lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Sat, 4 Feb 2023 20:25:45 +0000 From: "Dr. David Alan Gilbert" <linux@...blig.org> To: Kees Cook <keescook@...omium.org> Cc: Dave Kleikamp <shaggy@...nel.org>, Christian Brauner <brauner@...nel.org>, Dave Chinner <dchinner@...hat.com>, jfs-discussion@...ts.sourceforge.net, linux-kernel@...r.kernel.org, linux-hardening@...r.kernel.org Subject: Re: [PATCH] jfs: Use unsigned variable for length calculations * Kees Cook (keescook@...omium.org) wrote: > 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@...nel.org> > Cc: Christian Brauner <brauner@...nel.org> > Cc: Dave Chinner <dchinner@...hat.com> > Cc: jfs-discussion@...ts.sourceforge.net > Signed-off-by: Kees Cook <keescook@...omium.org> > --- > fs/jfs/namei.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/fs/jfs/namei.c b/fs/jfs/namei.c > index b29d68b5eec5..494b9f4043cf 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 */ Had you considered using size_t - this is set from a strlen and used by a memcpy that both talk size_t. Dave > 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); > > -- > 2.34.1 > -- -----Open up your eyes, open up your mind, open up your code ------- / Dr. David Alan Gilbert | Running GNU/Linux | Happy \ \ dave @ treblig.org | | In Hex / \ _________________________|_____ http://www.treblig.org |_______/
Powered by blists - more mailing lists