From 5b29891f91dfb8758baf1e2217bef4b16b2b165b 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 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 --- fs/smb/client/fs_context.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/smb/client/fs_context.c b/fs/smb/client/fs_context.c index 5f3c5967a0f5..c983021c406b 100644 --- a/fs/smb/client/fs_context.c +++ b/fs/smb/client/fs_context.c @@ -1351,11 +1351,11 @@ 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) {