From: Jan Beulich Date: Wed, 12 Mar 2025 15:32:45 +0000 (+0100) Subject: xenfs/xensyms: respect hypervisor's "next" indication X-Git-Tag: v5.10.237~228 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=9d33538f7c28dbf77afa9f8b3a4d92656ab098f2;p=thirdparty%2Fkernel%2Fstable.git xenfs/xensyms: respect hypervisor's "next" indication commit 5c4e79e29a9fe4ea132118ac40c2bc97cfe23077 upstream. The interface specifies the symnum field as an input and output; the hypervisor sets it to the next sequential symbol's index. xensyms_next() incrementing the position explicitly (and xensyms_next_sym() decrementing it to "rewind") is only correct as long as the sequence of symbol indexes is non-sparse. Use the hypervisor-supplied value instead to update the position in xensyms_next(), and use the saved incoming index in xensyms_next_sym(). Cc: stable@kernel.org Fixes: a11f4f0a4e18 ("xen: xensyms support") Signed-off-by: Jan Beulich Reviewed-by: Juergen Gross Message-ID: <15d5e7fa-ec5d-422f-9319-d28bed916349@suse.com> Signed-off-by: Juergen Gross Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/xen/xenfs/xensyms.c b/drivers/xen/xenfs/xensyms.c index c6c73a33c44d5..18bc11756ad3b 100644 --- a/drivers/xen/xenfs/xensyms.c +++ b/drivers/xen/xenfs/xensyms.c @@ -48,7 +48,7 @@ static int xensyms_next_sym(struct xensyms *xs) return -ENOMEM; set_xen_guest_handle(symdata->name, xs->name); - symdata->symnum--; /* Rewind */ + symdata->symnum = symnum; /* Rewind */ ret = HYPERVISOR_platform_op(&xs->op); if (ret < 0) @@ -78,7 +78,7 @@ static void *xensyms_next(struct seq_file *m, void *p, loff_t *pos) { struct xensyms *xs = (struct xensyms *)m->private; - xs->op.u.symdata.symnum = ++(*pos); + *pos = xs->op.u.symdata.symnum; if (xensyms_next_sym(xs)) return NULL;