Description
In the Linux kernel, the following vulnerability has been resolved: nios2: ensure that memblock.current_limit is set when setting pfn limits On nios2, with CONFIG_FLATMEM set, the kernel relies on memblock_get_current_limit() to determine the limits of mem_map, in particular for max_low_pfn. Unfortunately, memblock.current_limit is only default initialized to MEMBLOCK_ALLOC_ANYWHERE at this point of the bootup, potentially leading to situations where max_low_pfn can erroneously exceed the value of max_pfn and, thus, the valid range of available DRAM. This can in turn cause kernel-level paging failures, e.g.: [ 76.900000] Unable to handle kernel paging request at virtual address 20303000 [ 76.900000] ea = c0080890, ra = c000462c, cause = 14 [ 76.900000] Kernel panic - not syncing: Oops [ 76.900000] ---[ end Kernel panic - not syncing: Oops ]--- This patch fixes this by pre-calculating memblock.current_limit based on the upper limits of the available memory ranges via adjust_lowmem_bounds, a simplified version of the equivalent implementation within the arm architecture.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
7f7bc20bc41a4fbcd2db75b375ac95e5faf958ae to < 25f09699edd360b534ccae16bc276c3b52c471f3affected7f7bc20bc41a4fbcd2db75b375ac95e5faf958ae to < 5c3e38a367822f036227dd52bac82dc4a05157e2affected7f7bc20bc41a4fbcd2db75b375ac95e5faf958ae to < b1ec9faef7e36269ca3ec890972a78effbaeb975affected7f7bc20bc41a4fbcd2db75b375ac95e5faf958ae to < 90f5f715550e07cd6a51f80fc3f062d832c8c997affected7f7bc20bc41a4fbcd2db75b375ac95e5faf958ae to < 8912814f14e298b83df072fecc1f7ed1b63b1b2caffected7f7bc20bc41a4fbcd2db75b375ac95e5faf958ae to < a20b83cf45be2057f3d073506779e52c7fa17f94affected
Linux Linux
Default version status: affected
5.12affected0 to < 5.12unaffected5.15.196 to ≤ 5.15.*unaffected6.1.158 to ≤ 6.1.*unaffected6.6.115 to ≤ 6.6.*unaffected6.12.56 to ≤ 6.12.*unaffected6.17.6 to ≤ 6.17.*unaffected6.18 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/25f09699edd360b534ccae16bc276c3b52c471f3 ↗
- https://git.kernel.org/stable/c/5c3e38a367822f036227dd52bac82dc4a05157e2 ↗
- https://git.kernel.org/stable/c/b1ec9faef7e36269ca3ec890972a78effbaeb975 ↗
- https://git.kernel.org/stable/c/90f5f715550e07cd6a51f80fc3f062d832c8c997 ↗
- https://git.kernel.org/stable/c/8912814f14e298b83df072fecc1f7ed1b63b1b2c ↗
- https://git.kernel.org/stable/c/a20b83cf45be2057f3d073506779e52c7fa17f94 ↗