diff mbox series

[v2,5/6] cio: ensure the copied buf is NUL terminated

Message ID 20240424-fix-oob-read-v2-5-f1f1b53a10f4@gmail.com (mailing list archive)
State Not Applicable
Headers show
Series Ensure the copied buf is NUL terminated | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Guessed tree name to be net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 8 this patch: 8
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 8 of 8 maintainers
netdev/build_clang success Errors and warnings before: 8 this patch: 8
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success Fixes tag looks correct
netdev/build_allmodconfig_warn success Errors and warnings before: 8 this patch: 8
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 8 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 1 this patch: 1
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-04-25--09-00 (tests: 995)

Commit Message

Bui Quang Minh April 24, 2024, 2:44 p.m. UTC
Currently, we allocate a lbuf-sized kernel buffer and copy lbuf from
userspace to that buffer. Later, we use scanf on this buffer but we don't
ensure that the string is terminated inside the buffer, this can lead to
OOB read when using scanf. Fix this issue by using memdup_user_nul instead.

Fixes: a4f17cc72671 ("s390/cio: add CRW inject functionality")
Signed-off-by: Bui Quang Minh <minhquangbui99@gmail.com>
---
 drivers/s390/cio/cio_inject.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Heiko Carstens April 24, 2024, 2:54 p.m. UTC | #1
On Wed, Apr 24, 2024 at 09:44:22PM +0700, Bui Quang Minh wrote:
> Currently, we allocate a lbuf-sized kernel buffer and copy lbuf from
> userspace to that buffer. Later, we use scanf on this buffer but we don't
> ensure that the string is terminated inside the buffer, this can lead to
> OOB read when using scanf. Fix this issue by using memdup_user_nul instead.
> 
> Fixes: a4f17cc72671 ("s390/cio: add CRW inject functionality")
> Signed-off-by: Bui Quang Minh <minhquangbui99@gmail.com>
> ---
>  drivers/s390/cio/cio_inject.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Alexander Gordeev April 24, 2024, 3:16 p.m. UTC | #2
On Wed, Apr 24, 2024 at 09:44:22PM +0700, Bui Quang Minh wrote:
> Currently, we allocate a lbuf-sized kernel buffer and copy lbuf from
> userspace to that buffer. Later, we use scanf on this buffer but we don't
> ensure that the string is terminated inside the buffer, this can lead to
> OOB read when using scanf. Fix this issue by using memdup_user_nul instead.
> 
> Fixes: a4f17cc72671 ("s390/cio: add CRW inject functionality")
> Signed-off-by: Bui Quang Minh <minhquangbui99@gmail.com>
> ---
>  drivers/s390/cio/cio_inject.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Applied, thanks!
Alexander Gordeev April 26, 2024, 10:10 a.m. UTC | #3
On Wed, Apr 24, 2024 at 05:16:56PM +0200, Alexander Gordeev wrote:
> Applied, thanks!

Hi Jakub,

I just want to make sure you do not have plans to pull this patch
via the net tree, right? (I schedulled it for the s390 tree already).

Thanks!
Jakub Kicinski April 26, 2024, 2:29 p.m. UTC | #4
On Fri, 26 Apr 2024 12:10:35 +0200 Alexander Gordeev wrote:
> On Wed, Apr 24, 2024 at 05:16:56PM +0200, Alexander Gordeev wrote:
> > Applied, thanks!  
> 
> Hi Jakub,
> 
> I just want to make sure you do not have plans to pull this patch
> via the net tree, right? (I schedulled it for the s390 tree already).

Yes, go for it. I picked 1, 2 and 6, no interest in the other 3 :)
diff mbox series

Patch

diff --git a/drivers/s390/cio/cio_inject.c b/drivers/s390/cio/cio_inject.c
index 8613fa937237..a2e771ebae8e 100644
--- a/drivers/s390/cio/cio_inject.c
+++ b/drivers/s390/cio/cio_inject.c
@@ -95,7 +95,7 @@  static ssize_t crw_inject_write(struct file *file, const char __user *buf,
 		return -EINVAL;
 	}
 
-	buffer = vmemdup_user(buf, lbuf);
+	buffer = memdup_user_nul(buf, lbuf);
 	if (IS_ERR(buffer))
 		return -ENOMEM;