CVE-2022-48635

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> fsdax: Fix infinite loop in dax_iomap_rw()<br /> <br /> I got an infinite loop and a WARNING report when executing a tail command<br /> in virtiofs.<br /> <br /> WARNING: CPU: 10 PID: 964 at fs/iomap/iter.c:34 iomap_iter+0x3a2/0x3d0<br /> Modules linked in:<br /> CPU: 10 PID: 964 Comm: tail Not tainted 5.19.0-rc7<br /> Call Trace:<br /> <br /> dax_iomap_rw+0xea/0x620<br /> ? __this_cpu_preempt_check+0x13/0x20<br /> fuse_dax_read_iter+0x47/0x80<br /> fuse_file_read_iter+0xae/0xd0<br /> new_sync_read+0xfe/0x180<br /> ? 0xffffffff81000000<br /> vfs_read+0x14d/0x1a0<br /> ksys_read+0x6d/0xf0<br /> __x64_sys_read+0x1a/0x20<br /> do_syscall_64+0x3b/0x90<br /> entry_SYSCALL_64_after_hwframe+0x63/0xcd<br /> <br /> The tail command will call read() with a count of 0. In this case,<br /> iomap_iter() will report this WARNING, and always return 1 which casuing<br /> the infinite loop in dax_iomap_rw().<br /> <br /> Fixing by checking count whether is 0 in dax_iomap_rw().