diff mbox series

[net-next,v6,4/8] net: pktgen: fix mpls maximum labels list parsing

Message ID 20250221215246.383373-5-ps.report@gmx.net (mailing list archive)
State New
Delegated to: Netdev Maintainers
Headers show
Series Some pktgen fixes/improvments (part II) | expand

Commit Message

Peter Seiderer Feb. 21, 2025, 9:52 p.m. UTC 
Fix mpls maximum labels list parsing up to MAX_MPLS_LABELS/16 entries
(instead of up to MAX_MPLS_LABELS - 1).

Addresses the following:

	$ echo "mpls 00000f00,00000f01,00000f02,00000f03,00000f04,00000f05,00000f06,00000f07,00000f08,00000f09,00000f0a,00000f0b,00000f0c,00000f0d,00000f0e,00000f0f" > /proc/net/pktgen/lo\@0
	-bash: echo: write error: Argument list too long

Signed-off-by: Peter Seiderer <ps.report@gmx.net>
Reviewed-by: Simon Horman <horms@kernel.org>
---
Changes v5 -> v6
  - adjust to dropped patch ''net: pktgen: use defines for the various
    dec/hex number parsing digits lengths'
  - add rev-by Simon Horman

Changes v4 -> v5
  - split up patchset into part i/ii (suggested by Simon Horman)
  - change patch description ('Fixes:' -> 'Addresses the following:',
    suggested by Simon Horman)

Changes v3 -> v4
  - new patch (factored out of patch 'net: pktgen: fix access outside of user
    given buffer in pktgen_if_write()')
---
 net/core/pktgen.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index 204f93de03aa..03ea6b5db156 100644
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -902,6 +902,10 @@  static ssize_t get_labels(const char __user *buffer, struct pktgen_dev *pkt_dev)
 	pkt_dev->nr_labels = 0;
 	do {
 		__u32 tmp;
+
+		if (n >= MAX_MPLS_LABELS)
+			return -E2BIG;
+
 		len = hex32_arg(&buffer[i], 8, &tmp);
 		if (len <= 0)
 			return len;
@@ -913,8 +917,6 @@  static ssize_t get_labels(const char __user *buffer, struct pktgen_dev *pkt_dev)
 			return -EFAULT;
 		i++;
 		n++;
-		if (n >= MAX_MPLS_LABELS)
-			return -E2BIG;
 	} while (c == ',');
 
 	pkt_dev->nr_labels = n;