target/file: Fix BUG() when CONFIG_DEBUG_SG=y and DIF protection enabled

When CONFIG_DEBUG_SG=y and DIF protection support enabled, kernel
BUG()s are triggered due to the following two issues:

1) prot_sg is not initialized by sg_init_table().

When CONFIG_DEBUG_SG=y, scatterlist helpers check sg entry has a
correct magic value.

2) vmalloc'ed buffer is passed to sg_set_buf().

sg_set_buf() uses virt_to_page() to convert virtual address to struct
page, but it doesn't work with vmalloc address.  vmalloc_to_page()
should be used instead.  As prot_buf isn't usually too large, so
fix it by allocating prot_buf by kmalloc instead of vmalloc.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: <stable@vger.kernel.org> # v3.14+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This commit is contained in:
Akinobu Mita 2015-04-13 23:21:56 +09:00 committed by Nicholas Bellinger
parent dc0fafdab8
commit 38da0f49e8

View file

@ -274,7 +274,7 @@ static int fd_do_prot_rw(struct se_cmd *cmd, struct fd_prot *fd_prot,
se_dev->prot_length;
if (!is_write) {
fd_prot->prot_buf = vzalloc(prot_size);
fd_prot->prot_buf = kzalloc(prot_size, GFP_KERNEL);
if (!fd_prot->prot_buf) {
pr_err("Unable to allocate fd_prot->prot_buf\n");
return -ENOMEM;
@ -286,9 +286,10 @@ static int fd_do_prot_rw(struct se_cmd *cmd, struct fd_prot *fd_prot,
fd_prot->prot_sg_nents, GFP_KERNEL);
if (!fd_prot->prot_sg) {
pr_err("Unable to allocate fd_prot->prot_sg\n");
vfree(fd_prot->prot_buf);
kfree(fd_prot->prot_buf);
return -ENOMEM;
}
sg_init_table(fd_prot->prot_sg, fd_prot->prot_sg_nents);
size = prot_size;
for_each_sg(fd_prot->prot_sg, sg, fd_prot->prot_sg_nents, i) {
@ -318,7 +319,7 @@ static int fd_do_prot_rw(struct se_cmd *cmd, struct fd_prot *fd_prot,
if (is_write || ret < 0) {
kfree(fd_prot->prot_sg);
vfree(fd_prot->prot_buf);
kfree(fd_prot->prot_buf);
}
return ret;
@ -599,11 +600,11 @@ fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
0, fd_prot.prot_sg, 0);
if (rc) {
kfree(fd_prot.prot_sg);
vfree(fd_prot.prot_buf);
kfree(fd_prot.prot_buf);
return rc;
}
kfree(fd_prot.prot_sg);
vfree(fd_prot.prot_buf);
kfree(fd_prot.prot_buf);
}
} else {
memset(&fd_prot, 0, sizeof(struct fd_prot));
@ -619,7 +620,7 @@ fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
0, fd_prot.prot_sg, 0);
if (rc) {
kfree(fd_prot.prot_sg);
vfree(fd_prot.prot_buf);
kfree(fd_prot.prot_buf);
return rc;
}
}
@ -655,7 +656,7 @@ fd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
if (ret < 0) {
kfree(fd_prot.prot_sg);
vfree(fd_prot.prot_buf);
kfree(fd_prot.prot_buf);
return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
}