[PATCH net-next v6 4/8] net: pktgen: fix mpls maximum labels list parsing
From: Peter Seiderer
Date: Fri Feb 21 2025 - 16:53:23 EST
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@xxxxxxx>
Reviewed-by: Simon Horman <horms@xxxxxxxxxx>
---
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 --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;
--
2.48.1