CVE-2023-53485 fs: jfs: Fix UBSAN: array-index-out-of-bounds in dbAllocDmapLev

In the Linux kernel, the following vulnerability has been resolved: fs: jfs: Fix UBSAN: array-index-out-of-bounds in dbAllocDmapLev Syzkaller reported the following issue: UBSAN: array-index-out-of-bounds in fs/jfs/jfsdmap.c:1965:6 index -84 is out of range for type 's8341' aka 'signed char341'...

CVE-2023-53485

CVE-2023-53485 affects the Linux kernel JFS code path. The UBSAN out-of-bounds access in fs/jfs/jfs_dmap.c:1965 was triggered when dbAllocDmapLev accessed dp->tree.stree[leafidx + LEAFIND] with a negative leafidx. The patch adds a guard in dbAllocDmapLev to return an I/O error if leafidx is ne...