Affected: Alpaquita:23: linux-lts, Alpaquita:25: linux-lts, Alpaquita:stream: linux-lts

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

fs/ntfs3: resize log->one_page_buf when adopting on-disk page size

log_replay() allocates log->one_page_buf using the page size that was chosen from the host PAGE_SIZE:

log->one_page_buf = kmalloc(log->page_size, GFP_NOFS);

Later, when a restart area is found, the log page size recorded on disk is adopted:

t32 = le32_to_cpu(log->rst_info.r_page->sys_page_size); if (log->page_size != t32) { log->l_size = log->orig_file_size; log->page_size = norm_file_page(t32, &log->l_size, t32 == DefaultLogPageSize); }

If the on-disk page size is larger than the size used for the initial allocation, log->page_size grows but one_page_buf is left at its original, smaller size. A subsequent unaligned read_log_page() then reads log->page_size bytes into the undersized scratch buffer:

page_buf = page_off ? log->one_page_buf : *buffer; err = ntfs_read_run_nb_ra(ni->mi.sbi, &ni->file.run, page_vbo, page_buf, log->page_size, NULL, &log->read_ahead);

overflowing the allocation. This is reachable when mounting a dirty NTFS volume whose log was formatted with a page size larger than the buffer initially allocated on the mounting host (for example a 64K-log volume mounted on a host that allocated a 4K scratch buffer).

Grow one_page_buf when the adopted on-disk page size exceeds the size used for the initial allocation. On krealloc() failure the original buffer is left intact and freed by the existing erro…

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

fs/ntfs3: resize log->one_page_buf when adopting on-disk page size

log_replay() allocates log->one_page_buf using the page size that was chosen from the host PAGE_SIZE:

log->one_page_buf = kmalloc(log->page_size, GFP_NOFS);

Later, when a restart area is found, the log page size recorded on disk is adopted:

t32 = le32_to_cpu(log->rst_info.r_page->sys_page_size); if (log->page_size != t32) { log->l_size = log->orig_file_size; log->page_size = norm_file_page(t32, &log->l_size, t32 == DefaultLogPageSize); }

If the on-disk page size is larger than the size used for the initial allocation, log->page_size grows but one_page_buf is left at its original, smaller size. A subsequent unaligned read_log_page() then reads log->page_size bytes into the undersized scratch buffer:

page_buf = page_off ? log->one_page_buf : *buffer; err = ntfs_read_run_nb_ra(ni->mi.sbi, &ni->file.run, page_vbo, page_buf, log->page_size, NULL, &log->read_ahead);

overflowing the allocation. This is reachable when mounting a dirty NTFS volume whose log was formatted with a page size larger than the buffer initially allocated on the mounting host (for example a 64K-log volume mounted on a host that allocated a 4K scratch buffer).

Grow one_page_buf when the adopted on-disk page size exceeds the size used for the initial allocation. On krealloc() failure the original buffer is left intact and freed by the existing erro…

Affected: Ubuntu:16.04:LTS: linux-hwe-edge, Ubuntu:18.04:LTS: linux-aws-5.0, Ubuntu:18.04:LTS: linux-aws-5.3, Ubuntu:18.04:LTS: linux-azure, Ubuntu:18.04:LTS: linux-azure-5.3, Ubuntu:18.04:LTS: linux-azure-edge, Ubuntu:18.04:LTS: linux-gcp, Ubuntu:18.04:LTS: linux-gcp-5.3, Ubuntu:18.04:LTS: linux-gke-4.15, Ubuntu:18.04:LTS: linux-gke-5.4 and 193 more

In the Linux kernel, the following vulnerability has been resolved: fs/ntfs3: resize log->one_page_buf when adopting on-disk page size log_replay() allocates log->one_page_buf using the page size that was chosen from the host PAGE_SIZE: log->one_page_buf = kmalloc(log->page_size, GFP_NOFS); Later, when a restart area is found, the log page size recorded on disk is adopted: t32 = le32_to_cpu(log->rst_info.r_page->sys_page_size); if (log->page_size != t32) { log->l_size = log->orig_file_size; log->page_size = norm_file_page(t32, &log->l_size, t32 == DefaultLogPageSize); } If the on-disk page size is larger than the size used for the initial allocation, log->page_size grows but one_page_buf is left at its original, smaller size. A subsequent unaligned read_log_page() then reads log->page_size bytes into the undersized scratch buffer: page_buf = page_off ? log->one_page_buf : *buffer; err = ntfs_read_run_nb_ra(ni->mi.sbi, &ni->file.run, page_vbo, page_buf, log->page_size, NULL, &log->read_ahead); overflowing the allocation. This is reachable when mounting a dirty NTFS volume whose log was formatted with a page size larger than the buffer initially allocated on the mounting host (for example a 64K-log volume mounted on a host that allocated a 4K scratch buffer). Grow one_page_buf when the adopted on-disk page size exceeds the size used for the initial allocation. On krealloc() failure the original buffer is left intact and freed by the existing error path.

Ein Angreifer kann mehrere Schwachstellen in Linux Kernel ausnutzen, um root Rechte zu erlangen, um einen Denial of Service herbeizuführen oder einen nicht näher spezifizierten Angriff durchzuführen.