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| author | Demi Marie Obenour <demi@invisiblethingslab.com> | 2023-06-03 16:52:39 +0200 |
|---|---|---|
| committer | Mike Snitzer <snitzer@kernel.org> | 2023-06-23 16:31:49 +0200 |
| commit | b60528d9e68113e2c297c3a45102332cb1d3e608 (patch) | |
| tree | 08dc9427c93aa9008597fe048a70335647a45f81 /drivers/md | |
| parent | Documentation: dm-integrity: Document an example of how the tunables relate. (diff) | |
| download | linux-b60528d9e68113e2c297c3a45102332cb1d3e608.tar.xz linux-b60528d9e68113e2c297c3a45102332cb1d3e608.zip | |
dm ioctl: Check dm_target_spec is sufficiently aligned
Otherwise subsequent code, if given malformed input, could dereference
a misaligned 'struct dm_target_spec *'.
Signed-off-by: Demi Marie Obenour <demi@invisiblethingslab.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> # use %zu
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/dm-ioctl.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c index 8ba4cbb92351..3a6989b7817d 100644 --- a/drivers/md/dm-ioctl.c +++ b/drivers/md/dm-ioctl.c @@ -1394,6 +1394,15 @@ static inline blk_mode_t get_mode(struct dm_ioctl *param) static int next_target(struct dm_target_spec *last, uint32_t next, void *end, struct dm_target_spec **spec, char **target_params) { + static_assert(__alignof__(struct dm_target_spec) <= 8, + "struct dm_target_spec must not require more than 8-byte alignment"); + + if (next % __alignof__(struct dm_target_spec)) { + DMERR("Next dm_target_spec (offset %u) is not %zu-byte aligned", + next, __alignof__(struct dm_target_spec)); + return -EINVAL; + } + *spec = (struct dm_target_spec *) ((unsigned char *) last + next); *target_params = (char *) (*spec + 1); |