From 296a4a369bc1078a694f88570972330985b3b1b8 Mon Sep 17 00:00:00 2001 From: Chunwei Chen Date: Fri, 19 Mar 2021 22:53:31 -0700 Subject: Fix zfs_get_data access to files with wrong generation If TX_WRITE is create on a file, and the file is later deleted and a new directory is created on the same object id, it is possible that when zil_commit happens, zfs_get_data will be called on the new directory. This may result in panic as it tries to do range lock. This patch fixes this issue by record the generation number during zfs_log_write, so zfs_get_data can check if the object is valid. Reviewed-by: Brian Behlendorf Signed-off-by: Chunwei Chen Closes #10593 Closes #11682 --- module/zfs/zfs_log.c | 5 +++++ module/zfs/zfs_vnops.c | 14 +++++++++++++- module/zfs/zil.c | 3 ++- module/zfs/zvol.c | 3 ++- 4 files changed, 22 insertions(+), 3 deletions(-) (limited to 'module') diff --git a/module/zfs/zfs_log.c b/module/zfs/zfs_log.c index 4bb529f78..30d5c4821 100644 --- a/module/zfs/zfs_log.c +++ b/module/zfs/zfs_log.c @@ -540,6 +540,7 @@ zfs_log_write(zilog_t *zilog, dmu_tx_t *tx, int txtype, uint32_t blocksize = zp->z_blksz; itx_wr_state_t write_state; uintptr_t fsync_cnt; + uint64_t gen = 0; if (zil_replaying(zilog, tx) || zp->z_unlinked || zfs_xattr_owner_unlinked(zp)) { @@ -562,6 +563,9 @@ zfs_log_write(zilog_t *zilog, dmu_tx_t *tx, int txtype, (void) tsd_set(zfs_fsyncer_key, (void *)(fsync_cnt - 1)); } + (void) sa_lookup(zp->z_sa_hdl, SA_ZPL_GEN(ZTOZSB(zp)), &gen, + sizeof (gen)); + while (resid) { itx_t *itx; lr_write_t *lr; @@ -609,6 +613,7 @@ zfs_log_write(zilog_t *zilog, dmu_tx_t *tx, int txtype, BP_ZERO(&lr->lr_blkptr); itx->itx_private = ZTOZSB(zp); + itx->itx_gen = gen; if (!(ioflag & (O_SYNC | O_DSYNC)) && (zp->z_sync_cnt == 0) && (fsync_cnt == 0)) diff --git a/module/zfs/zfs_vnops.c b/module/zfs/zfs_vnops.c index 0af03e923..8229bc9a9 100644 --- a/module/zfs/zfs_vnops.c +++ b/module/zfs/zfs_vnops.c @@ -740,7 +740,8 @@ static void zfs_get_done(zgd_t *zgd, int error); * Get data to generate a TX_WRITE intent log record. */ int -zfs_get_data(void *arg, lr_write_t *lr, char *buf, struct lwb *lwb, zio_t *zio) +zfs_get_data(void *arg, uint64_t gen, lr_write_t *lr, char *buf, + struct lwb *lwb, zio_t *zio) { zfsvfs_t *zfsvfs = arg; objset_t *os = zfsvfs->z_os; @@ -751,6 +752,7 @@ zfs_get_data(void *arg, lr_write_t *lr, char *buf, struct lwb *lwb, zio_t *zio) dmu_buf_t *db; zgd_t *zgd; int error = 0; + uint64_t zp_gen; ASSERT3P(lwb, !=, NULL); ASSERT3P(zio, !=, NULL); @@ -769,6 +771,16 @@ zfs_get_data(void *arg, lr_write_t *lr, char *buf, struct lwb *lwb, zio_t *zio) zfs_zrele_async(zp); return (SET_ERROR(ENOENT)); } + /* check if generation number matches */ + if (sa_lookup(zp->z_sa_hdl, SA_ZPL_GEN(zfsvfs), &zp_gen, + sizeof (zp_gen)) != 0) { + zfs_zrele_async(zp); + return (SET_ERROR(EIO)); + } + if (zp_gen != gen) { + zfs_zrele_async(zp); + return (SET_ERROR(ENOENT)); + } zgd = (zgd_t *)kmem_zalloc(sizeof (zgd_t), KM_SLEEP); zgd->zgd_lwb = lwb; diff --git a/module/zfs/zil.c b/module/zfs/zil.c index 7b52f9249..d9c304208 100644 --- a/module/zfs/zil.c +++ b/module/zfs/zil.c @@ -1744,7 +1744,8 @@ cont: * completed after "lwb_write_zio" completed. */ error = zilog->zl_get_data(itx->itx_private, - lrwb, dbuf, lwb, lwb->lwb_write_zio); + itx->itx_gen, lrwb, dbuf, lwb, + lwb->lwb_write_zio); if (error == EIO) { txg_wait_synced(zilog->zl_dmu_pool, txg); diff --git a/module/zfs/zvol.c b/module/zfs/zvol.c index 44f9832ce..b6609363f 100644 --- a/module/zfs/zvol.c +++ b/module/zfs/zvol.c @@ -673,7 +673,8 @@ zvol_get_done(zgd_t *zgd, int error) * Get data to generate a TX_WRITE intent log record. */ int -zvol_get_data(void *arg, lr_write_t *lr, char *buf, struct lwb *lwb, zio_t *zio) +zvol_get_data(void *arg, uint64_t arg2, lr_write_t *lr, char *buf, + struct lwb *lwb, zio_t *zio) { zvol_state_t *zv = arg; uint64_t offset = lr->lr_offset; -- cgit v1.2.3