c/mirror_zfs
1
0
Fork 0
mirror of https://git.proxmox.com/git/mirror_zfs.git synced 2026-05-24 19:28:53 +03:00
Code Issues Packages Projects Releases Wiki Activity

Fix errant EFAULT during writes (#8719)

Browse Source 
Commit 98bb45e resolved a deadlock which could occur when
handling a page fault in zfs_write().  This change added
the uio_fault_disable field to the uio structure but failed
to initialize it to B_FALSE.  This uninitialized field would
cause uiomove_iov() to call __copy_from_user_inatomic()
instead of copy_from_user() resulting in unexpected EFAULTs.

Resolve the issue by fully initializing the uio, and clearing
the uio_fault_disable flags after it's used in zfs_write().

Additionally, reorder the uio_t field assignments to match
the order the fields are declared in the  structure.

Reviewed-by: Chunwei Chen <tuxoko@gmail.com>
Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #8640 
Closes #8719
This commit is contained in:
Brian Behlendorf
2019-05-08 10:04:04 -07:00
committed by GitHub
parent 1f02ecc5a5
commit 515ddf6504
4 changed files with 16 additions and 16 deletions
Download Patch File Download Diff File Expand all files Collapse all files
module/zfs/zvol.c
+5 -5
View File
@@ -727,12 +727,12 @@ static void
uio_from_bio(uio_t *uio, struct bio *bio)
{
uio->uio_bvec = &bio->bi_io_vec[BIO_BI_IDX(bio)];
uio->uio_skip = BIO_BI_SKIP(bio);
uio->uio_resid = BIO_BI_SIZE(bio);
uio->uio_iovcnt = bio->bi_vcnt - BIO_BI_IDX(bio);
uio->uio_loffset = BIO_BI_SECTOR(bio) << 9;
uio->uio_limit = MAXOFFSET_T;
uio->uio_segflg = UIO_BVEC;
uio->uio_limit = MAXOFFSET_T;
uio->uio_resid = BIO_BI_SIZE(bio);
uio->uio_skip = BIO_BI_SKIP(bio);
}
static void
@@ -742,7 +742,7 @@ zvol_write(void *arg)
zv_request_t *zvr = arg;
struct bio *bio = zvr->bio;
uio_t uio;
uio_t uio = { { 0 }, 0 };
uio_from_bio(&uio, bio);
zvol_state_t *zv = zvr->zv;
@@ -897,7 +897,7 @@ zvol_read(void *arg)
zv_request_t *zvr = arg;
struct bio *bio = zvr->bio;
uio_t uio;
uio_t uio = { { 0 }, 0 };
uio_from_bio(&uio, bio);
zvol_state_t *zv = zvr->zv;