CVE-2024-49887

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 getnewsegment of _allocatenewsegment+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:getnewsegment fs/f2fs/segment.c:2748 [inline] RIP: 0010:newcurseg+0x1f61/0x1f70 fs/f2fs/segment.c:2836 Call Trace: _allocatenewsegment+0x1ce/0x940 fs/f2fs/segment.c:3167 f2fsallocatenewsection fs/f2fs/segment.c:3181 [inline] f2fsallocatepinningsection+0xfa/0x4e0 fs/f2fs/segment.c:3195 f2fsexpandinodedata+0x5d6/0xbb0 fs/f2fs/file.c:1799 f2fsfallocate+0x448/0x960 fs/f2fs/file.c:1903 vfsfallocate+0x553/0x6c0 fs/open.c:334 dovfsioctl+0x2592/0x2e50 fs/ioctl.c:886 _dosysioctl fs/ioctl.c:905 [inline] _sesysioctl+0x81/0x170 fs/ioctl.c:893 dosyscallx64 arch/x86/entry/common.c:52 [inline] dosyscall64+0xf3/0x230 arch/x86/entry/common.c:83 entrySYSCALL64afterhwframe+0x77/0x7f RIP: 0010:getnewsegment 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.