发布于3月6日3月6日 Members SUSE: CVE-2023-52737: SUSE Linux Security Advisory Severity 5 CVSS (AV:L/AC:L/Au:S/C:N/I:N/A:C) Published 05/21/2024 Created 07/10/2024 Added 07/10/2024 Modified 01/28/2025 Description In the Linux kernel, the following vulnerability has been resolved: btrfs: lock the inode in shared mode before starting fiemap Currently fiemap does not take the inode's lock (VFS lock), it only locks a file range in the inode's io tree. This however can lead to a deadlock if we have a concurrent fsync on the file and fiemap code triggers a fault when accessing the user space buffer with fiemap_fill_next_extent(). The deadlock happens on the inode's i_mmap_lock semaphore, which is taken both by fsync and btrfs_page_mkwrite(). This deadlock was recently reported by syzbot and triggers a trace like the following: task:syz-executor361 state:D stack:20264 pid:5668ppid:5119 flags:0x00004004 Call Trace: <TASK> context_switch kernel/sched/core.c:5293 [inline] __schedule+0x995/0xe20 kernel/sched/core.c:6606 schedule+0xcb/0x190 kernel/sched/core.c:6682 wait_on_state fs/btrfs/extent-io-tree.c:707 [inline] wait_extent_bit+0x577/0x6f0 fs/btrfs/extent-io-tree.c:751 lock_extent+0x1c2/0x280 fs/btrfs/extent-io-tree.c:1742 find_lock_delalloc_range+0x4e6/0x9c0 fs/btrfs/extent_io.c:488 writepage_delalloc+0x1ef/0x540 fs/btrfs/extent_io.c:1863 __extent_writepage+0x736/0x14e0 fs/btrfs/extent_io.c:2174 extent_write_cache_pages+0x983/0x1220 fs/btrfs/extent_io.c:3091 extent_writepages+0x219/0x540 fs/btrfs/extent_io.c:3211 do_writepages+0x3c3/0x680 mm/page-writeback.c:2581 filemap_fdatawrite_wbc+0x11e/0x170 mm/filemap.c:388 __filemap_fdatawrite_range mm/filemap.c:421 [inline] filemap_fdatawrite_range+0x175/0x200 mm/filemap.c:439 btrfs_fdatawrite_range fs/btrfs/file.c:3850 [inline] start_ordered_ops fs/btrfs/file.c:1737 [inline] btrfs_sync_file+0x4ff/0x1190 fs/btrfs/file.c:1839 generic_write_sync include/linux/fs.h:2885 [inline] btrfs_do_write_iter+0xcd3/0x1280 fs/btrfs/file.c:1684 call_write_iter include/linux/fs.h:2189 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x7dc/0xc50 fs/read_write.c:584 ksys_write+0x177/0x2a0 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f7d4054e9b9 RSP: 002b:00007f7d404fa2f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f7d405d87a0 RCX: 00007f7d4054e9b9 RDX: 0000000000000090 RSI: 0000000020000000 RDI: 0000000000000006 RBP: 00007f7d405a51d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 61635f65646f6e69 R13: 65646f7475616f6e R14: 7261637369646f6e R15: 00007f7d405d87a8 </TASK> INFO: task syz-executor361:5697 blocked for more than 145 seconds. Not tainted 6.2.0-rc3-syzkaller-00376-g7c6984405241 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor361 state:D stack:21216 pid:5697ppid:5119 flags:0x00004004 Call Trace: <TASK> context_switch kernel/sched/core.c:5293 [inline] __schedule+0x995/0xe20 kernel/sched/core.c:6606 schedule+0xcb/0x190 kernel/sched/core.c:6682 rwsem_down_read_slowpath+0x5f9/0x930 kernel/locking/rwsem.c:1095 __down_read_common+0x54/0x2a0 kernel/locking/rwsem.c:1260 btrfs_page_mkwrite+0x417/0xc80 fs/btrfs/inode.c:8526 do_page_mkwrite+0x19e/0x5e0 mm/memory.c:2947 wp_page_shared+0x15e/0x380 mm/memory.c:3295 handle_pte_fault mm/memory.c:4949 [inline] __handle_mm_fault mm/memory.c:5073 [inline] handle_mm_fault+0x1b79/0x26b0 mm/memory.c:5219 do_user_addr_fault+0x69b/0xcb0 arch/x86/mm/fault.c:1428 handle_page_fault arch/x86/mm/fault.c:1519 [inline] exc_page_fault+0x7a/0x110 arch/x86/mm/fault.c:1575 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:570 RIP: 0010:copy_user_short_string+0xd/0x40 arch/x86/lib/copy_user_64.S:233 Code: 74 0a 89 (...) RSP: 0018:ffffc9000570f330 EFLAGS: 000502 ---truncated--- Solution(s) suse-upgrade-cluster-md-kmp-64kb suse-upgrade-cluster-md-kmp-azure suse-upgrade-cluster-md-kmp-default suse-upgrade-cluster-md-kmp-rt suse-upgrade-dlm-kmp-64kb suse-upgrade-dlm-kmp-azure suse-upgrade-dlm-kmp-default suse-upgrade-dlm-kmp-rt suse-upgrade-dtb-allwinner suse-upgrade-dtb-altera suse-upgrade-dtb-amazon suse-upgrade-dtb-amd suse-upgrade-dtb-amlogic suse-upgrade-dtb-apm suse-upgrade-dtb-apple suse-upgrade-dtb-arm suse-upgrade-dtb-broadcom suse-upgrade-dtb-cavium suse-upgrade-dtb-exynos suse-upgrade-dtb-freescale suse-upgrade-dtb-hisilicon suse-upgrade-dtb-lg suse-upgrade-dtb-marvell suse-upgrade-dtb-mediatek suse-upgrade-dtb-nvidia suse-upgrade-dtb-qcom suse-upgrade-dtb-renesas suse-upgrade-dtb-rockchip suse-upgrade-dtb-socionext suse-upgrade-dtb-sprd suse-upgrade-dtb-xilinx suse-upgrade-gfs2-kmp-64kb suse-upgrade-gfs2-kmp-azure suse-upgrade-gfs2-kmp-default suse-upgrade-gfs2-kmp-rt suse-upgrade-kernel-64kb suse-upgrade-kernel-64kb-devel suse-upgrade-kernel-64kb-extra suse-upgrade-kernel-64kb-livepatch-devel suse-upgrade-kernel-64kb-optional suse-upgrade-kernel-azure suse-upgrade-kernel-azure-base suse-upgrade-kernel-azure-devel suse-upgrade-kernel-azure-extra suse-upgrade-kernel-azure-livepatch-devel suse-upgrade-kernel-azure-optional suse-upgrade-kernel-azure-vdso suse-upgrade-kernel-debug suse-upgrade-kernel-debug-devel suse-upgrade-kernel-debug-livepatch-devel suse-upgrade-kernel-debug-vdso suse-upgrade-kernel-default suse-upgrade-kernel-default-base suse-upgrade-kernel-default-base-rebuild suse-upgrade-kernel-default-devel suse-upgrade-kernel-default-extra suse-upgrade-kernel-default-livepatch suse-upgrade-kernel-default-livepatch-devel suse-upgrade-kernel-default-man suse-upgrade-kernel-default-optional suse-upgrade-kernel-default-vdso suse-upgrade-kernel-devel suse-upgrade-kernel-devel-azure suse-upgrade-kernel-devel-rt suse-upgrade-kernel-docs suse-upgrade-kernel-docs-html suse-upgrade-kernel-kvmsmall suse-upgrade-kernel-kvmsmall-devel suse-upgrade-kernel-kvmsmall-livepatch-devel suse-upgrade-kernel-kvmsmall-vdso suse-upgrade-kernel-macros suse-upgrade-kernel-obs-build suse-upgrade-kernel-obs-qa suse-upgrade-kernel-rt suse-upgrade-kernel-rt-devel suse-upgrade-kernel-rt-extra suse-upgrade-kernel-rt-livepatch suse-upgrade-kernel-rt-livepatch-devel suse-upgrade-kernel-rt-optional suse-upgrade-kernel-rt-vdso suse-upgrade-kernel-rt_debug suse-upgrade-kernel-rt_debug-devel suse-upgrade-kernel-rt_debug-livepatch-devel suse-upgrade-kernel-rt_debug-vdso suse-upgrade-kernel-source suse-upgrade-kernel-source-azure suse-upgrade-kernel-source-rt suse-upgrade-kernel-source-vanilla suse-upgrade-kernel-syms suse-upgrade-kernel-syms-azure suse-upgrade-kernel-syms-rt suse-upgrade-kernel-zfcpdump suse-upgrade-kselftests-kmp-64kb suse-upgrade-kselftests-kmp-azure suse-upgrade-kselftests-kmp-default suse-upgrade-kselftests-kmp-rt suse-upgrade-ocfs2-kmp-64kb suse-upgrade-ocfs2-kmp-azure suse-upgrade-ocfs2-kmp-default suse-upgrade-ocfs2-kmp-rt suse-upgrade-reiserfs-kmp-64kb suse-upgrade-reiserfs-kmp-azure suse-upgrade-reiserfs-kmp-default suse-upgrade-reiserfs-kmp-rt References https://attackerkb.com/topics/cve-2023-52737 CVE - 2023-52737