From 2645d432051cd4e6c04ee8af23be07c92f1f52a2 Mon Sep 17 00:00:00 2001 From: Changbin Du Date: Fri, 18 Sep 2020 21:20:42 -0700 Subject: kcsan: kconfig: move to menu 'Generic Kernel Debugging Instruments' This moves the KCSAN kconfig items under menu 'Generic Kernel Debugging Instruments' where UBSAN resides. Signed-off-by: Changbin Du Signed-off-by: Andrew Morton Tested-by: Randy Dunlap Reviewed-by: Randy Dunlap Cc: Greg Kroah-Hartman Cc: Marco Elver Link: https://lkml.kernel.org/r/20200904152224.5570-1-changbin.du@gmail.com Signed-off-by: Linus Torvalds --- lib/Kconfig.debug | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'lib') diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index e068c3c7189a..0c781f912f9f 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -520,8 +520,8 @@ config DEBUG_FS_ALLOW_NONE endchoice source "lib/Kconfig.kgdb" - source "lib/Kconfig.ubsan" +source "lib/Kconfig.kcsan" endmenu @@ -1620,8 +1620,6 @@ config PROVIDE_OHCI1394_DMA_INIT source "samples/Kconfig" -source "lib/Kconfig.kcsan" - config ARCH_HAS_DEVMEM_IS_ALLOWED bool -- cgit v1.2.3 From 769f5083c5e2de371d9a451e3bb9d4aaa24f3346 Mon Sep 17 00:00:00 2001 From: Colin Ian King Date: Fri, 18 Sep 2020 22:51:26 +0100 Subject: rhashtable: fix indentation of a continue statement A continue statement is indented incorrectly, add in the missing tab. Signed-off-by: Colin Ian King Acked-by: Herbert Xu Signed-off-by: David S. Miller --- lib/test_rhashtable.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'lib') diff --git a/lib/test_rhashtable.c b/lib/test_rhashtable.c index c5a6fef7b45d..76c607ee6db5 100644 --- a/lib/test_rhashtable.c +++ b/lib/test_rhashtable.c @@ -434,7 +434,7 @@ static int __init test_rhltable(unsigned int entries) } else { if (WARN(err != -ENOENT, "removed non-existent element, error %d not %d", err, -ENOENT)) - continue; + continue; } } -- cgit v1.2.3 From ead1e19ad905b97261f0ad7a98bb64abb9323b2b Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Mon, 21 Sep 2020 18:44:42 +0900 Subject: lib/bootconfig: Fix a bug of breaking existing tree nodes Fix a bug of breaking existing tree nodes by parsing the second and subsequent braces. Since the bootconfig parser uses the node.next field as a flag of current parent node, but this will break the existing tree if the same key node is specified again in the bootconfig. For example, the following bootconfig should be foo.buz and bar. foo bar foo { buz } However, when parsing the brace "{", it breaks foo->bar link by marking open-brace node. So the bootconfig unlinks bar from the bootconfig internal tree. This introduces a stack outside of the tree and record the last open-brace on the stack instead of using node.next field. Link: https://lkml.kernel.org/r/160068148267.1088739.8264704338030168660.stgit@devnote2 Fixes: 76db5a27a827 ("bootconfig: Add Extra Boot Config support") Cc: Ingo Molnar Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) --- lib/bootconfig.c | 36 +++++++++++++++++++++++------------- 1 file changed, 23 insertions(+), 13 deletions(-) (limited to 'lib') diff --git a/lib/bootconfig.c b/lib/bootconfig.c index 2c905a91d4eb..b44bba0f1583 100644 --- a/lib/bootconfig.c +++ b/lib/bootconfig.c @@ -31,6 +31,8 @@ static size_t xbc_data_size __initdata; static struct xbc_node *last_parent __initdata; static const char *xbc_err_msg __initdata; static int xbc_err_pos __initdata; +static int open_brace[XBC_DEPTH_MAX] __initdata; +static int brace_index __initdata; static int __init xbc_parse_error(const char *msg, const char *p) { @@ -431,27 +433,27 @@ static char *skip_spaces_until_newline(char *p) return p; } -static int __init __xbc_open_brace(void) +static int __init __xbc_open_brace(char *p) { - /* Mark the last key as open brace */ - last_parent->next = XBC_NODE_MAX; + /* Push the last key as open brace */ + open_brace[brace_index++] = xbc_node_index(last_parent); + if (brace_index >= XBC_DEPTH_MAX) + return xbc_parse_error("Exceed max depth of braces", p); return 0; } static int __init __xbc_close_brace(char *p) { - struct xbc_node *node; - - if (!last_parent || last_parent->next != XBC_NODE_MAX) + brace_index--; + if (!last_parent || brace_index < 0 || + (open_brace[brace_index] != xbc_node_index(last_parent))) return xbc_parse_error("Unexpected closing brace", p); - node = last_parent; - node->next = 0; - do { - node = xbc_node_get_parent(node); - } while (node && node->next != XBC_NODE_MAX); - last_parent = node; + if (brace_index == 0) + last_parent = NULL; + else + last_parent = &xbc_nodes[open_brace[brace_index - 1]]; return 0; } @@ -661,7 +663,7 @@ static int __init xbc_open_brace(char **k, char *n) return ret; *k = n; - return __xbc_open_brace(); + return __xbc_open_brace(n - 1); } static int __init xbc_close_brace(char **k, char *n) @@ -681,6 +683,13 @@ static int __init xbc_verify_tree(void) int i, depth, len, wlen; struct xbc_node *n, *m; + /* Brace closing */ + if (brace_index) { + n = &xbc_nodes[open_brace[brace_index]]; + return xbc_parse_error("Brace is not closed", + xbc_node_get_data(n)); + } + /* Empty tree */ if (xbc_node_num == 0) { xbc_parse_error("Empty config", xbc_data); @@ -745,6 +754,7 @@ void __init xbc_destroy_all(void) xbc_node_num = 0; memblock_free(__pa(xbc_nodes), sizeof(struct xbc_node) * XBC_NODE_MAX); xbc_nodes = NULL; + brace_index = 0; } /** -- cgit v1.2.3 From c7af4ecdffe1537ba8aeed0ac12c3326f908df43 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Mon, 21 Sep 2020 18:44:51 +0900 Subject: lib/bootconfig: Fix to remove tailing spaces after value Fix to remove tailing spaces after value. If there is a space after value, the bootconfig failed to remove it because it applies strim() before replacing the delimiter with null. For example, foo = var # comment was parsed as below. foo="var " but user will expect foo="var" This fixes it by applying strim() after removing the delimiter. Link: https://lkml.kernel.org/r/160068149134.1088739.8868306567670058853.stgit@devnote2 Fixes: 76db5a27a827 ("bootconfig: Add Extra Boot Config support") Cc: Ingo Molnar Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) --- lib/bootconfig.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'lib') diff --git a/lib/bootconfig.c b/lib/bootconfig.c index b44bba0f1583..649ed44f199c 100644 --- a/lib/bootconfig.c +++ b/lib/bootconfig.c @@ -494,8 +494,8 @@ static int __init __xbc_parse_value(char **__v, char **__n) break; } if (strchr(",;\n#}", c)) { - v = strim(v); *p++ = '\0'; + v = strim(v); break; } } -- cgit v1.2.3 From 1e1b6d63d6340764e00356873e5794225a2a03ea Mon Sep 17 00:00:00 2001 From: Nick Desaulniers Date: Fri, 25 Sep 2020 21:19:18 -0700 Subject: lib/string.c: implement stpcpy LLVM implemented a recent "libcall optimization" that lowers calls to `sprintf(dest, "%s", str)` where the return value is used to `stpcpy(dest, str) - dest`. This generally avoids the machinery involved in parsing format strings. `stpcpy` is just like `strcpy` except it returns the pointer to the new tail of `dest`. This optimization was introduced into clang-12. Implement this so that we don't observe linkage failures due to missing symbol definitions for `stpcpy`. Similar to last year's fire drill with: commit 5f074f3e192f ("lib/string.c: implement a basic bcmp") The kernel is somewhere between a "freestanding" environment (no full libc) and "hosted" environment (many symbols from libc exist with the same type, function signature, and semantics). As Peter Anvin notes, there's not really a great way to inform the compiler that you're targeting a freestanding environment but would like to opt-in to some libcall optimizations (see pr/47280 below), rather than opt-out. Arvind notes, -fno-builtin-* behaves slightly differently between GCC and Clang, and Clang is missing many __builtin_* definitions, which I consider a bug in Clang and am working on fixing. Masahiro summarizes the subtle distinction between compilers justly: To prevent transformation from foo() into bar(), there are two ways in Clang to do that; -fno-builtin-foo, and -fno-builtin-bar. There is only one in GCC; -fno-buitin-foo. (Any difference in that behavior in Clang is likely a bug from a missing __builtin_* definition.) Masahiro also notes: We want to disable optimization from foo() to bar(), but we may still benefit from the optimization from foo() into something else. If GCC implements the same transform, we would run into a problem because it is not -fno-builtin-bar, but -fno-builtin-foo that disables that optimization. In this regard, -fno-builtin-foo would be more future-proof than -fno-built-bar, but -fno-builtin-foo is still potentially overkill. We may want to prevent calls from foo() being optimized into calls to bar(), but we still may want other optimization on calls to foo(). It seems that compilers today don't quite provide the fine grain control over which libcall optimizations pseudo-freestanding environments would prefer. Finally, Kees notes that this interface is unsafe, so we should not encourage its use. As such, I've removed the declaration from any header, but it still needs to be exported to avoid linkage errors in modules. Reported-by: Sami Tolvanen Suggested-by: Andy Lavr Suggested-by: Arvind Sankar Suggested-by: Joe Perches Suggested-by: Kees Cook Suggested-by: Masahiro Yamada Suggested-by: Rasmus Villemoes Signed-off-by: Nick Desaulniers Signed-off-by: Andrew Morton Tested-by: Nathan Chancellor Cc: Link: https://lkml.kernel.org/r/20200914161643.938408-1-ndesaulniers@google.com Link: https://bugs.llvm.org/show_bug.cgi?id=47162 Link: https://bugs.llvm.org/show_bug.cgi?id=47280 Link: https://github.com/ClangBuiltLinux/linux/issues/1126 Link: https://man7.org/linux/man-pages/man3/stpcpy.3.html Link: https://pubs.opengroup.org/onlinepubs/9699919799/functions/stpcpy.html Link: https://reviews.llvm.org/D85963 Signed-off-by: Linus Torvalds --- lib/string.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) (limited to 'lib') diff --git a/lib/string.c b/lib/string.c index 6012c385fb31..4288e0158d47 100644 --- a/lib/string.c +++ b/lib/string.c @@ -272,6 +272,30 @@ ssize_t strscpy_pad(char *dest, const char *src, size_t count) } EXPORT_SYMBOL(strscpy_pad); +/** + * stpcpy - copy a string from src to dest returning a pointer to the new end + * of dest, including src's %NUL-terminator. May overrun dest. + * @dest: pointer to end of string being copied into. Must be large enough + * to receive copy. + * @src: pointer to the beginning of string being copied from. Must not overlap + * dest. + * + * stpcpy differs from strcpy in a key way: the return value is a pointer + * to the new %NUL-terminating character in @dest. (For strcpy, the return + * value is a pointer to the start of @dest). This interface is considered + * unsafe as it doesn't perform bounds checking of the inputs. As such it's + * not recommended for usage. Instead, its definition is provided in case + * the compiler lowers other libcalls to stpcpy. + */ +char *stpcpy(char *__restrict__ dest, const char *__restrict__ src); +char *stpcpy(char *__restrict__ dest, const char *__restrict__ src) +{ + while ((*dest++ = *src++) != '\0') + /* nothing */; + return --dest; +} +EXPORT_SYMBOL(stpcpy); + #ifndef __HAVE_ARCH_STRCAT /** * strcat - Append one %NUL-terminated string to another -- cgit v1.2.3 From ffa550cd691b8ba6c6117ce986516635afe03c13 Mon Sep 17 00:00:00 2001 From: Jason Yan Date: Fri, 25 Sep 2020 21:19:21 -0700 Subject: lib/memregion.c: include memregion.h This addresses the following sparse warning: lib/memregion.c:8:5: warning: symbol 'memregion_alloc' was not declared. Should it be static? lib/memregion.c:14:6: warning: symbol 'memregion_free' was not declared. Should it be static? Reported-by: Hulk Robot Signed-off-by: Jason Yan Signed-off-by: Andrew Morton Link: https://lkml.kernel.org/r/20200921142852.875312-1-yanaijie@huawei.com Signed-off-by: Linus Torvalds --- lib/memregion.c | 1 + 1 file changed, 1 insertion(+) (limited to 'lib') diff --git a/lib/memregion.c b/lib/memregion.c index 77c85b5251da..be5cfa5a3b57 100644 --- a/lib/memregion.c +++ b/lib/memregion.c @@ -2,6 +2,7 @@ /* identifiers for device / performance-differentiated memory regions */ #include #include +#include static DEFINE_IDA(memregion_ids); -- cgit v1.2.3