CVE-2026-89765

Summary

In the Linux kernel, the following vulnerability has been resolved:

timers/itimer: Zero-init old itimerval before copy to userspace

On native sparc64, struct __kernel_old_timeval contains a four-byte hole after tv_usec because tv_sec is 64-bit while __kernel_suseconds_t is 32-bit. put_itimerval() fills only the named fields in a stack-allocated __kernel_old_itimerval and copies the entire object to userspace, so getitimer() can expose the two padding holes.

Zero-initialize the aggregate before assigning the fields so implicit padding is deterministic before it crosses the user/kernel boundary.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 6d4b937251386d9c6f968e7802f0cb16a8523772affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 4ea70146ab9376092297eb8b622ef1792797f2cfaffected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < a17b345daff46fec4af9f1ecbdf350208016dd15affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < bdfda99c5763822a9a888e8af0ad7d9312ffcfe2affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 4c66719dd1e4023c5e3f7d050f1bbefec3dfbeb4affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 2bf5e8f7c9bf4ad3be343a9a6e3e50a34264d25eaffected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 00ef529a5402f41eb1d227916437e237450719f9affected
LinuxLinux1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 < 18c7d85864e554adc8fad1e8d2e9d2cb6c3911c8affected
LinuxLinux2.6.12affected
LinuxLinux0 < 2.6.12unaffected
LinuxLinux5.10.270 <= 5.10.*unaffected
LinuxLinux5.15.221 <= 5.15.*unaffected
LinuxLinux6.1.188 <= 6.1.*unaffected
LinuxLinux6.6.157 <= 6.6.*unaffected
LinuxLinux6.12.109 <= 6.12.*unaffected
LinuxLinux6.18.50 <= 6.18.*unaffected
LinuxLinux7.2.4 <= 7.2.*unaffected
LinuxLinux7.3-rc1 <= *unaffected

Weaknesses

References