cbcvebase.
CVE-2024-47691
published 2024-10-21

CVE-2024-47691: In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to avoid use-after-free in f2fs_stop_gc_thread() syzbot reports a f2fs bug as…

PriorityP339high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.24%
14.9th percentile
In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to avoid use-after-free in f2fs_stop_gc_thread() syzbot reports a f2fs bug as below: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 print_report+0xe8/0x550 mm/kasan/report.c:491 kasan_report+0x143/0x180 mm/kasan/report.c:601 kasan_check_range+0x282/0x290 mm/kasan/generic.c:189 instrument_atomic_read_write include/linux/instrumented.h:96 [inline] atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:252 [inline] __refcount_add include/linux/refcount.h:184 [inline] __refcount_inc include/linux/refcount.h:241 [inline] refcount_inc include/linux/refcount.h:258 [inline] get_task_struct include/linux/sched/task.h:118 [inline] kthread_stop+0xca/0x630 kernel/kthread.c:704 f2fs_stop_gc_thread+0x65/0xb0 fs/f2fs/gc.c:210 f2fs_do_shutdown+0x192/0x540 fs/f2fs/file.c:2283 f2fs_ioc_shutdown fs/f2fs/file.c:2325 [inline] __f2fs_ioctl+0x443a/0xbe60 fs/f2fs/file.c:4325 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/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 The root cause is below race condition, it may cause use-after-free issue in sbi->gc_th pointer. - remount - f2fs_remount - f2fs_stop_gc_thread - kfree(gc_th) - f2fs_ioc_shutdown - f2fs_do_shutdown - f2fs_stop_gc_thread - kthread_stop(gc_th->f2fs_gc_task) : sbi->gc_thread = NULL; We will call f2fs_do_shutdown() in two paths: - for f2fs_ioc_shutdown() path, we should grab sb->s_umount semaphore for fixing. - for f2fs_shutdown() path, it's safe since caller has already grabbed sb->s_umount semaphore.

Affected

20 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.11.2-1 (forky)linux 6.11.2-1 (forky)
linuxlinux
linuxlinux>= 7950e9ac638e84518fbdd5c930939ad46a1068c5 < fc18e655b62ac6bc9f12f5de0d749b4a3fe1e812fc18e655b62ac6bc9f12f5de0d749b4a3fe1e812
linuxlinux>= 7950e9ac638e84518fbdd5c930939ad46a1068c5 < 7c339dee7eb0f8e4cadc317c595f898ef04dae307c339dee7eb0f8e4cadc317c595f898ef04dae30
linuxlinux>= 7950e9ac638e84518fbdd5c930939ad46a1068c5 < d79343cd66343709e409d96b2abb139a0a55ce34d79343cd66343709e409d96b2abb139a0a55ce34
linuxlinux>= 7950e9ac638e84518fbdd5c930939ad46a1068c5 < c7f114d864ac91515bb07ac271e9824a20f5ed95c7f114d864ac91515bb07ac271e9824a20f5ed95
linuxlinux_kernel>= 0 < 6.11.2-16.11.2-1
linuxlinux_kernel>= 0 < 6.11.2-16.11.2-1
linuxlinux_kernel>= 0 < 5.15.0-164.1745.15.0-164.174
linuxlinux_kernel>= 0 < 6.8.0-54.566.8.0-54.56
linuxlinux_kernel>= 0 < 6.11.0-18.186.11.0-18.18
linuxlinux_kernel>= 0 < 5.4.0-224.2445.4.0-224.244
linuxlinux_kernel>= 4.16 < 6.6.546.6.54
linuxlinux_kernel>= 6.11 < 6.11.26.11.2
linuxlinux_kernel>= 6.7 < 6.10.136.10.13
msrcazl3_kernel_6.6.51.1-5_on_azure_linux_3.0
msrcazl3_kernel_6.6.56.1-5_on_azure_linux_3.0
msrcazure_linux_3.0_arm
msrcazure_linux_3.0_x64
msrccbl2_kernel_5.15.180.1-1_on_cbl_mariner_2.0

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv8.8HIGH
vendor_ubuntu8.8HIGH
vendor_debian7.8HIGH
vendor_msrc7.8HIGH
vendor_redhat7.8HIGH
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