Vulnerabilities > Linux > Linux Kernel > 4.4.95

DATE CVE VULNERABILITY TITLE RISK
2024-10-21 CVE-2024-49867 Use After Free vulnerability in Linux Kernel
In the Linux kernel, the following vulnerability has been resolved: btrfs: wait for fixup workers before stopping cleaner kthread during umount During unmount, at close_ctree(), we have the following steps in this order: 1) Park the cleaner kthread - this doesn't destroy the kthread, it basically halts its execution (wake ups against it work but do nothing); 2) We stop the cleaner kthread - this results in freeing the respective struct task_struct; 3) We call btrfs_stop_all_workers() which waits for any jobs running in all the work queues and then free the work queues. Syzbot reported a case where a fixup worker resulted in a crash when doing a delayed iput on its inode while attempting to wake up the cleaner at btrfs_add_delayed_iput(), because the task_struct of the cleaner kthread was already freed.
local
low complexity
linux CWE-416
5.5
2024-10-21 CVE-2024-49868 NULL Pointer Dereference vulnerability in Linux Kernel
In the Linux kernel, the following vulnerability has been resolved: btrfs: fix a NULL pointer dereference when failed to start a new trasacntion [BUG] Syzbot reported a NULL pointer dereference with the following crash: FAULT_INJECTION: forcing a failure. start_transaction+0x830/0x1670 fs/btrfs/transaction.c:676 prepare_to_relocate+0x31f/0x4c0 fs/btrfs/relocation.c:3642 relocate_block_group+0x169/0xd20 fs/btrfs/relocation.c:3678 ... BTRFS info (device loop0): balance: ended with status: -12 Oops: general protection fault, probably for non-canonical address 0xdffffc00000000cc: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000660-0x0000000000000667] RIP: 0010:btrfs_update_reloc_root+0x362/0xa80 fs/btrfs/relocation.c:926 Call Trace: <TASK> commit_fs_roots+0x2ee/0x720 fs/btrfs/transaction.c:1496 btrfs_commit_transaction+0xfaf/0x3740 fs/btrfs/transaction.c:2430 del_balance_item fs/btrfs/volumes.c:3678 [inline] reset_balance_state+0x25e/0x3c0 fs/btrfs/volumes.c:3742 btrfs_balance+0xead/0x10c0 fs/btrfs/volumes.c:4574 btrfs_ioctl_balance+0x493/0x7c0 fs/btrfs/ioctl.c:3673 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f [CAUSE] The allocation failure happens at the start_transaction() inside prepare_to_relocate(), and during the error handling we call unset_reloc_control(), which makes fs_info->balance_ctl to be NULL. Then we continue the error path cleanup in btrfs_balance() by calling reset_balance_state() which will call del_balance_item() to fully delete the balance item in the root tree. However during the small window between set_reloc_contrl() and unset_reloc_control(), we can have a subvolume tree update and created a reloc_root for that subvolume. Then we go into the final btrfs_commit_transaction() of del_balance_item(), and into btrfs_update_reloc_root() inside commit_fs_roots(). That function checks if fs_info->reloc_ctl is in the merge_reloc_tree stage, but since fs_info->reloc_ctl is NULL, it results a NULL pointer dereference. [FIX] Just add extra check on fs_info->reloc_ctl inside btrfs_update_reloc_root(), before checking fs_info->reloc_ctl->merge_reloc_tree. That DEAD_RELOC_TREE handling is to prevent further modification to the reloc tree during merge stage, but since there is no reloc_ctl at all, we do not need to bother that.
local
low complexity
linux CWE-476
5.5
2024-10-21 CVE-2024-49875 Improper Validation of Integrity Check Value vulnerability in Linux Kernel
In the Linux kernel, the following vulnerability has been resolved: nfsd: map the EBADMSG to nfserr_io to avoid warning Ext4 will throw -EBADMSG through ext4_readdir when a checksum error occurs, resulting in the following WARNING. Fix it by mapping EBADMSG to nfserr_io. nfsd_buffered_readdir iterate_dir // -EBADMSG -74 ext4_readdir // .iterate_shared ext4_dx_readdir ext4_htree_fill_tree htree_dirblock_to_tree ext4_read_dirblock __ext4_read_dirblock ext4_dirblock_csum_verify warn_no_space_for_csum __warn_no_space_for_csum return ERR_PTR(-EFSBADCRC) // -EBADMSG -74 nfserrno // WARNING [ 161.115610] ------------[ cut here ]------------ [ 161.116465] nfsd: non-standard errno: -74 [ 161.117315] WARNING: CPU: 1 PID: 780 at fs/nfsd/nfsproc.c:878 nfserrno+0x9d/0xd0 [ 161.118596] Modules linked in: [ 161.119243] CPU: 1 PID: 780 Comm: nfsd Not tainted 5.10.0-00014-g79679361fd5d #138 [ 161.120684] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qe mu.org 04/01/2014 [ 161.123601] RIP: 0010:nfserrno+0x9d/0xd0 [ 161.124676] Code: 0f 87 da 30 dd 00 83 e3 01 b8 00 00 00 05 75 d7 44 89 ee 48 c7 c7 c0 57 24 98 89 44 24 04 c6 05 ce 2b 61 03 01 e8 99 20 d8 00 <0f> 0b 8b 44 24 04 eb b5 4c 89 e6 48 c7 c7 a0 6d a4 99 e8 cc 15 33 [ 161.127797] RSP: 0018:ffffc90000e2f9c0 EFLAGS: 00010286 [ 161.128794] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 161.130089] RDX: 1ffff1103ee16f6d RSI: 0000000000000008 RDI: fffff520001c5f2a [ 161.131379] RBP: 0000000000000022 R08: 0000000000000001 R09: ffff8881f70c1827 [ 161.132664] R10: ffffed103ee18304 R11: 0000000000000001 R12: 0000000000000021 [ 161.133949] R13: 00000000ffffffb6 R14: ffff8881317c0000 R15: ffffc90000e2fbd8 [ 161.135244] FS: 0000000000000000(0000) GS:ffff8881f7080000(0000) knlGS:0000000000000000 [ 161.136695] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 161.137761] CR2: 00007fcaad70b348 CR3: 0000000144256006 CR4: 0000000000770ee0 [ 161.139041] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 161.140291] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 161.141519] PKRU: 55555554 [ 161.142076] Call Trace: [ 161.142575] ? __warn+0x9b/0x140 [ 161.143229] ? nfserrno+0x9d/0xd0 [ 161.143872] ? report_bug+0x125/0x150 [ 161.144595] ? handle_bug+0x41/0x90 [ 161.145284] ? exc_invalid_op+0x14/0x70 [ 161.146009] ? asm_exc_invalid_op+0x12/0x20 [ 161.146816] ? nfserrno+0x9d/0xd0 [ 161.147487] nfsd_buffered_readdir+0x28b/0x2b0 [ 161.148333] ? nfsd4_encode_dirent_fattr+0x380/0x380 [ 161.149258] ? nfsd_buffered_filldir+0xf0/0xf0 [ 161.150093] ? wait_for_concurrent_writes+0x170/0x170 [ 161.151004] ? generic_file_llseek_size+0x48/0x160 [ 161.151895] nfsd_readdir+0x132/0x190 [ 161.152606] ? nfsd4_encode_dirent_fattr+0x380/0x380 [ 161.153516] ? nfsd_unlink+0x380/0x380 [ 161.154256] ? override_creds+0x45/0x60 [ 161.155006] nfsd4_encode_readdir+0x21a/0x3d0 [ 161.155850] ? nfsd4_encode_readlink+0x210/0x210 [ 161.156731] ? write_bytes_to_xdr_buf+0x97/0xe0 [ 161.157598] ? __write_bytes_to_xdr_buf+0xd0/0xd0 [ 161.158494] ? lock_downgrade+0x90/0x90 [ 161.159232] ? nfs4svc_decode_voidarg+0x10/0x10 [ 161.160092] nfsd4_encode_operation+0x15a/0x440 [ 161.160959] nfsd4_proc_compound+0x718/0xe90 [ 161.161818] nfsd_dispatch+0x18e/0x2c0 [ 161.162586] svc_process_common+0x786/0xc50 [ 161.163403] ? nfsd_svc+0x380/0x380 [ 161.164137] ? svc_printk+0x160/0x160 [ 161.164846] ? svc_xprt_do_enqueue.part.0+0x365/0x380 [ 161.165808] ? nfsd_svc+0x380/0x380 [ 161.166523] ? rcu_is_watching+0x23/0x40 [ 161.167309] svc_process+0x1a5/0x200 [ 161.168019] nfsd+0x1f5/0x380 [ 161.168663] ? nfsd_shutdown_threads+0x260/0x260 [ 161.169554] kthread+0x1c4/0x210 [ 161.170224] ? kthread_insert_work_sanity_check+0x80/0x80 [ 161.171246] ret_from_fork+0x1f/0x30
local
low complexity
linux CWE-354
5.5
2024-10-21 CVE-2024-49881 NULL Pointer Dereference vulnerability in Linux Kernel
In the Linux kernel, the following vulnerability has been resolved: ext4: update orig_path in ext4_find_extent() In ext4_find_extent(), if the path is not big enough, we free it and set *orig_path to NULL.
local
low complexity
linux CWE-476
5.5
2024-10-21 CVE-2024-49882 Double Free vulnerability in Linux Kernel
In the Linux kernel, the following vulnerability has been resolved: ext4: fix double brelse() the buffer of the extents path In ext4_ext_try_to_merge_up(), set path[1].p_bh to NULL after it has been released, otherwise it may be released twice.
local
low complexity
linux CWE-415
7.8
2024-10-21 CVE-2024-49883 Use After Free vulnerability in Linux Kernel
In the Linux kernel, the following vulnerability has been resolved: ext4: aovid use-after-free in ext4_ext_insert_extent() As Ojaswin mentioned in Link, in ext4_ext_insert_extent(), if the path is reallocated in ext4_ext_create_new_leaf(), we'll use the stale path and cause UAF.
local
low complexity
linux CWE-416
7.8
2024-10-21 CVE-2024-49884 Use After Free vulnerability in Linux Kernel
In the Linux kernel, the following vulnerability has been resolved: ext4: fix slab-use-after-free in ext4_split_extent_at() We hit the following use-after-free: ================================================================== BUG: KASAN: slab-use-after-free in ext4_split_extent_at+0xba8/0xcc0 Read of size 2 at addr ffff88810548ed08 by task kworker/u20:0/40 CPU: 0 PID: 40 Comm: kworker/u20:0 Not tainted 6.9.0-dirty #724 Call Trace: <TASK> kasan_report+0x93/0xc0 ext4_split_extent_at+0xba8/0xcc0 ext4_split_extent.isra.0+0x18f/0x500 ext4_split_convert_extents+0x275/0x750 ext4_ext_handle_unwritten_extents+0x73e/0x1580 ext4_ext_map_blocks+0xe20/0x2dc0 ext4_map_blocks+0x724/0x1700 ext4_do_writepages+0x12d6/0x2a70 [...] Allocated by task 40: __kmalloc_noprof+0x1ac/0x480 ext4_find_extent+0xf3b/0x1e70 ext4_ext_map_blocks+0x188/0x2dc0 ext4_map_blocks+0x724/0x1700 ext4_do_writepages+0x12d6/0x2a70 [...] Freed by task 40: kfree+0xf1/0x2b0 ext4_find_extent+0xa71/0x1e70 ext4_ext_insert_extent+0xa22/0x3260 ext4_split_extent_at+0x3ef/0xcc0 ext4_split_extent.isra.0+0x18f/0x500 ext4_split_convert_extents+0x275/0x750 ext4_ext_handle_unwritten_extents+0x73e/0x1580 ext4_ext_map_blocks+0xe20/0x2dc0 ext4_map_blocks+0x724/0x1700 ext4_do_writepages+0x12d6/0x2a70 [...] ================================================================== The flow of issue triggering is as follows: ext4_split_extent_at path = *ppath ext4_ext_insert_extent(ppath) ext4_ext_create_new_leaf(ppath) ext4_find_extent(orig_path) path = *orig_path read_extent_tree_block // return -ENOMEM or -EIO ext4_free_ext_path(path) kfree(path) *orig_path = NULL a.
local
low complexity
linux CWE-416
7.8
2024-10-21 CVE-2024-49888 Integer Overflow or Wraparound vulnerability in Linux Kernel
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix a sdiv overflow issue Zac Ecob reported a problem where a bpf program may cause kernel crash due to the following error: Oops: divide error: 0000 [#1] PREEMPT SMP KASAN PTI The failure is due to the below signed divide: LLONG_MIN/-1 where LLONG_MIN equals to -9,223,372,036,854,775,808. LLONG_MIN/-1 is supposed to give a positive number 9,223,372,036,854,775,808, but it is impossible since for 64-bit system, the maximum positive number is 9,223,372,036,854,775,807.
local
low complexity
linux CWE-190
5.5
2024-10-21 CVE-2024-49889 Use After Free vulnerability in Linux Kernel
In the Linux kernel, the following vulnerability has been resolved: ext4: avoid use-after-free in ext4_ext_show_leaf() In ext4_find_extent(), path may be freed by error or be reallocated, so using a previously saved *ppath may have been freed and thus may trigger use-after-free, as follows: ext4_split_extent path = *ppath; ext4_split_extent_at(ppath) path = ext4_find_extent(ppath) ext4_split_extent_at(ppath) // ext4_find_extent fails to free path // but zeroout succeeds ext4_ext_show_leaf(inode, path) eh = path[depth].p_hdr // path use-after-free !!! Similar to ext4_split_extent_at(), we use *ppath directly as an input to ext4_ext_show_leaf().
local
low complexity
linux CWE-416
7.8
2024-10-21 CVE-2024-49890 NULL Pointer Dereference vulnerability in Linux Kernel
In the Linux kernel, the following vulnerability has been resolved: drm/amd/pm: ensure the fw_info is not null before using it This resolves the dereference null return value warning reported by Coverity.
local
low complexity
linux CWE-476
5.5