diff options
author | Helge Deller <deller@gmx.de> | 2023-08-03 23:44:47 +0200 |
---|---|---|
committer | Richard Henderson <richard.henderson@linaro.org> | 2023-08-09 09:31:30 -0700 |
commit | b8002058c45a50d893c51cf62ec96c70128fc1eb (patch) | |
tree | 6574e6289014c21dad50672cc4e0e99465084af5 /linux-user/syscall.c | |
parent | 47d1e982318a0d97c557ce349ea9e2b601554055 (diff) | |
download | qemu-b8002058c45a50d893c51cf62ec96c70128fc1eb.zip qemu-b8002058c45a50d893c51cf62ec96c70128fc1eb.tar.gz qemu-b8002058c45a50d893c51cf62ec96c70128fc1eb.tar.bz2 |
linux-user: Fix openat() emulation to correctly detect accesses to /proc
In qemu we catch accesses to files like /proc/cpuinfo or /proc/net/route
and return to the guest contents which would be visible on a real system
(instead what the host would show).
This patch fixes a bug, where for example the accesses
cat /proc////cpuinfo
or
cd /proc && cat cpuinfo
will not be recognized by qemu and where qemu will wrongly show
the contents of the host's /proc/cpuinfo file.
Signed-off-by: Helge Deller <deller@gmx.de>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20230803214450.647040-2-deller@gmx.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Diffstat (limited to 'linux-user/syscall.c')
-rw-r--r-- | linux-user/syscall.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 12ebc70..9353268 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -8557,9 +8557,12 @@ static int open_hardware(CPUArchState *cpu_env, int fd) } #endif -int do_guest_openat(CPUArchState *cpu_env, int dirfd, const char *pathname, + +int do_guest_openat(CPUArchState *cpu_env, int dirfd, const char *fname, int flags, mode_t mode, bool safe) { + g_autofree char *proc_name = NULL; + const char *pathname; struct fake_open { const char *filename; int (*fill)(CPUArchState *cpu_env, int fd); @@ -8585,6 +8588,14 @@ int do_guest_openat(CPUArchState *cpu_env, int dirfd, const char *pathname, { NULL, NULL, NULL } }; + /* if this is a file from /proc/ filesystem, expand full name */ + proc_name = realpath(fname, NULL); + if (proc_name && strncmp(proc_name, "/proc/", 6) == 0) { + pathname = proc_name; + } else { + pathname = fname; + } + if (is_proc_myself(pathname, "exe")) { if (safe) { return safe_openat(dirfd, exec_path, flags, mode); |