From 0c26edf477e093cefc41637f5bccc102e1a77399 Mon Sep 17 00:00:00 2001 From: Murad Masimov Date: Tue, 11 Mar 2025 17:22:04 +0300 Subject: [PATCH] cifs: Fix integer overflow while processing acdirmax mount option [ Upstream commit 5b29891f91dfb8758baf1e2217bef4b16b2b165b ] User-provided mount parameter acdirmax of type u32 is intended to have an upper limit, but before it is validated, the value is converted from seconds to jiffies which can lead to an integer overflow. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: 4c9f948142a5 ("cifs: Add new mount parameter "acdirmax" to allow caching directory metadata") Signed-off-by: Murad Masimov Signed-off-by: Steve French Signed-off-by: Sasha Levin --- fs/cifs/fs_context.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/cifs/fs_context.c b/fs/cifs/fs_context.c index d86cbed997fdd..9b1c0e0dfc63b 100644 --- a/fs/cifs/fs_context.c +++ b/fs/cifs/fs_context.c @@ -1062,11 +1062,11 @@ static int smb3_fs_context_parse_param(struct fs_context *fc, ctx->acregmax = HZ * result.uint_32; break; case Opt_acdirmax: - ctx->acdirmax = HZ * result.uint_32; - if (ctx->acdirmax > CIFS_MAX_ACTIMEO) { + if (result.uint_32 > CIFS_MAX_ACTIMEO / HZ) { cifs_errorf(fc, "acdirmax too large\n"); goto cifs_parse_mount_err; } + ctx->acdirmax = HZ * result.uint_32; break; case Opt_actimeo: if (HZ * result.uint_32 > CIFS_MAX_ACTIMEO) { -- 2.47.3