diff options
| author | Josh Law <objecting@objecting.org> | 2026-03-12 19:11:43 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-03-19 16:08:44 +0100 |
| commit | 6e736a18cfbd518514c6fb82f2a46082bffd6394 (patch) | |
| tree | daf2ff756a1ff5c73151a9df7e00ff8f20c7a195 | |
| parent | 12d2b443b8606050fe43c85b7ac55ee4865cb883 (diff) | |
lib/bootconfig: fix snprintf truncation check in xbc_node_compose_key_after()
commit 1120a36bb1e9b9e22de75ecb4ef0b998f73a97f1 upstream.
snprintf() returns the number of characters that would have been
written excluding the NUL terminator. Output is truncated when the
return value is >= the buffer size, not just > the buffer size.
When ret == size, the current code takes the non-truncated path,
advancing buf by ret and reducing size to 0. This is wrong because
the output was actually truncated (the last character was replaced by
NUL). Fix by using >= so the truncation path is taken correctly.
Link: https://lore.kernel.org/all/20260312191143.28719-4-objecting@objecting.org/
Fixes: 76db5a27a827 ("bootconfig: Add Extra Boot Config support")
Cc: stable@vger.kernel.org
Signed-off-by: Josh Law <objecting@objecting.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | lib/bootconfig.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/lib/bootconfig.c b/lib/bootconfig.c index a22e51545fe3..31ac39aeac77 100644 --- a/lib/bootconfig.c +++ b/lib/bootconfig.c @@ -316,7 +316,7 @@ int __init xbc_node_compose_key_after(struct xbc_node *root, depth ? "." : ""); if (ret < 0) return ret; - if (ret > size) { + if (ret >= size) { size = 0; } else { size -= ret; |