diff mbox series

[net] gtp: fix a potential NULL pointer dereference

Message ID 20240825191638.146748-1-xiyou.wangcong@gmail.com (mailing list archive)
State Accepted
Commit defd8b3c37b0f9cb3e0f60f47d3d78d459d57fda
Delegated to: Netdev Maintainers
Headers show
Series [net] gtp: fix a potential NULL pointer dereference | expand

Checks

Context Check Description
netdev/series_format success Single patches do not need cover letters
netdev/tree_selection success Clearly marked for net
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag present in non-next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 16 this patch: 16
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 4 maintainers not CCed: pabeni@redhat.com osmocom-net-gprs@lists.osmocom.org kuba@kernel.org edumazet@google.com
netdev/build_clang success Errors and warnings before: 16 this patch: 16
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: 16 this patch: 16
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: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-08-25--21-00 (tests: 714)

Commit Message

Cong Wang Aug. 25, 2024, 7:16 p.m. UTC 
From: Cong Wang <cong.wang@bytedance.com>

When sockfd_lookup() fails, gtp_encap_enable_socket() returns a
NULL pointer, but its callers only check for error pointers thus miss
the NULL pointer case.

Fix it by returning an error pointer with the error code carried from
sockfd_lookup().

(I found this bug during code inspection.)

Fixes: 1e3a3abd8b28 ("gtp: make GTP sockets in gtp_newlink optional")
Cc: Andreas Schultz <aschultz@tpip.net>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Harald Welte <laforge@gnumonks.org>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
---
 drivers/net/gtp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Simon Horman Aug. 27, 2024, 2:41 p.m. UTC | #1 
On Sun, Aug 25, 2024 at 12:16:38PM -0700, Cong Wang wrote:
> From: Cong Wang <cong.wang@bytedance.com>
> 
> When sockfd_lookup() fails, gtp_encap_enable_socket() returns a
> NULL pointer, but its callers only check for error pointers thus miss
> the NULL pointer case.
> 
> Fix it by returning an error pointer with the error code carried from
> sockfd_lookup().
> 
> (I found this bug during code inspection.)
> 
> Fixes: 1e3a3abd8b28 ("gtp: make GTP sockets in gtp_newlink optional")
> Cc: Andreas Schultz <aschultz@tpip.net>
> Cc: Pablo Neira Ayuso <pablo@netfilter.org>
> Cc: Harald Welte <laforge@gnumonks.org>
> Signed-off-by: Cong Wang <cong.wang@bytedance.com>

Thanks Cong,

I agree with your analysis.

Reviewed-by: Simon Horman <horms@kernel.org>
Pablo Neira Ayuso Aug. 27, 2024, 4:05 p.m. UTC | #2 
On Sun, Aug 25, 2024 at 12:16:38PM -0700, Cong Wang wrote:
> From: Cong Wang <cong.wang@bytedance.com>
> 
> When sockfd_lookup() fails, gtp_encap_enable_socket() returns a
> NULL pointer, but its callers only check for error pointers thus miss
> the NULL pointer case.
> 
> Fix it by returning an error pointer with the error code carried from
> sockfd_lookup().
> 
> (I found this bug during code inspection.)
> 
> Fixes: 1e3a3abd8b28 ("gtp: make GTP sockets in gtp_newlink optional")
> Cc: Andreas Schultz <aschultz@tpip.net>
> Cc: Pablo Neira Ayuso <pablo@netfilter.org>
> Cc: Harald Welte <laforge@gnumonks.org>
> Signed-off-by: Cong Wang <cong.wang@bytedance.com>

Reviewed-by: Pablo Neira Ayuso <pablo@netfilter.org>

Thanks.
patchwork-bot+netdevbpf@kernel.org Aug. 27, 2024, 9:30 p.m. UTC | #3 
Hello:

This patch was applied to netdev/net.git (main)
by Jakub Kicinski <kuba@kernel.org>:

On Sun, 25 Aug 2024 12:16:38 -0700 you wrote:
> From: Cong Wang <cong.wang@bytedance.com>
> 
> When sockfd_lookup() fails, gtp_encap_enable_socket() returns a
> NULL pointer, but its callers only check for error pointers thus miss
> the NULL pointer case.
> 
> Fix it by returning an error pointer with the error code carried from
> sockfd_lookup().
> 
> [...]

Here is the summary with links:
  - [net] gtp: fix a potential NULL pointer dereference
    https://git.kernel.org/netdev/net/c/defd8b3c37b0

You are awesome, thank you!
diff mbox series

Patch

diff --git a/drivers/net/gtp.c b/drivers/net/gtp.c
index 0696faf60013..2e94d10348cc 100644
--- a/drivers/net/gtp.c
+++ b/drivers/net/gtp.c
@@ -1653,7 +1653,7 @@  static struct sock *gtp_encap_enable_socket(int fd, int type,
 	sock = sockfd_lookup(fd, &err);
 	if (!sock) {
 		pr_debug("gtp socket fd=%d not found\n", fd);
-		return NULL;
+		return ERR_PTR(err);
 	}
 
 	sk = sock->sk;