From: Murad Masimov Date: Tue, 11 Mar 2025 14:22:04 +0000 (+0300) Subject: cifs: Fix integer overflow while processing acdirmax mount option X-Git-Tag: v6.14-rc7~9^2~3 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=5b29891f91dfb8758baf1e2217bef4b16b2b165b;p=thirdparty%2Flinux.git 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 --- diff --git a/fs/smb/client/fs_context.c b/fs/smb/client/fs_context.c index 5f3c5967a0f5a..c983021c406bb 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) {