diff mbox series

[v5,net-next,03/13] net: limit GSO_MAX_SIZE to 524280 bytes

Message ID 20220509222149.1763877-4-eric.dumazet@gmail.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series tcp: BIG TCP implementation | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net-next, async
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 4693 this patch: 4693
netdev/cc_maintainers success CCed 5 of 5 maintainers
netdev/build_clang success Errors and warnings before: 1059 this patch: 1059
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 4844 this patch: 4844
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 19 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Eric Dumazet May 9, 2022, 10:21 p.m. UTC 
From: Eric Dumazet <edumazet@google.com>

Make sure we will not overflow shinfo->gso_segs

Minimal TCP MSS size is 8 bytes, and shinfo->gso_segs
is a 16bit field.

TCP_MIN_GSO_SIZE is currently defined in include/net/tcp.h,
it seems cleaner to not bring tcp details into include/linux/netdevice.h

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 include/linux/netdevice.h | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 9a34cc45b20a4465a9e1532c39f410b26604144f..2ef9254a9d3a57403f510d32194d8be6730b1645 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -2263,12 +2263,17 @@  struct net_device {
 
 	/* for setting kernel sock attribute on TCP connection setup */
 #define GSO_LEGACY_MAX_SIZE	65536u
-#define GSO_MAX_SIZE		UINT_MAX
+#define GSO_MAX_SEGS		65535u
+
+/* TCP minimal MSS is 8 (TCP_MIN_GSO_SIZE),
+ * and shinfo->gso_segs is a 16bit field.
+ */
+#define GSO_MAX_SIZE		(8 * GSO_MAX_SEGS)
+
 	unsigned int		gso_max_size;
 #define TSO_LEGACY_MAX_SIZE	65536
 #define TSO_MAX_SIZE		UINT_MAX
 	unsigned int		tso_max_size;
-#define GSO_MAX_SEGS		65535
 	u16			gso_max_segs;
 #define TSO_MAX_SEGS		U16_MAX
 	u16			tso_max_segs;