From 836b2fe544a5e9b5ce116622cb36fba33838c6fd Mon Sep 17 00:00:00 2001 From: Eduard Zingerman Date: Fri, 4 Sep 2026 01:33:23 -0700 Subject: selftests/bpf: Check that JMP32 pointer vs zero jumps are not predicted Add jmp32_ptr_vs_zero_jne: the fall-through of the 32-bit compare, which the verifier used to skip, contains an out of bounds map value access, hence w/o the previous patch the program is accepted. See previous patch for detailed description. Reported-by: Nicholas Carlini Suggested-by: Nicholas Carlini Signed-off-by: Eduard Zingerman Link: https://lore.kernel.org/bpf/20260904083325.2083493-6-eddyz87@gmail.com Signed-off-by: Kumar Kartikeya Dwivedi --- fs/proc/util.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) create mode 100644 fs/proc/util.c (limited to 'fs/proc/util.c') diff --git a/fs/proc/util.c b/fs/proc/util.c new file mode 100644 index 000000000..98f8adc17 --- /dev/null +++ b/fs/proc/util.c @@ -0,0 +1,24 @@ +#include +#include "internal.h" + +unsigned name_to_int(const struct qstr *qstr) +{ + const char *name = qstr->name; + int len = qstr->len; + unsigned n = 0; + + if (len > 1 && *name == '0') + goto out; + do { + unsigned c = *name++ - '0'; + if (c > 9) + goto out; + if (n >= (~0U-9)/10) + goto out; + n *= 10; + n += c; + } while (--len > 0); + return n; +out: + return ~0U; +} -- cgit v1.3.1