLiant DL360 Gen10/ProLiant DL360 Gen10, BIOS U32 09/03/2021 Workqueue: nvme-wq nvme_fc_connect_ctrl_work [nvme_fc] RIP: 0010:__wake_up_common+0x4c/0x190 Code: 24 10 4d 85 c9 74 0a 41 f6 01 04 0f 85 9d 00 00 00 48 8b 43 08 48 83 c3 08 4c 8d 48 e8 49 8d 41 18 48 39 c3 0f 84 f0 00 00 00 <49> 8b 41 18 89 54 24 08 31 ed 4c 8d 70 e8 45 8b 29 41 f6 c5 04 75 RSP: 0018:ffff95f3e0cb7cd0 EFLAGS: 00010086 RAX: 0000000000000000 RBX: ffff8b08d3b26328 RCX: 0000000000000000 RDX: 0000000000000001 RSI: 0000000000000003 RDI: ffff8b08d3b26320 RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffffffffffe8 R10: 0000000000000000 R11: ffff95f3e0cb7a60 R12: ffff95f3e0cb7d20 R13: 0000000000000003 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8b2fdf6c0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000002f1e410002 CR4: 00000000007706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: __wake_up_common_lock+0x7c/0xc0 qla_nvme_ls_req+0x355/0x4c0 [qla2xxx] qla2xxx [0000:12:00.1]-f084:3: qlt_free_session_done: se_sess 0000000000000000 / sess ffff8ae1407ca000 from port 21:32:00:02:ac:07:ee:b8 loop_id 0x02 s_id 01:02:00 logout 1 keep 0 els_logo 0 ? __nvme_fc_send_ls_req+0x260/0x380 [nvme_fc] qla2xxx [0000:12:00.1]-207d:3: FCPort 21:32:00:02:ac:07:ee:b8 state transitioned from ONLINE to LOST - portid=010200. ? nvme_fc_send_ls_req.constprop.42+0x1a/0x45 [nvme_fc] qla2xxx [0000:12:00.1]-2109:3: qla2x00_schedule_rport_del 21320002ac07eeb8. rport ffff8ae598122000 roles 1 ? nvme_fc_connect_ctrl_work.cold.63+0x1e3/0xa7d [nvme_fc] qla2xxx [0000:12:00.1]-f084:3: qlt_free_session_done: se_sess 0000000000000000 / sess ffff8ae14801e000 from port 21:32:01:02:ad:f7:ee:b8 loop_id 0x04 s_id 01:02:01 logout 1 keep 0 els_logo 0 ? __switch_to+0x10c/0x450 ? process_one_work+0x1a7/0x360 qla2xxx [0000:12:00.1]-207d:3: FCPort 21:32:01:02:ad:f7:ee:b8 state transitioned from ONLINE to LOST - portid=010201. ? worker_thread+0x1ce/0x390 ? create_worker+0x1a0/0x1a0 qla2xxx [0000:12:00.1]-2109:3: qla2x00_schedule_rport_del 21320102adf7eeb8. rport ffff8ae3b2312800 roles 70 ? kthread+0x10a/0x120 qla2xxx [0000:12:00.1]-2112:3: qla_nvme_unregister_remote_port: unregister remoteport on ffff8ae14801e000 21320102adf7eeb8 ? set_kthread_struct+0x40/0x40 qla2xxx [0000:12:00.1]-2110:3: remoteport_delete of ffff8ae14801e000 21320102adf7eeb8 completed. ? ret_from_fork+0x1f/0x40 qla2xxx [0000:12:00.1]-f086:3: qlt_free_session_done: waiting for sess ffff8ae14801e000 logout The system was under memory stress where driver was not able to allocate an SRB to carry out error recovery of cable pull. The failure to flush causes upper layer to start modifying scsi_cmnd. When the system frees up some memory, the subsequent cable pull trigger another command flush. At this point the driver access a null pointer when attempting to DMA unmap the SGL. Add a check to make sure commands are flush back on session tear down to prevent the null pointer access.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-05-01
In the Linux kernel, the following vulnerability has been resolved: ext4: fix bug in extents parsing when eh_entries == 0 and eh_depth > 0 When walking through an inode extents, the ext4_ext_binsearch_idx() function assumes that the extent header has been previously validated. However, there are no checks that verify that the number of entries (eh->eh_entries) is non-zero when depth is > 0. And this will lead to problems because the EXT_FIRST_INDEX() and EXT_LAST_INDEX() will return garbage and result in this: [ 135.245946] ------------[ cut here ]------------ [ 135.247579] kernel BUG at fs/ext4/extents.c:2258! [ 135.249045] invalid opcode: 0000 [#1] PREEMPT SMP [ 135.250320] CPU: 2 PID: 238 Comm: tmp118 Not tainted 5.19.0-rc8+ #4 [ 135.252067] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b-rebuilt.opensuse.org 04/01/2014 [ 135.255065] RIP: 0010:ext4_ext_map_blocks+0xc20/0xcb0 [ 135.256475] Code: [ 135.261433] RSP: 0018:ffffc900005939f8 EFLAGS: 00010246 [ 135.262847] RAX: 0000000000000024 RBX: ffffc90000593b70 RCX: 0000000000000023 [ 135.264765] RDX: ffff8880038e5f10 RSI: 0000000000000003 RDI: ffff8880046e922c [ 135.266670] RBP: ffff8880046e9348 R08: 0000000000000001 R09: ffff888002ca580c [ 135.268576] R10: 0000000000002602 R11: 0000000000000000 R12: 0000000000000024 [ 135.270477] R13: 0000000000000000 R14: 0000000000000024 R15: 0000000000000000 [ 135.272394] FS: 00007fdabdc56740(0000) GS:ffff88807dd00000(0000) knlGS:0000000000000000 [ 135.274510] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 135.276075] CR2: 00007ffc26bd4f00 CR3: 0000000006261004 CR4: 0000000000170ea0 [ 135.277952] Call Trace: [ 135.278635] <TASK> [ 135.279247] ? preempt_count_add+0x6d/0xa0 [ 135.280358] ? percpu_counter_add_batch+0x55/0xb0 [ 135.281612] ? _raw_read_unlock+0x18/0x30 [ 135.282704] ext4_map_blocks+0x294/0x5a0 [ 135.283745] ? xa_load+0x6f/0xa0 [ 135.284562] ext4_mpage_readpages+0x3d6/0x770 [ 135.285646] read_pages+0x67/0x1d0 [ 135.286492] ? folio_add_lru+0x51/0x80 [ 135.287441] page_cache_ra_unbounded+0x124/0x170 [ 135.288510] filemap_get_pages+0x23d/0x5a0 [ 135.289457] ? path_openat+0xa72/0xdd0 [ 135.290332] filemap_read+0xbf/0x300 [ 135.291158] ? _raw_spin_lock_irqsave+0x17/0x40 [ 135.292192] new_sync_read+0x103/0x170 [ 135.293014] vfs_read+0x15d/0x180 [ 135.293745] ksys_read+0xa1/0xe0 [ 135.294461] do_syscall_64+0x3c/0x80 [ 135.295284] entry_SYSCALL_64_after_hwframe+0x46/0xb0 This patch simply adds an extra check in __ext4_ext_check(), verifying that eh_entries is not 0 when eh_depth is > 0.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-04-28
In the Linux kernel, the following vulnerability has been resolved: drm/gma500: Fix WARN_ON(lock->magic != lock) error psb_gem_unpin() calls dma_resv_lock() but the underlying ww_mutex gets destroyed by drm_gem_object_release() move the drm_gem_object_release() call in psb_gem_free_object() to after the unpin to fix the below warning: [ 79.693962] ------------[ cut here ]------------ [ 79.693992] DEBUG_LOCKS_WARN_ON(lock->magic != lock) [ 79.694015] WARNING: CPU: 0 PID: 240 at kernel/locking/mutex.c:582 __ww_mutex_lock.constprop.0+0x569/0xfb0 [ 79.694052] Modules linked in: rfcomm snd_seq_dummy snd_hrtimer qrtr bnep ath9k ath9k_common ath9k_hw snd_hda_codec_realtek snd_hda_codec_generic ledtrig_audio snd_hda_codec_hdmi snd_hda_intel ath3k snd_intel_dspcfg mac80211 snd_intel_sdw_acpi btusb snd_hda_codec btrtl btbcm btintel btmtk bluetooth at24 snd_hda_core snd_hwdep uvcvideo snd_seq libarc4 videobuf2_vmalloc ath videobuf2_memops videobuf2_v4l2 videobuf2_common snd_seq_device videodev acer_wmi intel_powerclamp coretemp mc snd_pcm joydev sparse_keymap ecdh_generic pcspkr wmi_bmof cfg80211 i2c_i801 i2c_smbus snd_timer snd r8169 rfkill lpc_ich soundcore acpi_cpufreq zram rtsx_pci_sdmmc mmc_core serio_raw rtsx_pci gma500_gfx(E) video wmi ip6_tables ip_tables i2c_dev fuse [ 79.694436] CPU: 0 PID: 240 Comm: plymouthd Tainted: G W E 6.0.0-rc3+ #490 [ 79.694457] Hardware name: Packard Bell dot s/SJE01_CT, BIOS V1.10 07/23/2013 [ 79.694469] RIP: 0010:__ww_mutex_lock.constprop.0+0x569/0xfb0 [ 79.694496] Code: ff 85 c0 0f 84 15 fb ff ff 8b 05 ca 3c 11 01 85 c0 0f 85 07 fb ff ff 48 c7 c6 30 cb 84 aa 48 c7 c7 a3 e1 82 aa e8 ac 29 f8 ff <0f> 0b e9 ed fa ff ff e8 5b 83 8a ff 85 c0 74 10 44 8b 0d 98 3c 11 [ 79.694513] RSP: 0018:ffffad1dc048bbe0 EFLAGS: 00010282 [ 79.694623] RAX: 0000000000000028 RBX: 0000000000000000 RCX: 0000000000000000 [ 79.694636] RDX: 0000000000000001 RSI: ffffffffaa8b0ffc RDI: 00000000ffffffff [ 79.694650] RBP: ffffad1dc048bc80 R08: 0000000000000000 R09: ffffad1dc048ba90 [ 79.694662] R10: 0000000000000003 R11: ffffffffaad62fe8 R12: ffff9ff302103138 [ 79.694675] R13: ffff9ff306ec8000 R14: ffff9ff307779078 R15: ffff9ff3014c0270 [ 79.694690] FS: 00007ff1cccf1740(0000) GS:ffff9ff3bc200000(0000) knlGS:0000000000000000 [ 79.694705] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 79.694719] CR2: 0000559ecbcb4420 CR3: 0000000013210000 CR4: 00000000000006f0 [ 79.694734] Call Trace: [ 79.694749] <TASK> [ 79.694761] ? __schedule+0x47f/0x1670 [ 79.694796] ? psb_gem_unpin+0x27/0x1a0 [gma500_gfx] [ 79.694830] ? lock_is_held_type+0xe3/0x140 [ 79.694864] ? ww_mutex_lock+0x38/0xa0 [ 79.694885] ? __cond_resched+0x1c/0x30 [ 79.694902] ww_mutex_lock+0x38/0xa0 [ 79.694925] psb_gem_unpin+0x27/0x1a0 [gma500_gfx] [ 79.694964] psb_gem_unpin+0x199/0x1a0 [gma500_gfx] [ 79.694996] drm_gem_object_release_handle+0x50/0x60 [ 79.695020] ? drm_gem_object_handle_put_unlocked+0xf0/0xf0 [ 79.695042] idr_for_each+0x4b/0xb0 [ 79.695066] ? _raw_spin_unlock_irqrestore+0x30/0x60 [ 79.695095] drm_gem_release+0x1c/0x30 [ 79.695118] drm_file_free.part.0+0x1ea/0x260 [ 79.695150] drm_release+0x6a/0x120 [ 79.695175] __fput+0x9f/0x260 [ 79.695203] task_work_run+0x59/0xa0 [ 79.695227] do_exit+0x387/0xbe0 [ 79.695250] ? seqcount_lockdep_reader_access.constprop.0+0x82/0x90 [ 79.695275] ? lockdep_hardirqs_on+0x7d/0x100 [ 79.695304] do_group_exit+0x33/0xb0 [ 79.695331] __x64_sys_exit_group+0x14/0x20 [ 79.695353] do_syscall_64+0x58/0x80 [ 79.695376] ? up_read+0x17/0x20 [ 79.695401] ? lock_is_held_type+0xe3/0x140 [ 79.695429] ? asm_exc_page_fault+0x22/0x30 [ 79.695450] ? lockdep_hardirqs_on+0x7d/0x100 [ 79.695473] entry_SYSCALL_64_after_hwframe+0x63/0xcd [ 79.695493] RIP: 0033:0x7ff1ccefe3f1 [ 79.695516] Code: Unable to access opcode bytes at RIP 0x7ff1ccefe3c7. [ 79.695607] RSP: 002b:00007ffed4413378 EFLAGS: ---truncated---
CVSS Score
5.5
EPSS Score
0.0
Published
2024-04-28
In the Linux kernel, the following vulnerability has been resolved: drm/gma500: Fix BUG: sleeping function called from invalid context errors gma_crtc_page_flip() was holding the event_lock spinlock while calling crtc_funcs->mode_set_base() which takes ww_mutex. The only reason to hold event_lock is to clear gma_crtc->page_flip_event on mode_set_base() errors. Instead unlock it after setting gma_crtc->page_flip_event and on errors re-take the lock and clear gma_crtc->page_flip_event it it is still set. This fixes the following WARN/stacktrace: [ 512.122953] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:870 [ 512.123004] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 1253, name: gnome-shell [ 512.123031] preempt_count: 1, expected: 0 [ 512.123048] RCU nest depth: 0, expected: 0 [ 512.123066] INFO: lockdep is turned off. [ 512.123080] irq event stamp: 0 [ 512.123094] hardirqs last enabled at (0): [<0000000000000000>] 0x0 [ 512.123134] hardirqs last disabled at (0): [<ffffffff8d0ec28c>] copy_process+0x9fc/0x1de0 [ 512.123176] softirqs last enabled at (0): [<ffffffff8d0ec28c>] copy_process+0x9fc/0x1de0 [ 512.123207] softirqs last disabled at (0): [<0000000000000000>] 0x0 [ 512.123233] Preemption disabled at: [ 512.123241] [<0000000000000000>] 0x0 [ 512.123275] CPU: 3 PID: 1253 Comm: gnome-shell Tainted: G W 5.19.0+ #1 [ 512.123304] Hardware name: Packard Bell dot s/SJE01_CT, BIOS V1.10 07/23/2013 [ 512.123323] Call Trace: [ 512.123346] <TASK> [ 512.123370] dump_stack_lvl+0x5b/0x77 [ 512.123412] __might_resched.cold+0xff/0x13a [ 512.123458] ww_mutex_lock+0x1e/0xa0 [ 512.123495] psb_gem_pin+0x2c/0x150 [gma500_gfx] [ 512.123601] gma_pipe_set_base+0x76/0x240 [gma500_gfx] [ 512.123708] gma_crtc_page_flip+0x95/0x130 [gma500_gfx] [ 512.123808] drm_mode_page_flip_ioctl+0x57d/0x5d0 [ 512.123897] ? drm_mode_cursor2_ioctl+0x10/0x10 [ 512.123936] drm_ioctl_kernel+0xa1/0x150 [ 512.123984] drm_ioctl+0x21f/0x420 [ 512.124025] ? drm_mode_cursor2_ioctl+0x10/0x10 [ 512.124070] ? rcu_read_lock_bh_held+0xb/0x60 [ 512.124104] ? lock_release+0x1ef/0x2d0 [ 512.124161] __x64_sys_ioctl+0x8d/0xd0 [ 512.124203] do_syscall_64+0x58/0x80 [ 512.124239] ? do_syscall_64+0x67/0x80 [ 512.124267] ? trace_hardirqs_on_prepare+0x55/0xe0 [ 512.124300] ? do_syscall_64+0x67/0x80 [ 512.124340] ? rcu_read_lock_sched_held+0x10/0x80 [ 512.124377] entry_SYSCALL_64_after_hwframe+0x63/0xcd [ 512.124411] RIP: 0033:0x7fcc4a70740f [ 512.124442] Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 18 48 8b 44 24 18 64 48 2b 04 25 28 00 00 [ 512.124470] RSP: 002b:00007ffda73f5390 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 512.124503] RAX: ffffffffffffffda RBX: 000055cc9e474500 RCX: 00007fcc4a70740f [ 512.124524] RDX: 00007ffda73f5420 RSI: 00000000c01864b0 RDI: 0000000000000009 [ 512.124544] RBP: 00007ffda73f5420 R08: 000055cc9c0b0cb0 R09: 0000000000000034 [ 512.124564] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000c01864b0 [ 512.124584] R13: 0000000000000009 R14: 000055cc9df484d0 R15: 000055cc9af5d0c0 [ 512.124647] </TASK>
CVSS Score
5.3
EPSS Score
0.0
Published
2024-04-28
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix potential UAF in cifs_debug_files_proc_show() Skip sessions that are being teared down (status == SES_EXITING) to avoid UAF.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-04-28
In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: Reset IH OVERFLOW_CLEAR bit Allows us to detect subsequent IH ring buffer overflows as well.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-04-17
In the Linux kernel, the following vulnerability has been resolved: netfilter: ipset: fix performance regression in swap operation The patch "netfilter: ipset: fix race condition between swap/destroy and kernel side add/del/test", commit 28628fa9 fixes a race condition. But the synchronize_rcu() added to the swap function unnecessarily slows it down: it can safely be moved to destroy and use call_rcu() instead. Eric Dumazet pointed out that simply calling the destroy functions as rcu callback does not work: sets with timeout use garbage collectors which need cancelling at destroy which can wait. Therefore the destroy functions are split into two: cancelling garbage collectors safely at executing the command received by netlink and moving the remaining part only into the rcu callback.
CVSS Score
4.7
EPSS Score
0.0
Published
2024-04-17
In the Linux kernel, the following vulnerability has been resolved: perf: RISCV: Fix panic on pmu overflow handler (1 << idx) of int is not desired when setting bits in unsigned long overflowed_ctrs, use BIT() instead. This panic happens when running 'perf record -e branches' on sophgo sg2042. [ 273.311852] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000098 [ 273.320851] Oops [#1] [ 273.323179] Modules linked in: [ 273.326303] CPU: 0 PID: 1475 Comm: perf Not tainted 6.6.0-rc3+ #9 [ 273.332521] Hardware name: Sophgo Mango (DT) [ 273.336878] epc : riscv_pmu_ctr_get_width_mask+0x8/0x62 [ 273.342291] ra : pmu_sbi_ovf_handler+0x2e0/0x34e [ 273.347091] epc : ffffffff80aecd98 ra : ffffffff80aee056 sp : fffffff6e36928b0 [ 273.354454] gp : ffffffff821f82d0 tp : ffffffd90c353200 t0 : 0000002ade4f9978 [ 273.361815] t1 : 0000000000504d55 t2 : ffffffff8016cd8c s0 : fffffff6e3692a70 [ 273.369180] s1 : 0000000000000020 a0 : 0000000000000000 a1 : 00001a8e81800000 [ 273.376540] a2 : 0000003c00070198 a3 : 0000003c00db75a4 a4 : 0000000000000015 [ 273.383901] a5 : ffffffd7ff8804b0 a6 : 0000000000000015 a7 : 000000000000002a [ 273.391327] s2 : 000000000000ffff s3 : 0000000000000000 s4 : ffffffd7ff8803b0 [ 273.398773] s5 : 0000000000504d55 s6 : ffffffd905069800 s7 : ffffffff821fe210 [ 273.406139] s8 : 000000007fffffff s9 : ffffffd7ff8803b0 s10: ffffffd903f29098 [ 273.413660] s11: 0000000080000000 t3 : 0000000000000003 t4 : ffffffff8017a0ca [ 273.421022] t5 : ffffffff8023cfc2 t6 : ffffffd9040780e8 [ 273.426437] status: 0000000200000100 badaddr: 0000000000000098 cause: 000000000000000d [ 273.434512] [<ffffffff80aecd98>] riscv_pmu_ctr_get_width_mask+0x8/0x62 [ 273.441169] [<ffffffff80076bd8>] handle_percpu_devid_irq+0x98/0x1ee [ 273.447562] [<ffffffff80071158>] generic_handle_domain_irq+0x28/0x36 [ 273.454151] [<ffffffff8047a99a>] riscv_intc_irq+0x36/0x4e [ 273.459659] [<ffffffff80c944de>] handle_riscv_irq+0x4a/0x74 [ 273.465442] [<ffffffff80c94c48>] do_irq+0x62/0x92 [ 273.470360] Code: 0420 60a2 6402 5529 0141 8082 0013 0000 0013 0000 (6d5c) b783 [ 273.477921] ---[ end trace 0000000000000000 ]--- [ 273.482630] Kernel panic - not syncing: Fatal exception in interrupt
CVSS Score
5.5
EPSS Score
0.0
Published
2024-04-17
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: rfcomm: Fix null-ptr-deref in rfcomm_check_security During our fuzz testing of the connection and disconnection process at the RFCOMM layer, we discovered this bug. By comparing the packets from a normal connection and disconnection process with the testcase that triggered a KASAN report. We analyzed the cause of this bug as follows: 1. In the packets captured during a normal connection, the host sends a `Read Encryption Key Size` type of `HCI_CMD` packet (Command Opcode: 0x1408) to the controller to inquire the length of encryption key.After receiving this packet, the controller immediately replies with a Command Completepacket (Event Code: 0x0e) to return the Encryption Key Size. 2. In our fuzz test case, the timing of the controller's response to this packet was delayed to an unexpected point: after the RFCOMM and L2CAP layers had disconnected but before the HCI layer had disconnected. 3. After receiving the Encryption Key Size Response at the time described in point 2, the host still called the rfcomm_check_security function. However, by this time `struct l2cap_conn *conn = l2cap_pi(sk)->chan->conn;` had already been released, and when the function executed `return hci_conn_security(conn->hcon, d->sec_level, auth_type, d->out);`, specifically when accessing `conn->hcon`, a null-ptr-deref error occurred. To fix this bug, check if `sk->sk_state` is BT_CLOSED before calling rfcomm_recv_frame in rfcomm_process_rx.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-04-17
In the Linux kernel, the following vulnerability has been resolved: x86/mm: Disallow vsyscall page read for copy_from_kernel_nofault() When trying to use copy_from_kernel_nofault() to read vsyscall page through a bpf program, the following oops was reported: BUG: unable to handle page fault for address: ffffffffff600000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 3231067 P4D 3231067 PUD 3233067 PMD 3235067 PTE 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 1 PID: 20390 Comm: test_progs ...... 6.7.0+ #58 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ...... RIP: 0010:copy_from_kernel_nofault+0x6f/0x110 ...... Call Trace: <TASK> ? copy_from_kernel_nofault+0x6f/0x110 bpf_probe_read_kernel+0x1d/0x50 bpf_prog_2061065e56845f08_do_probe_read+0x51/0x8d trace_call_bpf+0xc5/0x1c0 perf_call_bpf_enter.isra.0+0x69/0xb0 perf_syscall_enter+0x13e/0x200 syscall_trace_enter+0x188/0x1c0 do_syscall_64+0xb5/0xe0 entry_SYSCALL_64_after_hwframe+0x6e/0x76 </TASK> ...... ---[ end trace 0000000000000000 ]--- The oops is triggered when: 1) A bpf program uses bpf_probe_read_kernel() to read from the vsyscall page and invokes copy_from_kernel_nofault() which in turn calls __get_user_asm(). 2) Because the vsyscall page address is not readable from kernel space, a page fault exception is triggered accordingly. 3) handle_page_fault() considers the vsyscall page address as a user space address instead of a kernel space address. This results in the fix-up setup by bpf not being applied and a page_fault_oops() is invoked due to SMAP. Considering handle_page_fault() has already considered the vsyscall page address as a userspace address, fix the problem by disallowing vsyscall page read for copy_from_kernel_nofault().
CVSS Score
5.5
EPSS Score
0.0
Published
2024-04-17


Contact Us

Shodan ® - All rights reserved