This is a note to let you know that I've just added the patch titled jfs: Use unsigned variable for length calculations to the 6.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: jfs-use-unsigned-variable-for-length-calculations.patch and it can be found in the queue-6.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 0ee0e10fe74f1a814ef4d2084c80be1338312dc5 Author: Kees Cook <keescook@xxxxxxxxxxxx> Date: Sat Feb 4 10:33:56 2023 -0800 jfs: Use unsigned variable for length calculations [ Upstream commit 820eb59da8c7ca7e705a02f37dda2be316807847 ] To avoid confusing the compiler about possible negative sizes, switch "ssize" which can never be negative from int to u32. Seen with GCC 13: ../fs/jfs/namei.c: In function 'jfs_symlink': ../include/linux/fortify-string.h:57:33: warning: '__builtin_memcpy' pointer overflow between offset 0 and size [-2147483648, -1] [-Warray-bounds=] 57 | #define __underlying_memcpy __builtin_memcpy | ^ ... ../fs/jfs/namei.c:950:17: note: in expansion of macro 'memcpy' 950 | memcpy(ip->i_link, name, ssize); | ^~~~~~ Cc: Dave Kleikamp <shaggy@xxxxxxxxxx> Cc: Christian Brauner <brauner@xxxxxxxxxx> Cc: Dave Chinner <dchinner@xxxxxxxxxx> Cc: jfs-discussion@xxxxxxxxxxxxxxxxxxxxx Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> Acked-by: Jeff Xu <jeffxu@xxxxxxxxxxxx> Message-Id: <20230204183355.never.877-kees@xxxxxxxxxx> Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/fs/jfs/namei.c b/fs/jfs/namei.c index b29d68b5eec53..494b9f4043cf6 100644 --- a/fs/jfs/namei.c +++ b/fs/jfs/namei.c @@ -876,7 +876,7 @@ static int jfs_symlink(struct mnt_idmap *idmap, struct inode *dip, tid_t tid; ino_t ino = 0; struct component_name dname; - int ssize; /* source pathname size */ + u32 ssize; /* source pathname size */ struct btstack btstack; struct inode *ip = d_inode(dentry); s64 xlen = 0; @@ -957,7 +957,7 @@ static int jfs_symlink(struct mnt_idmap *idmap, struct inode *dip, if (ssize > sizeof (JFS_IP(ip)->i_inline)) JFS_IP(ip)->mode2 &= ~INLINEEA; - jfs_info("jfs_symlink: fast symlink added ssize:%d name:%s ", + jfs_info("jfs_symlink: fast symlink added ssize:%u name:%s ", ssize, name); } /* @@ -987,7 +987,7 @@ static int jfs_symlink(struct mnt_idmap *idmap, struct inode *dip, ip->i_size = ssize - 1; while (ssize) { /* This is kind of silly since PATH_MAX == 4K */ - int copy_size = min(ssize, PSIZE); + u32 copy_size = min_t(u32, ssize, PSIZE); mp = get_metapage(ip, xaddr, PSIZE, 1);