From f981bf6b9db87e0732b46bfe92fdad4d363225e8 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Sat, 25 May 2024 05:13:41 -0700 Subject: parse_fdinfo: Don't advance pointer twice [BZ #31798] pidfd_getpid.c has /* Ignore invalid large values. */ if (INT_MULTIPLY_WRAPV (10, n, &n) || INT_ADD_WRAPV (n, *l++ - '0', &n)) return -1; For GCC older than GCC 7, INT_ADD_WRAPV(a, b, r) is defined as _GL_INT_OP_WRAPV (a, b, r, +, _GL_INT_ADD_RANGE_OVERFLOW) and *l++ - '0' is evaluated twice. Fix BZ #31798 by moving "l++" out of the if statement. Tested with GCC 6.4 and GCC 14.1. Signed-off-by: H.J. Lu Reviewed-by: Adhemerval Zanella --- sysdeps/unix/sysv/linux/pidfd_getpid.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/sysdeps/unix/sysv/linux/pidfd_getpid.c b/sysdeps/unix/sysv/linux/pidfd_getpid.c index ebcbe8fdf6..6967477fab 100644 --- a/sysdeps/unix/sysv/linux/pidfd_getpid.c +++ b/sysdeps/unix/sysv/linux/pidfd_getpid.c @@ -74,8 +74,10 @@ parse_fdinfo (const char *l, void *arg) /* Ignore invalid large values. */ if (INT_MULTIPLY_WRAPV (10, n, &n) - || INT_ADD_WRAPV (n, *l++ - '0', &n)) + || INT_ADD_WRAPV (n, *l - '0', &n)) return -1; + + l++; } /* -1 indicates that the process is terminated. */ -- cgit 1.4.1