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:
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().
[
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "unaffected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"fs/f2fs/gc.c"
],
"versions": [
{
"version": "b4b10061ef98",
"lessThan": "1c20a4896409",
"status": "affected",
"versionType": "git"
},
{
"version": "b4b10061ef98",
"lessThan": "860afd680d9c",
"status": "affected",
"versionType": "git"
},
{
"version": "b4b10061ef98",
"lessThan": "822054e5026c",
"status": "affected",
"versionType": "git"
},
{
"version": "b4b10061ef98",
"lessThan": "3ab0598e6d86",
"status": "affected",
"versionType": "git"
}
]
},
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "affected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"fs/f2fs/gc.c"
],
"versions": [
{
"version": "5.8",
"status": "affected"
},
{
"version": "0",
"lessThan": "5.8",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "5.10.38",
"lessThanOrEqual": "5.10.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "5.11.22",
"lessThanOrEqual": "5.11.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "5.12.5",
"lessThanOrEqual": "5.12.*",
"status": "unaffected",
"versionType": "custom"
},
{
"version": "5.13",
"lessThanOrEqual": "*",
"status": "unaffected",
"versionType": "original_commit_for_fix"
}
]
}
]