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: fix out-of-bounds read in read_log_rec_buf()

read_log_rec_buf() copies a log record into a caller buffer starting at

u32 off = lsn_to_page_off(log, lsn) + log->record_header_len;

log->record_header_len (and log->data_off, used for the following pages) comes verbatim from the on-disk restart area and is only checked for 8-byte alignment in is_rst_area_valid(), so off can exceed log->page_size. "tail = log->page_size - off" then underflows and memcpy() reads past the page_size-sized buffer returned by read_log_page(), spilling adjacent slab memory into the replay buffer.

This is reachable by mounting a crafted NTFS image:

BUG: KASAN: slab-out-of-bounds in read_log_rec_buf+0x216/0x580 Read of size 64 at addr ffff88800a877ff8 by task exploit/127 read_log_rec_buf fs/ntfs3/fslog.c:2299 log_replay fs/ntfs3/fslog.c:4216 ntfs_loadlog_and_replay fs/ntfs3/fsntfs.c:324 ntfs_fill_super fs/ntfs3/super.c:1392 get_tree_bdev_flags fs/super.c:1694 __x64_sys_mount fs/namespace.c:4360 The buggy address is located 4088 bytes to the right of the 4096-byte region [ffff88800a876000, ffff88800a877000)

Reject an in-page offset outside the current page before the copy.

[almaz.alexandrovich@paragon-software.com: replaced the >= sign with >]

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

fs/ntfs3: fix out-of-bounds read in read_log_rec_buf()

read_log_rec_buf() copies a log record into a caller buffer starting at

u32 off = lsn_to_page_off(log, lsn) + log->record_header_len;

log->record_header_len (and log->data_off, used for the following pages) comes verbatim from the on-disk restart area and is only checked for 8-byte alignment in is_rst_area_valid(), so off can exceed log->page_size. "tail = log->page_size - off" then underflows and memcpy() reads past the page_size-sized buffer returned by read_log_page(), spilling adjacent slab memory into the replay buffer.

This is reachable by mounting a crafted NTFS image:

BUG: KASAN: slab-out-of-bounds in read_log_rec_buf+0x216/0x580 Read of size 64 at addr ffff88800a877ff8 by task exploit/127 read_log_rec_buf fs/ntfs3/fslog.c:2299 log_replay fs/ntfs3/fslog.c:4216 ntfs_loadlog_and_replay fs/ntfs3/fsntfs.c:324 ntfs_fill_super fs/ntfs3/super.c:1392 get_tree_bdev_flags fs/super.c:1694 __x64_sys_mount fs/namespace.c:4360 The buggy address is located 4088 bytes to the right of the 4096-byte region [ffff88800a876000, ffff88800a877000)

Reject an in-page offset outside the current page before the copy.

[almaz.alexandrovich@paragon-software.com: replaced the >= sign with >]

kernel-devel-7.2.7-1.1 on GA media

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: fix out-of-bounds read in read_log_rec_buf() read_log_rec_buf() copies a log record into a caller buffer starting at u32 off = lsn_to_page_off(log, lsn) + log->record_header_len; log->record_header_len (and log->data_off, used for the following pages) comes verbatim from the on-disk restart area and is only checked for 8-byte alignment in is_rst_area_valid(), so off can exceed log->page_size. "tail = log->page_size - off" then underflows and memcpy() reads past the page_size-sized buffer returned by read_log_page(), spilling adjacent slab memory into the replay buffer. This is reachable by mounting a crafted NTFS image: BUG: KASAN: slab-out-of-bounds in read_log_rec_buf+0x216/0x580 Read of size 64 at addr ffff88800a877ff8 by task exploit/127 read_log_rec_buf fs/ntfs3/fslog.c:2299 log_replay fs/ntfs3/fslog.c:4216 ntfs_loadlog_and_replay fs/ntfs3/fsntfs.c:324 ntfs_fill_super fs/ntfs3/super.c:1392 get_tree_bdev_flags fs/super.c:1694 __x64_sys_mount fs/namespace.c:4360 The buggy address is located 4088 bytes to the right of the 4096-byte region [ffff88800a876000, ffff88800a877000) Reject an in-page offset outside the current page before the copy. [almaz.alexandrovich@paragon-software.com: replaced the >= sign with >]

Ein Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um Speicher zu beschädigen oder offenzulegen, den Kernel oder den Systemzustand zu manipulieren oder Denial-of-Service-Zustände, einschließlich Kernel-Abstürzen, zu verursachen.