CVE-2026-46294

Description

In the Linux kernel, the following vulnerability has been resolved: dm: fix a buffer overflow in ioctl processing Tony Asleson (using Claude) found a buffer overflow in dm-ioctl in the function retrieve_status: 1. The code in retrieve_status checks that the output string fits into the output buffer and writes the output string there 2. Then, the code aligns the "outptr" variable to the next 8-byte boundary: outptr = align_ptr(outptr); 3. The alignment doesn't check overflow, so outptr could point past the buffer end 4. The "for" loop is iterated again, it executes: remaining = len - (outptr - outbuf); 5. If "outptr" points past "outbuf + len", the arithmetics wraps around and the variable "remaining" contains unusually high number 6. With "remaining" being high, the code writes more data past the end of the buffer Luckily, this bug has no security implications because: 1. Only root can issue device mapper ioctls 2. The commonly used libraries that communicate with device mapper (libdevmapper and devicemapper-rs) use buffer size that is aligned to 8 bytes - thus, "outptr = align_ptr(outptr)" can't overshoot the input buffer and the bug can't happen accidentally

PUBLISHED Reserved 2026-05-13 | Published 2026-06-08 | Updated 2026-06-09 | Assigner Linux

Product status

References

git.kernel.org/...c/c8c5311237448f6ffeecc9aec2362e3692623668

git.kernel.org/...c/448ee8fb79c26a26599ffa4b2adeb4322d3d3d8c

git.kernel.org/...c/526ff9126a0ae087b65726e1faf31114c718020d

git.kernel.org/...c/f0b0b09d9840838ae77ccdd6a62de0daef4e6e0a

git.kernel.org/...c/d271631023cbe1cbe7c31a0275ab797883be6e0a

git.kernel.org/...c/5af6a879e915ae7bcd83695c316ebb32e1c61bc2

git.kernel.org/...c/8daa6c708ef524089ae43f2aed9190acb26d7df8

git.kernel.org/...c/2fa49cc884f6496a915c35621ba4da35649bf159

cve.org (CVE-2026-46294)

nvd.nist.gov (CVE-2026-46294)

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