From 5ae4e2c2c660269d87dd5bbac6f590f69d0c7d8c Mon Sep 17 00:00:00 2001 From: Brian Behlendorf Date: Thu, 26 Aug 2010 11:03:04 -0700 Subject: [PATCH] Fix stack vn_open() We should not put a 4k maxpathlen buffer on the stack, instead locate it to the heap. Even in user space we run ztest with 8K stacks to verify correctness Signed-off-by: Brian Behlendorf --- lib/libzpool/kernel.c | 23 +++++++++++++++++------ 1 file changed, 17 insertions(+), 6 deletions(-) diff --git a/lib/libzpool/kernel.c b/lib/libzpool/kernel.c index 4bd08cd..0559347 100644 --- a/lib/libzpool/kernel.c +++ b/lib/libzpool/kernel.c @@ -517,10 +517,12 @@ vn_open(char *path, int x1, int flags, int mode, vnode_t **vpp, int x2, int x3) int fd; vnode_t *vp; int old_umask; - char realpath[MAXPATHLEN]; + char *realpath; struct stat64 st; int err; + realpath = umem_alloc(MAXPATHLEN, UMEM_NOFAIL); + /* * If we're accessing a real disk from userland, we need to use * the character interface to avoid caching. This is particularly @@ -534,11 +536,16 @@ vn_open(char *path, int x1, int flags, int mode, vnode_t **vpp, int x2, int x3) if (strncmp(path, "/dev/", 5) == 0) { char *dsk; fd = open64(path, O_RDONLY); - if (fd == -1) - return (errno); + if (fd == -1) { + err = errno; + free(realpath); + return (err); + } if (fstat64(fd, &st) == -1) { + err = errno; close(fd); - return (errno); + free(realpath); + return (err); } close(fd); (void) sprintf(realpath, "%s", path); @@ -548,8 +555,11 @@ vn_open(char *path, int x1, int flags, int mode, vnode_t **vpp, int x2, int x3) dsk + 1); } else { (void) sprintf(realpath, "%s", path); - if (!(flags & FCREAT) && stat64(realpath, &st) == -1) - return (errno); + if (!(flags & FCREAT) && stat64(realpath, &st) == -1) { + err = errno; + free(realpath); + return (err); + } } if (flags & FCREAT) @@ -560,6 +570,7 @@ vn_open(char *path, int x1, int flags, int mode, vnode_t **vpp, int x2, int x3) * FREAD and FWRITE to the corresponding O_RDONLY, O_WRONLY, and O_RDWR. */ fd = open64(realpath, flags - FREAD, mode); + free(realpath); if (flags & FCREAT) (void) umask(old_umask); -- 1.8.3.1