# CVE-2024-50225: btrfs: fix error propagation of split bios CVE-2024-50225 is fixed in 26 products on 1 platform, first by DEBIAN-CVE-2024-50225, released November 9, 2024. It is not reported as exploited. Patch Radar priority: Routine. - Web page: https://patchblox.com/security/cve/CVE-2024-50225 - Priority: Routine - CVSS: 5.5 (medium) - EPSS: 0.0021 - CISA KEV: not listed - Exploited (vendor report): no - Publicly disclosed: no - Published: Nov 9, 2024 - Weakness: NULL Pointer Dereference - Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-50225 ## Description In the Linux kernel, the following vulnerability has been resolved: btrfs: fix error propagation of split bios The purpose of btrfs_bbio_propagate_error() shall be propagating an error of split bio to its original btrfs_bio, and tell the error to the upper layer. However, it's not working well on some cases. * Case 1. Immediate (or quick) end_bio with an error When btrfs sends btrfs_bio to mirrored devices, btrfs calls btrfs_bio_end_io() when all the mirroring bios are completed. If that btrfs_bio was split, it is from btrfs_clone_bioset and its end_io function is btrfs_orig_write_end_io. For this case, btrfs_bbio_propagate_error() accesses the orig_bbio's bio context to increase the error count. That works well in most cases. However, if the end_io is called enough fast, orig_bbio's (remaining part after split) bio context may not be properly set at that time. Since the bio context is set when the orig_bbio (the last btrfs_bio) is sent to devices, that might be too late for earlier split btrfs_bio's completion. That will result in NULL pointer dereference. That bug is easily reproducible by running btrfs/146 on zoned devices [1] and it shows the following trace. [1] You need raid-stripe-tree feature as it create "-d raid0 -m raid1" FS. BUG: kernel NULL pointer dereference, address: 0000000000000020 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: Oops: 0000 [#1] PREEMPT SMP PTI CPU: 1 UID: 0 PID: 13 Comm: kworker/u32:1 Not tainted 6.11.0-rc7-BTRFS-ZNS+ #474 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 Workqueue: writeback wb_workfn (flush-btrfs-5) RIP: 0010:btrfs_bio_end_io+0xae/0xc0 [btrfs] BTRFS error (device dm-0): bdev /dev/mapper/error-test errs: wr 2, rd 0, flush 0, corrupt 0, gen 0 RSP: 0018:ffffc9000006f248 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff888005a7f080 RCX: ffffc9000006f1dc RDX: 0000000000000000 RSI: 000000000000000a RDI: ffff888005a7f080 RBP: ffff888011dfc540 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff82e508e0 R11: 0000000000000005 R12: ffff88800ddfbe58 R13: ffff888005a7f080 R14: ffff888005a7f158 R15: ffff888005a7f158 FS: 0000000000000000(0000) GS:ffff88803ea80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000020 CR3: 0000000002e22006 CR4: 0000000000370ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ? __die_body.cold+0x19/0x26 ? page_fault_oops+0x13e/0x2b0 ? _printk+0x58/0x73 ? do_user_addr_fault+0x5f/0x750 ? exc_page_fault+0x76/0x240 ? asm_exc_page_fault+0x22/0x30 ? btrfs_bio_end_io+0xae/0xc0 [btrfs] ? btrfs_log_dev_io_error+0x7f/0x90 [btrfs] btrfs_orig_write_end_io+0x51/0x90 [btrfs] dm_submit_bio+0x5c2/0xa50 [dm_mod] ? find_held_lock+0x2b/0x80 ? blk_try_enter_queue+0x90/0x1e0 __submit_bio+0xe0/0x130 ? ktime_get+0x10a/0x160 ? lockdep_hardirqs_on+0x74/0x100 submit_bio_noacct_nocheck+0x199/0x410 btrfs_submit_bio+0x7d/0x150 [btrfs] btrfs_submit_chunk+0x1a1/0x6d0 [btrfs] ? lockdep_hardirqs_on+0x74/0x100 ? __folio_start_writeback+0x10/0x2c0 btrfs_submit_bbio+0x1c/0x40 [btrfs] submit_one_bio+0x44/0x60 [btrfs] submit_extent_folio+0x13f/0x330 [btrfs] ? btrfs_set_range_writeback+0xa3/0xd0 [btrfs] extent_writepage_io+0x18b/0x360 [btrfs] extent_write_locked_range+0x17c/0x340 [btrfs] ? __pfx_end_bbio_data_write+0x10/0x10 [btrfs] run_delalloc_cow+0x71/0xd0 [btrfs] btrfs_run_delalloc_range+0x176/0x500 [btrfs] ? find_lock_delalloc_range+0x119/0x260 [btrfs] writepage_delalloc+0x2ab/0x480 [btrfs] extent_write_cache_pages+0x236/0x7d0 [btrfs] btrfs_writepages+0x72/0x130 [btrfs] do_writepages+0xd4/0x240 ? find_held_lock+0x2b/0x80 ? wbc_attach_and_unlock_inode+0x12c/0x290 ? wbc_attach_and_unlock_inode+0x12c/0x29 ---truncated--- ## Where it's fixed | Platform | Product | Fixed in | Fix | Released | |---|---|---|---|---| | Linux | dtb-aarch64 opensuse-leap 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 | | Linux | kernel-64kb opensuse-leap 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 | | Linux | kernel-64kb sles 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 | | Linux | kernel-azure opensuse-leap 15.6 | 6.4.0-150600.8.20.1 | [SUSE-SU-2024:4316-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4316-1.md) | Dec 13, 2024 | | Linux | kernel-azure sles 15.6 | 6.4.0-150600.8.20.1 | [SUSE-SU-2024:4316-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4316-1.md) | Dec 13, 2024 | | Linux | kernel-coco sles 15.6 | 6.4.0-15061.9.coco15sp6.1 | [SUSE-SU-2024:4387-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4387-1.md) | Dec 19, 2024 | | Linux | kernel-coco_debug sles 15.6 | 6.4.0-15061.9.coco15sp6.1 | [SUSE-SU-2024:4387-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4387-1.md) | Dec 19, 2024 | | Linux | kernel-debug opensuse-leap 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 | | Linux | kernel-default opensuse-leap 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 | | Linux | kernel-default sles 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 | | Linux | kernel-default-base opensuse-leap 15.6 | 6.4.0-150600.23.30.1.150600.12.12.6 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 | | Linux | kernel-default-base sles 15.6 | 6.4.0-150600.23.30.1.150600.12.12.6 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 | | Linux | kernel-docs opensuse-leap 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 | | Linux | kernel-docs sles 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 | | Linux | kernel-kvmsmall opensuse-leap 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 | | Linux | kernel-livepatch-SLE15-SP6-RT_Update_6 sles 15.6 | 1-150600.1.3.1 | [SUSE-SU-2024:4314-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4314-1.md) | Dec 13, 2024 | | Linux | kernel-livepatch-SLE15-SP6_Update_6 sles 15.6 | 1-150600.13.3.5 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 | | Linux | kernel-obs-build opensuse-leap 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 | | Linux | kernel-obs-build sles 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 | | Linux | kernel-obs-qa opensuse-leap 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 | | Linux | kernel-rt opensuse-leap 15.6 | 6.4.0-150600.10.20.1 | [SUSE-SU-2024:4314-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4314-1.md) | Dec 13, 2024 | | Linux | kernel-rt_debug opensuse-leap 15.6 | 6.4.0-150600.10.20.1 | [SUSE-SU-2024:4314-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4314-1.md) | Dec 13, 2024 | | Linux | kernel-source opensuse-leap 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 | | Linux | kernel-source sles 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 | | Linux | kernel-source-azure opensuse-leap 15.6 | 6.4.0-150600.8.20.1 | [SUSE-SU-2024:4316-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4316-1.md) | Dec 13, 2024 | | Linux | kernel-source-azure sles 15.6 | 6.4.0-150600.8.20.1 | [SUSE-SU-2024:4316-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4316-1.md) | Dec 13, 2024 | | Linux | kernel-source-coco sles 15.6 | 6.4.0-15061.9.coco15sp6.1 | [SUSE-SU-2024:4387-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4387-1.md) | Dec 19, 2024 | | Linux | kernel-source-rt opensuse-leap 15.6 | 6.4.0-150600.10.20.1 | [SUSE-SU-2024:4314-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4314-1.md) | Dec 13, 2024 | | Linux | kernel-syms opensuse-leap 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 | | Linux | kernel-syms sles 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 | | Linux | kernel-syms-azure opensuse-leap 15.6 | 6.4.0-150600.8.20.1 | [SUSE-SU-2024:4316-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4316-1.md) | Dec 13, 2024 | | Linux | kernel-syms-azure sles 15.6 | 6.4.0-150600.8.20.1 | [SUSE-SU-2024:4316-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4316-1.md) | Dec 13, 2024 | | Linux | kernel-syms-coco sles 15.6 | 6.4.0-15061.9.coco15sp6.1 | [SUSE-SU-2024:4387-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4387-1.md) | Dec 19, 2024 | | Linux | kernel-syms-rt opensuse-leap 15.6 | 6.4.0-150600.10.20.1 | [SUSE-SU-2024:4314-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4314-1.md) | Dec 13, 2024 | | Linux | kernel-zfcpdump opensuse-leap 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 | | Linux | kernel-zfcpdump sles 15.6 | 6.4.0-150600.23.30.1 | [SUSE-SU-2024:4318-1](https://patchblox.com/security/data/fix/linux/suse-su-2024-4318-1.md) | Dec 13, 2024 | | Linux | linux Debian 13.5 (trixie) | 6.11.7-1 | [DEBIAN-CVE-2024-50225](https://patchblox.com/security/data/fix/linux/debian-cve-2024-50225.md) | Nov 9, 2024 | | Linux | linux Debian 14 | 6.11.7-1 | [DEBIAN-CVE-2024-50225](https://patchblox.com/security/data/fix/linux/debian-cve-2024-50225.md) | Nov 9, 2024 | --- Data as of 2026-11-09T01:18:40Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.