From 38da0f49e8aa1649af397d53f88e163d0e60c058 Mon Sep 17 00:00:00 2001 From: Akinobu Mita Date: Mon, 13 Apr 2015 23:21:56 +0900 Subject: [PATCH] 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 Cc: Sagi Grimberg Cc: "Martin K. Petersen" Cc: Christoph Hellwig Cc: "James E.J. Bottomley" Cc: # v3.14+ Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_file.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) diff --git a/drivers/target/target_core_file.c b/drivers/target/target_core_file.c index fa54835f398b..3dcfc73528ec 100644 --- a/drivers/target/target_core_file.c +++ b/drivers/target/target_core_file.c @@ -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; }