Honour the user given buffer size for the strn_len() calls (otherwise strn_len() will access memory outside of the user given buffer).
Signed-off-by: Peter Seiderer ps.report@gmx.net Reviewed-by: Simon Horman horms@kernel.org --- Changes v4 -> v5 - split up patchset into part i/ii (suggested by Simon Horman)
Changes v3 -> v4 - add rev-by Simon Horman
Changes v2 -> v3: - no changes
Changes v1 -> v2: - no changes --- net/core/pktgen.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/net/core/pktgen.c b/net/core/pktgen.c index f6e35ba035c7..55064713223e 100644 --- a/net/core/pktgen.c +++ b/net/core/pktgen.c @@ -1900,8 +1900,8 @@ static ssize_t pktgen_thread_write(struct file *file, i = len;
/* Read variable name */ - - len = strn_len(&user_buffer[i], sizeof(name) - 1); + max = min(sizeof(name) - 1, count - i); + len = strn_len(&user_buffer[i], max); if (len < 0) return len;
@@ -1931,7 +1931,8 @@ static ssize_t pktgen_thread_write(struct file *file, if (!strcmp(name, "add_device")) { char f[32]; memset(f, 0, 32); - len = strn_len(&user_buffer[i], sizeof(f) - 1); + max = min(sizeof(f) - 1, count - i); + len = strn_len(&user_buffer[i], max); if (len < 0) { ret = len; goto out;