From 75c1182e18f4a66bbd2c91511b6b629dac6a27dc Mon Sep 17 00:00:00 2001 From: Bill Wendling Date: Thu, 7 Apr 2022 10:59:30 -0700 Subject: security: don't treat structure as an array of struct hlist_head The initialization of "security_hook_heads" is done by casting it to another structure pointer type, and treating it as an array of "struct hlist_head" objects. This requires an exception be made in "randstruct", because otherwise it will emit an error, reducing the effectiveness of the hardening technique. Instead of using a cast, initialize the individual struct hlist_head elements in security_hook_heads explicitly. This removes the need for the cast and randstruct exception. Signed-off-by: Bill Wendling Cc: Kees Cook Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20220407175930.471870-1-morbo@google.com --- scripts/gcc-plugins/randomize_layout_plugin.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'scripts/gcc-plugins/randomize_layout_plugin.c') diff --git a/scripts/gcc-plugins/randomize_layout_plugin.c b/scripts/gcc-plugins/randomize_layout_plugin.c index 334741a31d0a..c2ec81b68505 100644 --- a/scripts/gcc-plugins/randomize_layout_plugin.c +++ b/scripts/gcc-plugins/randomize_layout_plugin.c @@ -52,8 +52,6 @@ static const struct whitelist_entry whitelist[] = { { "net/unix/af_unix.c", "unix_skb_parms", "char" }, /* big_key payload.data struct splashing */ { "security/keys/big_key.c", "path", "void *" }, - /* walk struct security_hook_heads as an array of struct hlist_head */ - { "security/security.c", "hlist_head", "security_hook_heads" }, { } }; -- cgit From 61f60bac8c05f8ecd2ae2a6360520b91a45be9a2 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Tue, 10 May 2022 16:25:54 -0700 Subject: gcc-plugins: Change all version strings match kernel It's not meaningful for the GCC plugins to track their versions separately from the rest of the kernel. Switch all versions to the kernel version. Fix mismatched indenting while we're at it. Cc: linux-hardening@vger.kernel.org Signed-off-by: Kees Cook --- scripts/gcc-plugins/Makefile | 9 +++++---- scripts/gcc-plugins/latent_entropy_plugin.c | 2 +- scripts/gcc-plugins/randomize_layout_plugin.c | 2 +- scripts/gcc-plugins/sancov_plugin.c | 2 +- scripts/gcc-plugins/stackleak_plugin.c | 2 +- scripts/gcc-plugins/structleak_plugin.c | 2 +- 6 files changed, 10 insertions(+), 9 deletions(-) (limited to 'scripts/gcc-plugins/randomize_layout_plugin.c') diff --git a/scripts/gcc-plugins/Makefile b/scripts/gcc-plugins/Makefile index 148f4639cf09..6f0aecad5d67 100644 --- a/scripts/gcc-plugins/Makefile +++ b/scripts/gcc-plugins/Makefile @@ -28,10 +28,11 @@ GCC_PLUGINS_DIR = $(shell $(CC) -print-file-name=plugin) plugin_cxxflags = -Wp,-MMD,$(depfile) $(KBUILD_HOSTCXXFLAGS) -fPIC \ -include $(srctree)/include/linux/compiler-version.h \ - -I $(GCC_PLUGINS_DIR)/include -I $(obj) -std=gnu++11 \ - -fno-rtti -fno-exceptions -fasynchronous-unwind-tables \ - -ggdb -Wno-narrowing -Wno-unused-variable \ - -Wno-format-diag + -include $(objtree)/include/generated/utsrelease.h \ + -I $(GCC_PLUGINS_DIR)/include -I $(obj) -std=gnu++11 \ + -fno-rtti -fno-exceptions -fasynchronous-unwind-tables \ + -ggdb -Wno-narrowing -Wno-unused-variable \ + -Wno-format-diag plugin_ldflags = -shared diff --git a/scripts/gcc-plugins/latent_entropy_plugin.c b/scripts/gcc-plugins/latent_entropy_plugin.c index 8425da41de0d..5d415b2572a8 100644 --- a/scripts/gcc-plugins/latent_entropy_plugin.c +++ b/scripts/gcc-plugins/latent_entropy_plugin.c @@ -82,7 +82,7 @@ __visible int plugin_is_GPL_compatible; static GTY(()) tree latent_entropy_decl; static struct plugin_info latent_entropy_plugin_info = { - .version = "201606141920vanilla", + .version = UTS_RELEASE, .help = "disable\tturn off latent entropy instrumentation\n", }; diff --git a/scripts/gcc-plugins/randomize_layout_plugin.c b/scripts/gcc-plugins/randomize_layout_plugin.c index c2ec81b68505..19214e573137 100644 --- a/scripts/gcc-plugins/randomize_layout_plugin.c +++ b/scripts/gcc-plugins/randomize_layout_plugin.c @@ -34,7 +34,7 @@ __visible int plugin_is_GPL_compatible; static int performance_mode; static struct plugin_info randomize_layout_plugin_info = { - .version = "201402201816vanilla", + .version = UTS_RELEASE, .help = "disable\t\t\tdo not activate plugin\n" "performance-mode\tenable cacheline-aware layout randomization\n" }; diff --git a/scripts/gcc-plugins/sancov_plugin.c b/scripts/gcc-plugins/sancov_plugin.c index 23bd023a283b..f3d629555b84 100644 --- a/scripts/gcc-plugins/sancov_plugin.c +++ b/scripts/gcc-plugins/sancov_plugin.c @@ -26,7 +26,7 @@ __visible int plugin_is_GPL_compatible; tree sancov_fndecl; static struct plugin_info sancov_plugin_info = { - .version = "20160402", + .version = UTS_RELEASE, .help = "sancov plugin\n", }; diff --git a/scripts/gcc-plugins/stackleak_plugin.c b/scripts/gcc-plugins/stackleak_plugin.c index 42f0252ee2a4..de817d54b8af 100644 --- a/scripts/gcc-plugins/stackleak_plugin.c +++ b/scripts/gcc-plugins/stackleak_plugin.c @@ -44,7 +44,7 @@ static bool verbose = false; static GTY(()) tree track_function_decl; static struct plugin_info stackleak_plugin_info = { - .version = "201707101337", + .version = UTS_RELEASE, .help = "track-min-size=nn\ttrack stack for functions with a stack frame size >= nn bytes\n" "arch=target_arch\tspecify target build arch\n" "disable\t\tdo not activate the plugin\n" diff --git a/scripts/gcc-plugins/structleak_plugin.c b/scripts/gcc-plugins/structleak_plugin.c index 74e319288389..86b608a24ec0 100644 --- a/scripts/gcc-plugins/structleak_plugin.c +++ b/scripts/gcc-plugins/structleak_plugin.c @@ -37,7 +37,7 @@ __visible int plugin_is_GPL_compatible; static struct plugin_info structleak_plugin_info = { - .version = "20190125vanilla", + .version = UTS_RELEASE, .help = "disable\tdo not activate plugin\n" "byref\tinit structs passed by reference\n" "byref-all\tinit anything passed by reference\n" -- cgit From c1298a3a1139c9a73a188fbb153b6eb83dbd4d7d Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Sun, 8 May 2022 09:15:53 -0700 Subject: big_keys: Use struct for internal payload The randstruct GCC plugin gets upset when it sees struct path (which is randomized) being assigned from a "void *" (which it cannot type-check). There's no need for these casts, as the entire internal payload use is following a normal struct layout. Convert the enum-based void * offset dereferencing to the new big_key_payload struct. No meaningful machine code changes result after this change, and source readability is improved. Drop the randstruct exception now that there is no "confusing" cross-type assignment. Cc: David Howells Cc: Eric Biggers Cc: Christoph Hellwig Cc: Jarkko Sakkinen Cc: James Morris Cc: "Serge E. Hallyn" Cc: linux-hardening@vger.kernel.org Cc: keyrings@vger.kernel.org Cc: linux-security-module@vger.kernel.org Signed-off-by: Kees Cook --- scripts/gcc-plugins/randomize_layout_plugin.c | 2 - security/keys/big_key.c | 73 +++++++++++++-------------- 2 files changed, 36 insertions(+), 39 deletions(-) (limited to 'scripts/gcc-plugins/randomize_layout_plugin.c') diff --git a/scripts/gcc-plugins/randomize_layout_plugin.c b/scripts/gcc-plugins/randomize_layout_plugin.c index 19214e573137..5836a7fc7532 100644 --- a/scripts/gcc-plugins/randomize_layout_plugin.c +++ b/scripts/gcc-plugins/randomize_layout_plugin.c @@ -50,8 +50,6 @@ static const struct whitelist_entry whitelist[] = { { "drivers/net/ethernet/sun/niu.c", "page", "address_space" }, /* unix_skb_parms via UNIXCB() buffer */ { "net/unix/af_unix.c", "unix_skb_parms", "char" }, - /* big_key payload.data struct splashing */ - { "security/keys/big_key.c", "path", "void *" }, { } }; diff --git a/security/keys/big_key.c b/security/keys/big_key.c index d17e5f09eeb8..c3367622c683 100644 --- a/security/keys/big_key.c +++ b/security/keys/big_key.c @@ -20,12 +20,13 @@ /* * Layout of key payload words. */ -enum { - big_key_data, - big_key_path, - big_key_path_2nd_part, - big_key_len, +struct big_key_payload { + u8 *data; + struct path path; + size_t length; }; +#define to_big_key_payload(payload) \ + (struct big_key_payload *)((payload).data) /* * If the data is under this limit, there's no point creating a shm file to @@ -55,7 +56,7 @@ struct key_type key_type_big_key = { */ int big_key_preparse(struct key_preparsed_payload *prep) { - struct path *path = (struct path *)&prep->payload.data[big_key_path]; + struct big_key_payload *payload = to_big_key_payload(prep->payload); struct file *file; u8 *buf, *enckey; ssize_t written; @@ -63,13 +64,15 @@ int big_key_preparse(struct key_preparsed_payload *prep) size_t enclen = datalen + CHACHA20POLY1305_AUTHTAG_SIZE; int ret; + BUILD_BUG_ON(sizeof(*payload) != sizeof(prep->payload.data)); + if (datalen <= 0 || datalen > 1024 * 1024 || !prep->data) return -EINVAL; /* Set an arbitrary quota */ prep->quotalen = 16; - prep->payload.data[big_key_len] = (void *)(unsigned long)datalen; + payload->length = datalen; if (datalen > BIG_KEY_FILE_THRESHOLD) { /* Create a shmem file to store the data in. This will permit the data @@ -117,9 +120,9 @@ int big_key_preparse(struct key_preparsed_payload *prep) /* Pin the mount and dentry to the key so that we can open it again * later */ - prep->payload.data[big_key_data] = enckey; - *path = file->f_path; - path_get(path); + payload->data = enckey; + payload->path = file->f_path; + path_get(&payload->path); fput(file); kvfree_sensitive(buf, enclen); } else { @@ -129,7 +132,7 @@ int big_key_preparse(struct key_preparsed_payload *prep) if (!data) return -ENOMEM; - prep->payload.data[big_key_data] = data; + payload->data = data; memcpy(data, prep->data, prep->datalen); } return 0; @@ -148,12 +151,11 @@ error: */ void big_key_free_preparse(struct key_preparsed_payload *prep) { - if (prep->datalen > BIG_KEY_FILE_THRESHOLD) { - struct path *path = (struct path *)&prep->payload.data[big_key_path]; + struct big_key_payload *payload = to_big_key_payload(prep->payload); - path_put(path); - } - kfree_sensitive(prep->payload.data[big_key_data]); + if (prep->datalen > BIG_KEY_FILE_THRESHOLD) + path_put(&payload->path); + kfree_sensitive(payload->data); } /* @@ -162,13 +164,12 @@ void big_key_free_preparse(struct key_preparsed_payload *prep) */ void big_key_revoke(struct key *key) { - struct path *path = (struct path *)&key->payload.data[big_key_path]; + struct big_key_payload *payload = to_big_key_payload(key->payload); /* clear the quota */ key_payload_reserve(key, 0); - if (key_is_positive(key) && - (size_t)key->payload.data[big_key_len] > BIG_KEY_FILE_THRESHOLD) - vfs_truncate(path, 0); + if (key_is_positive(key) && payload->length > BIG_KEY_FILE_THRESHOLD) + vfs_truncate(&payload->path, 0); } /* @@ -176,17 +177,15 @@ void big_key_revoke(struct key *key) */ void big_key_destroy(struct key *key) { - size_t datalen = (size_t)key->payload.data[big_key_len]; - - if (datalen > BIG_KEY_FILE_THRESHOLD) { - struct path *path = (struct path *)&key->payload.data[big_key_path]; + struct big_key_payload *payload = to_big_key_payload(key->payload); - path_put(path); - path->mnt = NULL; - path->dentry = NULL; + if (payload->length > BIG_KEY_FILE_THRESHOLD) { + path_put(&payload->path); + payload->path.mnt = NULL; + payload->path.dentry = NULL; } - kfree_sensitive(key->payload.data[big_key_data]); - key->payload.data[big_key_data] = NULL; + kfree_sensitive(payload->data); + payload->data = NULL; } /* @@ -211,14 +210,14 @@ int big_key_update(struct key *key, struct key_preparsed_payload *prep) */ void big_key_describe(const struct key *key, struct seq_file *m) { - size_t datalen = (size_t)key->payload.data[big_key_len]; + struct big_key_payload *payload = to_big_key_payload(key->payload); seq_puts(m, key->description); if (key_is_positive(key)) seq_printf(m, ": %zu [%s]", - datalen, - datalen > BIG_KEY_FILE_THRESHOLD ? "file" : "buff"); + payload->length, + payload->length > BIG_KEY_FILE_THRESHOLD ? "file" : "buff"); } /* @@ -227,16 +226,16 @@ void big_key_describe(const struct key *key, struct seq_file *m) */ long big_key_read(const struct key *key, char *buffer, size_t buflen) { - size_t datalen = (size_t)key->payload.data[big_key_len]; + struct big_key_payload *payload = to_big_key_payload(key->payload); + size_t datalen = payload->length; long ret; if (!buffer || buflen < datalen) return datalen; if (datalen > BIG_KEY_FILE_THRESHOLD) { - struct path *path = (struct path *)&key->payload.data[big_key_path]; struct file *file; - u8 *buf, *enckey = (u8 *)key->payload.data[big_key_data]; + u8 *buf, *enckey = payload->data; size_t enclen = datalen + CHACHA20POLY1305_AUTHTAG_SIZE; loff_t pos = 0; @@ -244,7 +243,7 @@ long big_key_read(const struct key *key, char *buffer, size_t buflen) if (!buf) return -ENOMEM; - file = dentry_open(path, O_RDONLY, current_cred()); + file = dentry_open(&payload->path, O_RDONLY, current_cred()); if (IS_ERR(file)) { ret = PTR_ERR(file); goto error; @@ -274,7 +273,7 @@ error: kvfree_sensitive(buf, enclen); } else { ret = datalen; - memcpy(buffer, key->payload.data[big_key_data], datalen); + memcpy(buffer, payload->data, datalen); } return ret; -- cgit From 2dcfe9e2d370f6643486e327c6ae17af8887756c Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Mon, 9 May 2022 15:11:54 -0700 Subject: niu: Silence randstruct warnings Clang randstruct gets upset when it sees struct addresspace (which is randomized) being assigned to a struct page (which is not randomized): drivers/net/ethernet/sun/niu.c:3385:12: error: casting from randomized structure pointer type 'struct address_space *' to 'struct page *' *link = (struct page *) page->mapping; ^ It looks like niu.c is looking for an in-line place to chain its allocated pages together and is overloading the "mapping" member, as it is unused. This is very non-standard, and is expected to be cleaned up in the future[1], but there is no "correct" way to handle it today. No meaningful machine code changes result after this change, and source readability is improved. Drop the randstruct exception now that there is no "confusing" cross-type assignment. [1] https://lore.kernel.org/lkml/YnqgjVoMDu5v9PNG@casper.infradead.org/ Cc: "Matthew Wilcox (Oracle)" Cc: Christoph Hellwig Cc: "David S. Miller" Cc: Jakub Kicinski Cc: Paolo Abeni Cc: Du Cheng Cc: Christophe JAILLET Cc: Vlastimil Babka Cc: William Kucharski Cc: Arnd Bergmann Cc: Nathan Chancellor Cc: netdev@vger.kernel.org Cc: linux-mm@kvack.org Cc: linux-hardening@vger.kernel.org Acked-by: Jakub Kicinski Link: https://lore.kernel.org/lkml/20220511151647.7290adbe@kernel.org Signed-off-by: Kees Cook --- drivers/net/ethernet/sun/niu.c | 41 ++++++++++++++++++++------- scripts/gcc-plugins/randomize_layout_plugin.c | 2 -- 2 files changed, 31 insertions(+), 12 deletions(-) (limited to 'scripts/gcc-plugins/randomize_layout_plugin.c') diff --git a/drivers/net/ethernet/sun/niu.c b/drivers/net/ethernet/sun/niu.c index 42460c0885fc..df70df29deea 100644 --- a/drivers/net/ethernet/sun/niu.c +++ b/drivers/net/ethernet/sun/niu.c @@ -35,6 +35,25 @@ #include "niu.h" +/* This driver wants to store a link to a "next page" within the + * page struct itself by overloading the content of the "mapping" + * member. This is not expected by the page API, but does currently + * work. However, the randstruct plugin gets very bothered by this + * case because "mapping" (struct address_space) is randomized, so + * casts to/from it trigger warnings. Hide this by way of a union, + * to create a typed alias of "mapping", since that's how it is + * actually being used here. + */ +union niu_page { + struct page page; + struct { + unsigned long __flags; /* unused alias of "flags" */ + struct list_head __lru; /* unused alias of "lru" */ + struct page *next; /* alias of "mapping" */ + }; +}; +#define niu_next_page(p) container_of(p, union niu_page, page)->next + #define DRV_MODULE_NAME "niu" #define DRV_MODULE_VERSION "1.1" #define DRV_MODULE_RELDATE "Apr 22, 2010" @@ -3283,7 +3302,7 @@ static struct page *niu_find_rxpage(struct rx_ring_info *rp, u64 addr, addr &= PAGE_MASK; pp = &rp->rxhash[h]; - for (; (p = *pp) != NULL; pp = (struct page **) &p->mapping) { + for (; (p = *pp) != NULL; pp = &niu_next_page(p)) { if (p->index == addr) { *link = pp; goto found; @@ -3300,7 +3319,7 @@ static void niu_hash_page(struct rx_ring_info *rp, struct page *page, u64 base) unsigned int h = niu_hash_rxaddr(rp, base); page->index = base; - page->mapping = (struct address_space *) rp->rxhash[h]; + niu_next_page(page) = rp->rxhash[h]; rp->rxhash[h] = page; } @@ -3382,11 +3401,11 @@ static int niu_rx_pkt_ignore(struct niu *np, struct rx_ring_info *rp) rcr_size = rp->rbr_sizes[(val & RCR_ENTRY_PKTBUFSZ) >> RCR_ENTRY_PKTBUFSZ_SHIFT]; if ((page->index + PAGE_SIZE) - rcr_size == addr) { - *link = (struct page *) page->mapping; + *link = niu_next_page(page); np->ops->unmap_page(np->device, page->index, PAGE_SIZE, DMA_FROM_DEVICE); page->index = 0; - page->mapping = NULL; + niu_next_page(page) = NULL; __free_page(page); rp->rbr_refill_pending++; } @@ -3451,11 +3470,11 @@ static int niu_process_rx_pkt(struct napi_struct *napi, struct niu *np, niu_rx_skb_append(skb, page, off, append_size, rcr_size); if ((page->index + rp->rbr_block_size) - rcr_size == addr) { - *link = (struct page *) page->mapping; + *link = niu_next_page(page); np->ops->unmap_page(np->device, page->index, PAGE_SIZE, DMA_FROM_DEVICE); page->index = 0; - page->mapping = NULL; + niu_next_page(page) = NULL; rp->rbr_refill_pending++; } else get_page(page); @@ -3518,13 +3537,13 @@ static void niu_rbr_free(struct niu *np, struct rx_ring_info *rp) page = rp->rxhash[i]; while (page) { - struct page *next = (struct page *) page->mapping; + struct page *next = niu_next_page(page); u64 base = page->index; np->ops->unmap_page(np->device, base, PAGE_SIZE, DMA_FROM_DEVICE); page->index = 0; - page->mapping = NULL; + niu_next_page(page) = NULL; __free_page(page); @@ -6440,8 +6459,7 @@ static void niu_reset_buffers(struct niu *np) page = rp->rxhash[j]; while (page) { - struct page *next = - (struct page *) page->mapping; + struct page *next = niu_next_page(page); u64 base = page->index; base = base >> RBR_DESCR_ADDR_SHIFT; rp->rbr[k++] = cpu_to_le32(base); @@ -10176,6 +10194,9 @@ static int __init niu_init(void) BUILD_BUG_ON(PAGE_SIZE < 4 * 1024); + BUILD_BUG_ON(offsetof(struct page, mapping) != + offsetof(union niu_page, next)); + niu_debug = netif_msg_init(debug, NIU_MSG_DEFAULT); #ifdef CONFIG_SPARC64 diff --git a/scripts/gcc-plugins/randomize_layout_plugin.c b/scripts/gcc-plugins/randomize_layout_plugin.c index 5836a7fc7532..c9d345a91c41 100644 --- a/scripts/gcc-plugins/randomize_layout_plugin.c +++ b/scripts/gcc-plugins/randomize_layout_plugin.c @@ -46,8 +46,6 @@ struct whitelist_entry { }; static const struct whitelist_entry whitelist[] = { - /* NIU overloads mapping with page struct */ - { "drivers/net/ethernet/sun/niu.c", "page", "address_space" }, /* unix_skb_parms via UNIXCB() buffer */ { "net/unix/af_unix.c", "unix_skb_parms", "char" }, { } -- cgit From b146cbf2e32f01f56244d670aef2f43d44fcf120 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Tue, 10 May 2022 15:46:26 -0700 Subject: af_unix: Silence randstruct GCC plugin warning While preparing for Clang randstruct support (which duplicated many of the warnings the randstruct GCC plugin warned about), one strange one remained only for the randstruct GCC plugin. Eliminating this rids the plugin of the last exception. It seems the plugin is happy to dereference individual members of a cross-struct cast, but it is upset about casting to a whole object pointer. This only manifests in one place in the kernel, so just replace the variable with individual member accesses. There is no change in executable instruction output. Drop the last exception from the randstruct GCC plugin. Cc: "David S. Miller" Cc: Christoph Hellwig Cc: Paolo Abeni Cc: Alexei Starovoitov Cc: Cong Wang Cc: Al Viro Cc: netdev@vger.kernel.org Cc: linux-hardening@vger.kernel.org Acked-by: Kuniyuki Iwashima Link: https://lore.kernel.org/lkml/20220511022217.58586-1-kuniyu@amazon.co.jp Acked-by: Jakub Kicinski Link: https://lore.kernel.org/lkml/20220511151542.4cb3ff17@kernel.org Signed-off-by: Kees Cook --- net/unix/af_unix.c | 8 +++----- scripts/gcc-plugins/randomize_layout_plugin.c | 2 -- 2 files changed, 3 insertions(+), 7 deletions(-) (limited to 'scripts/gcc-plugins/randomize_layout_plugin.c') diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c index e71a312faa1e..36367e7e3e0a 100644 --- a/net/unix/af_unix.c +++ b/net/unix/af_unix.c @@ -1808,11 +1808,9 @@ static int maybe_init_creds(struct scm_cookie *scm, static bool unix_skb_scm_eq(struct sk_buff *skb, struct scm_cookie *scm) { - const struct unix_skb_parms *u = &UNIXCB(skb); - - return u->pid == scm->pid && - uid_eq(u->uid, scm->creds.uid) && - gid_eq(u->gid, scm->creds.gid) && + return UNIXCB(skb).pid == scm->pid && + uid_eq(UNIXCB(skb).uid, scm->creds.uid) && + gid_eq(UNIXCB(skb).gid, scm->creds.gid) && unix_secdata_eq(scm, skb); } diff --git a/scripts/gcc-plugins/randomize_layout_plugin.c b/scripts/gcc-plugins/randomize_layout_plugin.c index c9d345a91c41..2ca768d88a68 100644 --- a/scripts/gcc-plugins/randomize_layout_plugin.c +++ b/scripts/gcc-plugins/randomize_layout_plugin.c @@ -46,8 +46,6 @@ struct whitelist_entry { }; static const struct whitelist_entry whitelist[] = { - /* unix_skb_parms via UNIXCB() buffer */ - { "net/unix/af_unix.c", "unix_skb_parms", "char" }, { } }; -- cgit From 710e4ebfbacac53b05c86a01e6d636c69f6eca9f Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Tue, 10 May 2022 16:22:45 -0700 Subject: gcc-plugins: randstruct: Remove cast exception handling With all randstruct exceptions removed, remove all the exception handling code. Any future warnings are likely to be shared between this plugin and Clang randstruct, and will need to be addressed in a more wholistic fashion. Cc: Christoph Hellwig Cc: linux-hardening@vger.kernel.org Signed-off-by: Kees Cook --- scripts/gcc-plugins/randomize_layout_plugin.c | 79 +-------------------------- 1 file changed, 3 insertions(+), 76 deletions(-) (limited to 'scripts/gcc-plugins/randomize_layout_plugin.c') diff --git a/scripts/gcc-plugins/randomize_layout_plugin.c b/scripts/gcc-plugins/randomize_layout_plugin.c index 2ca768d88a68..ea2aea570404 100644 --- a/scripts/gcc-plugins/randomize_layout_plugin.c +++ b/scripts/gcc-plugins/randomize_layout_plugin.c @@ -39,16 +39,6 @@ static struct plugin_info randomize_layout_plugin_info = { "performance-mode\tenable cacheline-aware layout randomization\n" }; -struct whitelist_entry { - const char *pathname; - const char *lhs; - const char *rhs; -}; - -static const struct whitelist_entry whitelist[] = { - { } -}; - /* from old Linux dcache.h */ static inline unsigned long partial_name_hash(unsigned long c, unsigned long prevhash) @@ -734,60 +724,6 @@ static void handle_local_var_initializers(void) } } -static bool type_name_eq(gimple stmt, const_tree type_tree, const char *wanted_name) -{ - const char *type_name; - - if (type_tree == NULL_TREE) - return false; - - switch (TREE_CODE(type_tree)) { - case RECORD_TYPE: - type_name = TYPE_NAME_POINTER(type_tree); - break; - case INTEGER_TYPE: - if (TYPE_PRECISION(type_tree) == CHAR_TYPE_SIZE) - type_name = "char"; - else { - INFORM(gimple_location(stmt), "found non-char INTEGER_TYPE cast comparison: %qT\n", type_tree); - debug_tree(type_tree); - return false; - } - break; - case POINTER_TYPE: - if (TREE_CODE(TREE_TYPE(type_tree)) == VOID_TYPE) { - type_name = "void *"; - break; - } else { - INFORM(gimple_location(stmt), "found non-void POINTER_TYPE cast comparison %qT\n", type_tree); - debug_tree(type_tree); - return false; - } - default: - INFORM(gimple_location(stmt), "unhandled cast comparison: %qT\n", type_tree); - debug_tree(type_tree); - return false; - } - - return strcmp(type_name, wanted_name) == 0; -} - -static bool whitelisted_cast(gimple stmt, const_tree lhs_tree, const_tree rhs_tree) -{ - const struct whitelist_entry *entry; - expanded_location xloc = expand_location(gimple_location(stmt)); - - for (entry = whitelist; entry->pathname; entry++) { - if (!strstr(xloc.file, entry->pathname)) - continue; - - if (type_name_eq(stmt, lhs_tree, entry->lhs) && type_name_eq(stmt, rhs_tree, entry->rhs)) - return true; - } - - return false; -} - /* * iterate over all statements to find "bad" casts: * those where the address of the start of a structure is cast @@ -864,10 +800,7 @@ static unsigned int find_bad_casts_execute(void) #ifndef __DEBUG_PLUGIN if (lookup_attribute("randomize_performed", TYPE_ATTRIBUTES(ptr_lhs_type))) #endif - { - if (!whitelisted_cast(stmt, ptr_lhs_type, ptr_rhs_type)) - MISMATCH(gimple_location(stmt), "rhs", ptr_lhs_type, ptr_rhs_type); - } + MISMATCH(gimple_location(stmt), "rhs", ptr_lhs_type, ptr_rhs_type); continue; } @@ -890,10 +823,7 @@ static unsigned int find_bad_casts_execute(void) #ifndef __DEBUG_PLUGIN if (lookup_attribute("randomize_performed", TYPE_ATTRIBUTES(op0_type))) #endif - { - if (!whitelisted_cast(stmt, ptr_lhs_type, op0_type)) - MISMATCH(gimple_location(stmt), "op0", ptr_lhs_type, op0_type); - } + MISMATCH(gimple_location(stmt), "op0", ptr_lhs_type, op0_type); } else { const_tree ssa_name_var = SSA_NAME_VAR(rhs1); /* skip bogus type casts introduced by container_of */ @@ -903,10 +833,7 @@ static unsigned int find_bad_casts_execute(void) #ifndef __DEBUG_PLUGIN if (lookup_attribute("randomize_performed", TYPE_ATTRIBUTES(ptr_rhs_type))) #endif - { - if (!whitelisted_cast(stmt, ptr_lhs_type, ptr_rhs_type)) - MISMATCH(gimple_location(stmt), "ssa", ptr_lhs_type, ptr_rhs_type); - } + MISMATCH(gimple_location(stmt), "ssa", ptr_lhs_type, ptr_rhs_type); } } -- cgit From d37aa2efc89b387cda93bf15317883519683d435 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Tue, 24 May 2022 22:55:41 +0900 Subject: gcc-plugins: use KERNELVERSION for plugin version Commit 61f60bac8c05 ("gcc-plugins: Change all version strings match kernel") broke parallel builds. Instead of adding the dependency between GCC plugins and utsrelease.h, let's use KERNELVERSION, which does not require any build artifact. Another reason why I want to avoid utsrelease.h is because it depends on CONFIG_LOCALVERSION(_AUTO) and localversion* files. (include/generated/utsrelease.h depends on include/config/kernel.release, which is generated by scripts/setlocalversion) I want to keep host tools independent of the kernel configuration. There is no good reason to rebuild GCC plugins just because of CONFIG_LOCALVERSION being changed. We just want to associate the plugin versions with the kernel source version. KERNELVERSION should be enough for our purpose. Fixes: 61f60bac8c05 ("gcc-plugins: Change all version strings match kernel") Reported-by: kernel test robot Link: https://lore.kernel.org/linux-mm/202205230239.EZxeZ3Fv-lkp@intel.com Reported-by: Guenter Roeck Signed-off-by: Masahiro Yamada Signed-off-by: Kees Cook Link: https://lore.kernel.org/r/20220524135541.1453693-1-masahiroy@kernel.org --- scripts/gcc-plugins/Makefile | 2 +- scripts/gcc-plugins/latent_entropy_plugin.c | 2 +- scripts/gcc-plugins/randomize_layout_plugin.c | 2 +- scripts/gcc-plugins/sancov_plugin.c | 2 +- scripts/gcc-plugins/stackleak_plugin.c | 2 +- scripts/gcc-plugins/structleak_plugin.c | 2 +- 6 files changed, 6 insertions(+), 6 deletions(-) (limited to 'scripts/gcc-plugins/randomize_layout_plugin.c') diff --git a/scripts/gcc-plugins/Makefile b/scripts/gcc-plugins/Makefile index 6f0aecad5d67..b34d11e22636 100644 --- a/scripts/gcc-plugins/Makefile +++ b/scripts/gcc-plugins/Makefile @@ -28,7 +28,7 @@ GCC_PLUGINS_DIR = $(shell $(CC) -print-file-name=plugin) plugin_cxxflags = -Wp,-MMD,$(depfile) $(KBUILD_HOSTCXXFLAGS) -fPIC \ -include $(srctree)/include/linux/compiler-version.h \ - -include $(objtree)/include/generated/utsrelease.h \ + -DPLUGIN_VERSION=$(call stringify,$(KERNELVERSION)) \ -I $(GCC_PLUGINS_DIR)/include -I $(obj) -std=gnu++11 \ -fno-rtti -fno-exceptions -fasynchronous-unwind-tables \ -ggdb -Wno-narrowing -Wno-unused-variable \ diff --git a/scripts/gcc-plugins/latent_entropy_plugin.c b/scripts/gcc-plugins/latent_entropy_plugin.c index 5d415b2572a8..848918764174 100644 --- a/scripts/gcc-plugins/latent_entropy_plugin.c +++ b/scripts/gcc-plugins/latent_entropy_plugin.c @@ -82,7 +82,7 @@ __visible int plugin_is_GPL_compatible; static GTY(()) tree latent_entropy_decl; static struct plugin_info latent_entropy_plugin_info = { - .version = UTS_RELEASE, + .version = PLUGIN_VERSION, .help = "disable\tturn off latent entropy instrumentation\n", }; diff --git a/scripts/gcc-plugins/randomize_layout_plugin.c b/scripts/gcc-plugins/randomize_layout_plugin.c index ea2aea570404..951b74ba1b24 100644 --- a/scripts/gcc-plugins/randomize_layout_plugin.c +++ b/scripts/gcc-plugins/randomize_layout_plugin.c @@ -34,7 +34,7 @@ __visible int plugin_is_GPL_compatible; static int performance_mode; static struct plugin_info randomize_layout_plugin_info = { - .version = UTS_RELEASE, + .version = PLUGIN_VERSION, .help = "disable\t\t\tdo not activate plugin\n" "performance-mode\tenable cacheline-aware layout randomization\n" }; diff --git a/scripts/gcc-plugins/sancov_plugin.c b/scripts/gcc-plugins/sancov_plugin.c index f3d629555b84..b76cb9c42cec 100644 --- a/scripts/gcc-plugins/sancov_plugin.c +++ b/scripts/gcc-plugins/sancov_plugin.c @@ -26,7 +26,7 @@ __visible int plugin_is_GPL_compatible; tree sancov_fndecl; static struct plugin_info sancov_plugin_info = { - .version = UTS_RELEASE, + .version = PLUGIN_VERSION, .help = "sancov plugin\n", }; diff --git a/scripts/gcc-plugins/stackleak_plugin.c b/scripts/gcc-plugins/stackleak_plugin.c index de817d54b8af..ff91885f9470 100644 --- a/scripts/gcc-plugins/stackleak_plugin.c +++ b/scripts/gcc-plugins/stackleak_plugin.c @@ -44,7 +44,7 @@ static bool verbose = false; static GTY(()) tree track_function_decl; static struct plugin_info stackleak_plugin_info = { - .version = UTS_RELEASE, + .version = PLUGIN_VERSION, .help = "track-min-size=nn\ttrack stack for functions with a stack frame size >= nn bytes\n" "arch=target_arch\tspecify target build arch\n" "disable\t\tdo not activate the plugin\n" diff --git a/scripts/gcc-plugins/structleak_plugin.c b/scripts/gcc-plugins/structleak_plugin.c index 86b608a24ec0..8bc04068ed39 100644 --- a/scripts/gcc-plugins/structleak_plugin.c +++ b/scripts/gcc-plugins/structleak_plugin.c @@ -37,7 +37,7 @@ __visible int plugin_is_GPL_compatible; static struct plugin_info structleak_plugin_info = { - .version = UTS_RELEASE, + .version = PLUGIN_VERSION, .help = "disable\tdo not activate plugin\n" "byref\tinit structs passed by reference\n" "byref-all\tinit anything passed by reference\n" -- cgit