diff options
| author | Brian Behlendorf <[email protected]> | 2017-12-04 11:44:39 -0800 |
|---|---|---|
| committer | GitHub <[email protected]> | 2017-12-04 11:44:39 -0800 |
| commit | 72841b9fd957a392bb621393685b06dc042d4523 (patch) | |
| tree | 77e1918dc3ae43a657f5cb059e43ce29c8e25e5e | |
| parent | d4677269f286005768ae1a0fcd3389aa6015c4c7 (diff) | |
Preserve itx alloc size for zio_data_buf_free()
Using zio_data_buf_alloc() to allocate the itx's may be unsafe
because the itx->itx_lr.lrc_reclen field is not constant from
allocation to free. Using a different itx->itx_lr.lrc_reclen
size in zio_data_buf_free() can result in the allocation being
returned to the wrong kmem cache.
This issue can be avoided entirely by storing the allocation size
in itx->itx_size and using that for zio_data_buf_free().
Reviewed by: Prakash Surya <[email protected]>
Signed-off-by: Brian Behlendorf <[email protected]>
Closes #6912
| -rw-r--r-- | include/sys/zil.h | 1 | ||||
| -rw-r--r-- | module/zfs/zil.c | 7 |
2 files changed, 6 insertions, 2 deletions
diff --git a/include/sys/zil.h b/include/sys/zil.h index 11c7fb4a2..442fee4a1 100644 --- a/include/sys/zil.h +++ b/include/sys/zil.h @@ -395,6 +395,7 @@ typedef struct itx { uint8_t itx_sync; /* synchronous transaction */ zil_callback_t itx_callback; /* Called when the itx is persistent */ void *itx_callback_data; /* User data for the callback */ + size_t itx_size; /* allocated itx structure size */ uint64_t itx_oid; /* object id */ lr_t itx_lr; /* common part of log record */ /* followed by type-specific part of lr_xx_t and its immediate data */ diff --git a/module/zfs/zil.c b/module/zfs/zil.c index d43b26937..9f4312a5a 100644 --- a/module/zfs/zil.c +++ b/module/zfs/zil.c @@ -1254,17 +1254,20 @@ cont: itx_t * zil_itx_create(uint64_t txtype, size_t lrsize) { + size_t itxsize; itx_t *itx; lrsize = P2ROUNDUP_TYPED(lrsize, sizeof (uint64_t), size_t); + itxsize = offsetof(itx_t, itx_lr) + lrsize; - itx = zio_data_buf_alloc(offsetof(itx_t, itx_lr) + lrsize); + itx = zio_data_buf_alloc(itxsize); itx->itx_lr.lrc_txtype = txtype; itx->itx_lr.lrc_reclen = lrsize; itx->itx_lr.lrc_seq = 0; /* defensive */ itx->itx_sync = B_TRUE; /* default is synchronous */ itx->itx_callback = NULL; itx->itx_callback_data = NULL; + itx->itx_size = itxsize; return (itx); } @@ -1272,7 +1275,7 @@ zil_itx_create(uint64_t txtype, size_t lrsize) void zil_itx_destroy(itx_t *itx) { - zio_data_buf_free(itx, offsetof(itx_t, itx_lr)+itx->itx_lr.lrc_reclen); + zio_data_buf_free(itx, itx->itx_size); } /* |