lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Mon, 11 Apr 2022 20:43:35 -0400 From: Sasha Levin <sashal@...nel.org> To: linux-kernel@...r.kernel.org, stable@...r.kernel.org Cc: Xiaoguang Wang <xiaoguang.wang@...ux.alibaba.com>, Bodo Stroesser <bostroesser@...il.com>, "Martin K . Petersen" <martin.petersen@...cle.com>, Sasha Levin <sashal@...nel.org>, linux-scsi@...r.kernel.org, target-devel@...r.kernel.org Subject: [PATCH AUTOSEL 5.17 17/49] scsi: target: tcmu: Fix possible page UAF From: Xiaoguang Wang <xiaoguang.wang@...ux.alibaba.com> [ Upstream commit a6968f7a367f128d120447360734344d5a3d5336 ] tcmu_try_get_data_page() looks up pages under cmdr_lock, but it does not take refcount properly and just returns page pointer. When tcmu_try_get_data_page() returns, the returned page may have been freed by tcmu_blocks_release(). We need to get_page() under cmdr_lock to avoid concurrent tcmu_blocks_release(). Link: https://lore.kernel.org/r/20220311132206.24515-1-xiaoguang.wang@linux.alibaba.com Reviewed-by: Bodo Stroesser <bostroesser@...il.com> Signed-off-by: Xiaoguang Wang <xiaoguang.wang@...ux.alibaba.com> Signed-off-by: Martin K. Petersen <martin.petersen@...cle.com> Signed-off-by: Sasha Levin <sashal@...nel.org> --- drivers/target/target_core_user.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c index 7b2a89a67cdb..06a5c4086551 100644 --- a/drivers/target/target_core_user.c +++ b/drivers/target/target_core_user.c @@ -1820,6 +1820,7 @@ static struct page *tcmu_try_get_data_page(struct tcmu_dev *udev, uint32_t dpi) mutex_lock(&udev->cmdr_lock); page = xa_load(&udev->data_pages, dpi); if (likely(page)) { + get_page(page); mutex_unlock(&udev->cmdr_lock); return page; } @@ -1876,6 +1877,7 @@ static vm_fault_t tcmu_vma_fault(struct vm_fault *vmf) /* For the vmalloc()ed cmd area pages */ addr = (void *)(unsigned long)info->mem[mi].addr + offset; page = vmalloc_to_page(addr); + get_page(page); } else { uint32_t dpi; @@ -1886,7 +1888,6 @@ static vm_fault_t tcmu_vma_fault(struct vm_fault *vmf) return VM_FAULT_SIGBUS; } - get_page(page); vmf->page = page; return 0; } -- 2.35.1
Powered by blists - more mailing lists