From a7b014b54c16cf60b4194ac9dde96d258de9054e Mon Sep 17 00:00:00 2001 From: Anton Ivanov Date: Fri, 13 Nov 2020 10:26:17 +0000 Subject: [PATCH] um: Remove use of asprinf in umid.c commit 97be7ceaf7fea68104824b6aa874cff235333ac1 upstream. asprintf is not compatible with the existing uml memory allocation mechanism. Its use on the "user" side of UML results in a corrupt slab state. Fixes: 0d4e5ac7e780 ("um: remove uses of variable length arrays") Cc: stable@vger.kernel.org Signed-off-by: Anton Ivanov Signed-off-by: Richard Weinberger Signed-off-by: Greg Kroah-Hartman --- arch/um/os-Linux/umid.c | 17 +++++------------ 1 file changed, 5 insertions(+), 12 deletions(-) diff --git a/arch/um/os-Linux/umid.c b/arch/um/os-Linux/umid.c index 44def53a11cd..ea5c60f4393e 100644 --- a/arch/um/os-Linux/umid.c +++ b/arch/um/os-Linux/umid.c @@ -137,20 +137,13 @@ static inline int is_umdir_used(char *dir) { char pid[sizeof("nnnnn\0")], *end, *file; int dead, fd, p, n, err; - size_t filelen; + size_t filelen = strlen(dir) + sizeof("/pid") + 1; - err = asprintf(&file, "%s/pid", dir); - if (err < 0) - return 0; + file = malloc(filelen); + if (!file) + return -ENOMEM; - filelen = strlen(file); - - n = snprintf(file, filelen, "%s/pid", dir); - if (n >= filelen) { - printk(UM_KERN_ERR "is_umdir_used - pid filename too long\n"); - err = -E2BIG; - goto out; - } + snprintf(file, filelen, "%s/pid", dir); dead = 0; fd = open(file, O_RDONLY);