diff options
author | Alexander Graf <agraf@suse.de> | 2011-11-21 12:04:07 +0100 |
---|---|---|
committer | Riku Voipio <riku.voipio@linaro.org> | 2012-02-02 17:51:20 +0200 |
commit | 962b289ef35087fcd8764e4e29808d8ac90157f7 (patch) | |
tree | 01641e19658a15ae9861350a18273b580c0faccc /linux-user | |
parent | 583359a68922fb91b793a5ad3a2dd4536bf9b99e (diff) | |
download | qemu-962b289ef35087fcd8764e4e29808d8ac90157f7.zip qemu-962b289ef35087fcd8764e4e29808d8ac90157f7.tar.gz qemu-962b289ef35087fcd8764e4e29808d8ac90157f7.tar.bz2 |
linux-user: fix QEMU_STRACE=1 segfault
While debugging some issues with QEMU_STRACE I stumbled over segmentation
faults that were pretty reproducible. Turns out we tried to treat a
normal return value as errno, resulting in an access over array boundaries
for the resolution.
Fix this by allowing failure to resolve invalid errnos into strings.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>
Diffstat (limited to 'linux-user')
-rw-r--r-- | linux-user/strace.c | 18 | ||||
-rw-r--r-- | linux-user/syscall.c | 3 |
2 files changed, 17 insertions, 4 deletions
diff --git a/linux-user/strace.c b/linux-user/strace.c index 90027a1..269481e 100644 --- a/linux-user/strace.c +++ b/linux-user/strace.c @@ -284,8 +284,13 @@ print_ipc(const struct syscallname *name, static void print_syscall_ret_addr(const struct syscallname *name, abi_long ret) { -if( ret == -1 ) { - gemu_log(" = -1 errno=%d (%s)\n", errno, target_strerror(errno)); + char *errstr = NULL; + + if (ret == -1) { + errstr = target_strerror(errno); + } + if ((ret == -1) && errstr) { + gemu_log(" = -1 errno=%d (%s)\n", errno, errstr); } else { gemu_log(" = 0x" TARGET_ABI_FMT_lx "\n", ret); } @@ -1515,14 +1520,19 @@ void print_syscall_ret(int num, abi_long ret) { int i; + char *errstr = NULL; for(i=0;i<nsyscalls;i++) if( scnames[i].nr == num ) { if( scnames[i].result != NULL ) { scnames[i].result(&scnames[i],ret); } else { - if( ret < 0 ) { - gemu_log(" = -1 errno=" TARGET_ABI_FMT_ld " (%s)\n", -ret, target_strerror(-ret)); + if (ret < 0) { + errstr = target_strerror(-ret); + } + if (errstr) { + gemu_log(" = -1 errno=" TARGET_ABI_FMT_ld " (%s)\n", + -ret, errstr); } else { gemu_log(" = " TARGET_ABI_FMT_ld "\n", ret); } diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 15b8b22..29d92c4 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -731,6 +731,9 @@ static inline int is_error(abi_long ret) char *target_strerror(int err) { + if ((err >= ERRNO_TABLE_SIZE) || (err < 0)) { + return NULL; + } return strerror(target_to_host_errno(err)); } |