In the Linux kernel, the following vulnerability has been resolved: mtd: spi-nor: swp: Improve locking user experience In the case of the first block being locked (or the few first blocks), if the user want to fully unlock the device it has two possibilities: - either it asks to unlock the entire device, and this works; - or it asks to unlock just the block(s) that are currently locked, which fails. It fails because the conditions "can_be_top" and "can_be_bottom" are true. Indeed, in this case, we unlock everything, so the TB bit does not matter. However in the current implementation, use_top would be true (as this is the favourite option) and lock_len, which in practice should be reduced down to 0, is set to "nor->params->size - (ofs + len)" which is a positive number. This is wrong. An easy way is to simply add an extra condition. In the unlock() path, if we can achieve the same result from both sides, it means we unlock everything and lock_len must simply be 0. A comment is added to clarify that logic.

A flaw was found in the Linux kernel's `mtd: spi-nor: swp` component. When a user attempts to unlock specific blocks on a Serial Peripheral Interface (SPI) NOR flash device, particularly those at the beginning of the device, the operation may fail. This occurs due to an incorrect calculation of the `lock_len` parameter, which prevents the intended blocks from being unlocked. The consequence is that the user's request to unlock certain flash memory regions is not properly executed, potentially leading to unexpected device behavior or operational limitations.

Red Hat Enterprise Linux 10 Fix deferred kernel Red Hat Enterprise Linux 6 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel-rt Red Hat Enterprise Linux 8 Not affected kernel Red Hat Enterprise Linux 8 Not affected kernel-rt Red Hat Enterprise Linux 9 Fix deferred kernel Red Hat Enterprise Linux 9 Fix deferred kernel-rt https://www.cve.org/CVERecord?id=CVE-2026-72155 https://nvd.nist.gov/vuln/detail/CVE-2026-72155 https://lore.kernel.org/linux-cve-announce/2026081535-CVE-2026-72155-8ba3@gregkh/T