VulnerabilityAnalyzed

CVE-2021-47007

MEDIUM 5.5EPSS 0.24%

Does this matter?

Lower severity and a low EPSS score (0.24%). Track it; it rarely justifies an emergency change on its own.

Description

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix panic during f2fs_resize_fs() f2fs_resize_fs() hangs in below callstack with testcase: - mkfs 16GB image & mount image - dd 8GB fileA - dd 8GB fileB - sync - rm fileA - sync - resize filesystem to 8GB kernel BUG at segment.c:2484! Call Trace: allocate_segment_by_default+0x92/0xf0 [f2fs] f2fs_allocate_data_block+0x44b/0x7e0 [f2fs] do_write_page+0x5a/0x110 [f2fs] f2fs_outplace_write_data+0x55/0x100 [f2fs] f2fs_do_write_data_page+0x392/0x850 [f2fs] move_data_page+0x233/0x320 [f2fs] do_garbage_collect+0x14d9/0x1660 [f2fs] free_segment_range+0x1f7/0x310 [f2fs] f2fs_resize_fs+0x118/0x330 [f2fs] __f2fs_ioctl+0x487/0x3680 [f2fs] __x64_sys_ioctl+0x8e/0xd0 do_syscall_64+0x33/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xa9 The root cause is we forgot to check that whether we have enough space in resized filesystem to store all valid blocks in before-resizing filesystem, then allocator will run out-of-space during block migration in free_segment_range().

CVSS 3.1: 5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS: 0.24% probability · 15th percentile
CISA KEV: Not listed
Weakness: CWE-754
Affected: linux/linux kernel
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.