Bug 2320548 (CVE-2024-49887)

Summary: CVE-2024-49887 kernel: f2fs: fix to don't panic system for no free segment fault injection
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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Priority: medium    
Version: unspecifiedCC: dfreiber, drow, jburrell, vkumar
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Hardware: All   
OS: Linux   
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Bug Depends On: 2321047    
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Description OSIDB Bzimport 2024-10-21 19:09:59 UTC 
In the Linux kernel, the following vulnerability has been resolved:

f2fs: fix to don't panic system for no free segment fault injection

f2fs: fix to don't panic system for no free segment fault injection

syzbot reports a f2fs bug as below:

F2FS-fs (loop0): inject no free segment in get_new_segment of __allocate_new_segment+0x1ce/0x940 fs/f2fs/segment.c:3167
F2FS-fs (loop0): Stopped filesystem due to reason: 7
------------[ cut here ]------------
kernel BUG at fs/f2fs/segment.c:2748!
CPU: 0 UID: 0 PID: 5109 Comm: syz-executor304 Not tainted 6.11.0-rc6-syzkaller-00363-g89f5e14d05b4 #0
RIP: 0010:get_new_segment fs/f2fs/segment.c:2748 [inline]
RIP: 0010:new_curseg+0x1f61/0x1f70 fs/f2fs/segment.c:2836
Call Trace:
 __allocate_new_segment+0x1ce/0x940 fs/f2fs/segment.c:3167
 f2fs_allocate_new_section fs/f2fs/segment.c:3181 [inline]
 f2fs_allocate_pinning_section+0xfa/0x4e0 fs/f2fs/segment.c:3195
 f2fs_expand_inode_data+0x5d6/0xbb0 fs/f2fs/file.c:1799
 f2fs_fallocate+0x448/0x960 fs/f2fs/file.c:1903
 vfs_fallocate+0x553/0x6c0 fs/open.c:334
 do_vfs_ioctl+0x2592/0x2e50 fs/ioctl.c:886
 __do_sys_ioctl fs/ioctl.c:905 [inline]
 __se_sys_ioctl+0x81/0x170 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
RIP: 0010:get_new_segment fs/f2fs/segment.c:2748 [inline]
RIP: 0010:new_curseg+0x1f61/0x1f70 fs/f2fs/segment.c:2836

The root cause is when we inject no free segment fault into f2fs,
we should not panic system, fix it.
Comment 1 Robb Gatica 2024-10-22 16:39:05 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2024102117-CVE-2024-49887-04ba@gregkh/T