From be893b4ffd862a352fad9f2fe57cd7a00276ce6f Mon Sep 17 00:00:00 2001 From: kib Date: Sun, 6 Jan 2019 23:59:04 +0000 Subject: [PATCH] Clamp tuklib_physmem() return value to SIZE_T_MAX. On 32bit platforms it is possible to have (much) more physical RAM than is mappable into single address space. In this case liblzma scales the value into a request to mmap more address space than it is theoretically possible. Reported and tested by: pho Reviewed by: delphij Discussed with: emaste Sponsored by: The FreeBSD Foundation MFC after: 1 week --- contrib/xz/src/common/tuklib_physmem.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/contrib/xz/src/common/tuklib_physmem.c b/contrib/xz/src/common/tuklib_physmem.c index 4053ad006a64..01f6d1779510 100644 --- a/contrib/xz/src/common/tuklib_physmem.c +++ b/contrib/xz/src/common/tuklib_physmem.c @@ -45,6 +45,7 @@ # include #elif defined(TUKLIB_PHYSMEM_SYSCONF) +# include # include #elif defined(TUKLIB_PHYSMEM_SYSCTL) @@ -145,13 +146,16 @@ tuklib_physmem(void) #elif defined(TUKLIB_PHYSMEM_SYSCONF) const long pagesize = sysconf(_SC_PAGESIZE); const long pages = sysconf(_SC_PHYS_PAGES); - if (pagesize != -1 && pages != -1) + if (pagesize != -1 && pages != -1) { // According to docs, pagesize * pages can overflow. // Simple case is 32-bit box with 4 GiB or more RAM, // which may report exactly 4 GiB of RAM, and "long" // being 32-bit will overflow. Casting to uint64_t // hopefully avoids overflows in the near future. ret = (uint64_t)pagesize * (uint64_t)pages; + if (ret > SIZE_T_MAX) + ret = SIZE_T_MAX; + } #elif defined(TUKLIB_PHYSMEM_SYSCTL) int name[2] = {