fs/jfs: Add check for negative db_l2nbperpage
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.8epss 0.3%
exploitation probability
0.3%top 82% of all CVEs
observed exploitation
nono source reports it
In the Linux kernel, the following vulnerability has been resolved:
fs/jfs: Add check for negative db_l2nbperpage
l2nbperpage is log2(number of blks per page), and the minimum legal
value should be 0, not negative.
In the case of l2nbperpage being negative, an error will occur
when subsequently used as shift exponent.
Syzbot reported this bug:
UBSAN: shift-out-of-bounds in fs/jfs/jfs_dmap.c:799:12
shift exponent -16777216 is negative
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Affected products
Linux · LinuxReferences
https://git.kernel.org/stable/c/0cb567e727339a192f9fd0db00781d73a91d15a6https://git.kernel.org/stable/c/1a7c53fdea1d189087544d9a606d249e93c4934bhttps://git.kernel.org/stable/c/491085258185ffc4fb91555b0dba895fe7656a45https://git.kernel.org/stable/c/524b4f203afcf87accfe387e846f33f916f0c907https://git.kernel.org/stable/c/525b861a008143048535011f3816d407940f4bfahttps://git.kernel.org/stable/c/5f148b16972e5f4592629b244d5109b15135f53fhttps://git.kernel.org/stable/c/8f2964df6bfce9d92d81ca552010b8677af8d9dchttps://git.kernel.org/stable/c/a81a56b4cbe3142cc99f6b98e8f9b3a631c768e1https://git.kernel.org/stable/c/cc61fcf7d1c99f148fe8ddfb5c6ed0bb75861f01