From 741e49eacdcd31ec9b448a77b1ab9219a00c1db9 Mon Sep 17 00:00:00 2001 From: Alexander Lobakin Date: Tue, 24 May 2022 17:27:18 +0200 Subject: modpost: fix removing numeric suffixes [ Upstream commit b5beffa20d83c4e15306c991ffd00de0d8628338 ] With the `-z unique-symbol` linker flag or any similar mechanism, it is possible to trigger the following: ERROR: modpost: "param_set_uint.0" [vmlinux] is a static EXPORT_SYMBOL The reason is that for now the condition from remove_dot(): if (m && (s[n + m] == '.' || s[n + m] == 0)) which was designed to test if it's a dot or a '\0' after the suffix is never satisfied. This is due to that `s[n + m]` always points to the last digit of a numeric suffix, not on the symbol next to it (from a custom debug print added to modpost): param_set_uint.0, s[n + m] is '0', s[n + m + 1] is '\0' So it's off-by-one and was like that since 2014. Fix this for the sake of any potential upcoming features, but don't bother stable-backporting, as it's well hidden -- apart from that LD flag, it can be triggered only with GCC LTO which never landed upstream. Fixes: fcd38ed0ff26 ("scripts: modpost: fix compilation warning") Signed-off-by: Alexander Lobakin Reviewed-by: Petr Mladek Signed-off-by: Masahiro Yamada Signed-off-by: Sasha Levin --- scripts/mod/modpost.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts/mod/modpost.c') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index e08f75aed429..a21aa74b4948 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1982,7 +1982,7 @@ static char *remove_dot(char *s) if (n && s[n]) { size_t m = strspn(s + n + 1, "0123456789"); - if (m && (s[n + m] == '.' || s[n + m] == 0)) + if (m && (s[n + m + 1] == '.' || s[n + m + 1] == 0)) s[n] = 0; } return s; -- cgit v1.2.3 From 82876878210ac3b0855742861d4cd0be78ff0315 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Tue, 24 May 2022 01:46:22 +0900 Subject: modpost: fix undefined behavior of is_arm_mapping_symbol() [ Upstream commit d6b732666a1bae0df3c3ae06925043bba34502b1 ] The return value of is_arm_mapping_symbol() is unpredictable when "$" is passed in. strchr(3) says: The strchr() and strrchr() functions return a pointer to the matched character or NULL if the character is not found. The terminating null byte is considered part of the string, so that if c is specified as '\0', these functions return a pointer to the terminator. When str[1] is '\0', strchr("axtd", str[1]) is not NULL, and str[2] is referenced (i.e. buffer overrun). Test code --------- char str1[] = "abc"; char str2[] = "ab"; strcpy(str1, "$"); strcpy(str2, "$"); printf("test1: %d\n", is_arm_mapping_symbol(str1)); printf("test2: %d\n", is_arm_mapping_symbol(str2)); Result ------ test1: 0 test2: 1 Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers Signed-off-by: Sasha Levin --- scripts/mod/modpost.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'scripts/mod/modpost.c') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index a21aa74b4948..79aef50ede17 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1271,7 +1271,8 @@ static int secref_whitelist(const struct sectioncheck *mismatch, static inline int is_arm_mapping_symbol(const char *str) { - return str[0] == '$' && strchr("axtd", str[1]) + return str[0] == '$' && + (str[1] == 'a' || str[1] == 'd' || str[1] == 't' || str[1] == 'x') && (str[2] == '\0' || str[2] == '.'); } -- cgit v1.2.3 From 959bbaf5b7a9cc5504b88e3a5b87a11937df6366 Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Sat, 11 Jun 2022 03:32:30 +0900 Subject: modpost: fix section mismatch check for exported init/exit sections commit 28438794aba47a27e922857d27b31b74e8559143 upstream. Since commit f02e8a6596b7 ("module: Sort exported symbols"), EXPORT_SYMBOL* is placed in the individual section ___ksymtab(_gpl)+ (3 leading underscores instead of 2). Since then, modpost cannot detect the bad combination of EXPORT_SYMBOL and __init/__exit. Fix the .fromsec field. Fixes: f02e8a6596b7 ("module: Sort exported symbols") Signed-off-by: Masahiro Yamada Reviewed-by: Nick Desaulniers Signed-off-by: Greg Kroah-Hartman --- scripts/mod/modpost.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'scripts/mod/modpost.c') diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index 79aef50ede17..e48742760fec 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -1119,7 +1119,7 @@ static const struct sectioncheck sectioncheck[] = { }, /* Do not export init/exit functions or data */ { - .fromsec = { "__ksymtab*", NULL }, + .fromsec = { "___ksymtab*", NULL }, .bad_tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL }, .mismatch = EXPORT_TO_INIT_EXIT, .symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL }, -- cgit v1.2.3