From 78004e9a87f240df03e2f73120d291763c32e0a7 Mon Sep 17 00:00:00 2001 From: Ali Ahmet Memis Date: Fri, 21 Aug 2026 01:45:27 +0000 Subject: openrisc: fix arbitrary kernel memory access via or1k_atomic syscall sys_or1k_atomic() (syscall 244 in the "or1k" ABI) takes two user pointers, v1 and v2, and swaps the words they point to in hand-written assembly. l.lwz r29,0(r4) l.lwz r27,0(r5) l.sw 0(r4),r27 l.sw 0(r5),r29 The pointers are not checked with access_ok(). The four memory accesses also have no exception table entries. A caller passes a kernel address as either pointer, and the syscall reads from and writes to it directly. This gives an unprivileged process a kernel read/write primitive. It overwrites kernel data such as the sys_call_table, gaining code execution in kernel context. Check both pointers before entering the critical section. Add fixups for the four memory accesses so faults on valid but unmapped user addresses return -EFAULT. [shorne@gmail.com: fix comment style] Fixes: 9d02a4283e9c ("OpenRISC: Boot code") Cc: stable@vger.kernel.org Signed-off-by: Ali Ahmet Memis Signed-off-by: Stafford Horne --- security/selinux/genheaders.c | 154 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 154 insertions(+) create mode 100644 security/selinux/genheaders.c (limited to 'security/selinux/genheaders.c') diff --git a/security/selinux/genheaders.c b/security/selinux/genheaders.c new file mode 100644 index 000000000..3834d7eb0 --- /dev/null +++ b/security/selinux/genheaders.c @@ -0,0 +1,154 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include +#include +#include +#include +#include +#include + +struct security_class_mapping { + const char *name; + const char *perms[sizeof(unsigned) * 8 + 1]; +}; + +#include "classmap.h" +#include "initial_sid_to_string.h" + +const char *progname; + +static void usage(void) +{ + printf("usage: %s flask.h av_permissions.h\n", progname); + exit(1); +} + +static char *stoupperx(const char *s) +{ + char *s2 = strdup(s); + char *p; + + if (!s2) { + fprintf(stderr, "%s: out of memory\n", progname); + exit(3); + } + + for (p = s2; *p; p++) + *p = toupper(*p); + return s2; +} + +int main(int argc, char *argv[]) +{ + int i, j; + int isids_len; + FILE *fout; + + progname = argv[0]; + + if (argc < 3) + usage(); + + fout = fopen(argv[1], "w"); + if (!fout) { + fprintf(stderr, "Could not open %s for writing: %s\n", + argv[1], strerror(errno)); + exit(2); + } + + fprintf(fout, "/* This file is automatically generated. Do not edit. */\n"); + fprintf(fout, "#ifndef _SELINUX_FLASK_H_\n#define _SELINUX_FLASK_H_\n\n"); + + for (i = 0; secclass_map[i].name; i++) { + char *name = stoupperx(secclass_map[i].name); + + fprintf(fout, "#define SECCLASS_%-39s %2d\n", name, i+1); + free(name); + } + + fprintf(fout, "\n"); + + isids_len = sizeof(initial_sid_to_string) / sizeof(char *); + for (i = 1; i < isids_len; i++) { + const char *s = initial_sid_to_string[i]; + if (s) { + char *sidname = stoupperx(s); + + fprintf(fout, "#define SECINITSID_%-39s %2d\n", sidname, i); + free(sidname); + } + } + fprintf(fout, "\n#define SECINITSID_NUM %d\n", i-1); + fprintf(fout, "\nstatic inline bool security_is_socket_class(u16 kern_tclass)\n"); + fprintf(fout, "{\n"); + fprintf(fout, "\tbool sock = false;\n\n"); + fprintf(fout, "\tswitch (kern_tclass) {\n"); + for (i = 0; secclass_map[i].name; i++) { + static char s[] = "SOCKET"; + int len, l; + char *name = stoupperx(secclass_map[i].name); + + len = strlen(name); + l = sizeof(s) - 1; + if (len >= l && memcmp(name + len - l, s, l) == 0) + fprintf(fout, "\tcase SECCLASS_%s:\n", name); + free(name); + } + fprintf(fout, "\t\tsock = true;\n"); + fprintf(fout, "\t\tbreak;\n"); + fprintf(fout, "\tdefault:\n"); + fprintf(fout, "\t\tbreak;\n"); + fprintf(fout, "\t}\n\n"); + fprintf(fout, "\treturn sock;\n"); + fprintf(fout, "}\n"); + + fprintf(fout, "\n#endif\n"); + + if (fclose(fout) != 0) { + fprintf(stderr, "Could not successfully close %s: %s\n", + argv[1], strerror(errno)); + exit(4); + } + + fout = fopen(argv[2], "w"); + if (!fout) { + fprintf(stderr, "Could not open %s for writing: %s\n", + argv[2], strerror(errno)); + exit(5); + } + + fprintf(fout, "/* This file is automatically generated. Do not edit. */\n"); + fprintf(fout, "#ifndef _SELINUX_AV_PERMISSIONS_H_\n#define _SELINUX_AV_PERMISSIONS_H_\n\n"); + + for (i = 0; secclass_map[i].name; i++) { + const struct security_class_mapping *map = &secclass_map[i]; + int len; + char *name = stoupperx(map->name); + + len = strlen(name); + for (j = 0; map->perms[j]; j++) { + char *permname; + + if (j >= 32) { + fprintf(stderr, "Too many permissions to fit into an access vector at (%s, %s).\n", + map->name, map->perms[j]); + exit(5); + } + permname = stoupperx(map->perms[j]); + fprintf(fout, "#define %s__%-*s 0x%08xU\n", name, + 39-len, permname, 1U<