diff options
| author | Sudhakar Kuppusamy <sudhakar@linux.ibm.com> | 2022-04-06 18:03:37 +0530 |
|---|---|---|
| committer | Daniel Kiper <daniel.kiper@oracle.com> | 2022-06-07 16:39:33 +0200 |
| commit | 4bd9877f62166b7e369773ab92fe24a39f6515f8 (patch) | |
| tree | c2a00260cd3af2497ec3200632ab0680fec48d61 | |
| parent | b26b4c08e7119281ff30d0fb4a6169bd2afa8fe4 (diff) | |
| download | grub-4bd9877f62166b7e369773ab92fe24a39f6515f8.tar.gz | |
fs/f2fs: Do not read past the end of nat journal entries
A corrupt f2fs file system could specify a nat journal entry count
that is beyond the maximum NAT_JOURNAL_ENTRIES.
Check if the specified nat journal entry count before accessing the
array, and throw an error if it is too large.
Signed-off-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
| -rw-r--r-- | grub-core/fs/f2fs.c | 21 |
1 files changed, 14 insertions, 7 deletions
diff --git a/grub-core/fs/f2fs.c b/grub-core/fs/f2fs.c index 8a9992ca9..63702214b 100644 --- a/grub-core/fs/f2fs.c +++ b/grub-core/fs/f2fs.c @@ -632,23 +632,27 @@ get_nat_journal (struct grub_f2fs_data *data) return err; } -static grub_uint32_t -get_blkaddr_from_nat_journal (struct grub_f2fs_data *data, grub_uint32_t nid) +static grub_err_t +get_blkaddr_from_nat_journal (struct grub_f2fs_data *data, grub_uint32_t nid, + grub_uint32_t *blkaddr) { grub_uint16_t n = grub_le_to_cpu16 (data->nat_j.n_nats); - grub_uint32_t blkaddr = 0; grub_uint16_t i; + if (n >= NAT_JOURNAL_ENTRIES) + return grub_error (GRUB_ERR_BAD_FS, + "invalid number of nat journal entries"); + for (i = 0; i < n; i++) { if (grub_le_to_cpu32 (data->nat_j.entries[i].nid) == nid) { - blkaddr = grub_le_to_cpu32 (data->nat_j.entries[i].ne.block_addr); + *blkaddr = grub_le_to_cpu32 (data->nat_j.entries[i].ne.block_addr); break; } } - return blkaddr; + return GRUB_ERR_NONE; } static grub_uint32_t @@ -656,10 +660,13 @@ get_node_blkaddr (struct grub_f2fs_data *data, grub_uint32_t nid) { struct grub_f2fs_nat_block *nat_block; grub_uint32_t seg_off, block_off, entry_off, block_addr; - grub_uint32_t blkaddr; + grub_uint32_t blkaddr = 0; grub_err_t err; - blkaddr = get_blkaddr_from_nat_journal (data, nid); + err = get_blkaddr_from_nat_journal (data, nid, &blkaddr); + if (err != GRUB_ERR_NONE) + return 0; + if (blkaddr) return blkaddr; |