Hi Kent, Did you see this?
Best regards On Friday, November 1st, 2024 at 12:22 AM, Piotr Zalewski <[email protected]> wrote: > Use opt->max-1 in bch2_opt_validate when option type is BCH_OPT_STR. When > > option type is BCH_OPT_STR, real option's max is one less than the max > value stored in option structure. > > Reported-by: [email protected] > Closes: https://syzkaller.appspot.com/bug?extid=bee87a0c3291c06aa8c6 > Fixes: 63c4b2545382 ("bcachefs: Better superblock opt validation") > Signed-off-by: Piotr Zalewski [email protected] > > --- > fs/bcachefs/opts.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/fs/bcachefs/opts.c b/fs/bcachefs/opts.c > index 83f55cf99d46..bffcbe6a6fd0 100644 > --- a/fs/bcachefs/opts.c > +++ b/fs/bcachefs/opts.c > @@ -290,6 +290,8 @@ static int bch2_mount_opt_lookup(const char *name) > > int bch2_opt_validate(const struct bch_option *opt, u64 v, struct printbuf > *err) > { > + const u64 opt_max = opt->type == BCH_OPT_STR ? opt->max - 1 : opt->max; > > + > if (v < opt->min) { > > if (err) > prt_printf(err, "%s: too small (min %llu)", > @@ -297,10 +299,10 @@ int bch2_opt_validate(const struct bch_option *opt, u64 > v, struct printbuf *err) > return -BCH_ERR_ERANGE_option_too_small; > } > > - if (opt->max && v >= opt->max) { > > + if (opt->max && v >= opt_max) { > > if (err) > prt_printf(err, "%s: too big (max %llu)", > - opt->attr.name, opt->max); > > + opt->attr.name, opt_max); > > return -BCH_ERR_ERANGE_option_too_big; > } > > -- > 2.47.0 >
