From: Murad Masimov <m.masimov@mt-integration.ru> stable inclusion from stable-v6.6.84 commit 9e438d0410a4002d24f420f2c28897ba2dc0af64 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBY44A CVE: CVE-2025-21963 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ 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 <m.masimov@mt-integration.ru> Signed-off-by: Steve French <stfrench@microsoft.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Li Lingfeng <lilingfeng3@huawei.com> --- 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 695a2a223f93..b3fb1db26eb3 100644 --- a/fs/smb/client/fs_context.c +++ b/fs/smb/client/fs_context.c @@ -1269,11 +1269,11 @@ 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) { -- 2.31.1