| Message ID | 20240721090817.120888-3-uwu@dram.page (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | linux-user: Fix handling when AT_EXECFD is 0 | expand |
On 7/21/24 19:08, Vivian Wang wrote: > It's possible for AT_EXECFD to end up with a valid value of 0. Check > errno when using qemu_getauxval instead of return value to handle this > case. > > Not handling this case leads to a confusing condition where the > executable ends up as fd 0, i.e. stdin. > > Signed-off-by: Vivian Wang <uwu@dram.page> > Fixes: 0b959cf5e4cc ("linux-user: Use qemu_getauxval for AT_EXECFD") > Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2448 > --- > linux-user/main.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/linux-user/main.c b/linux-user/main.c > index 7d3cf45fa9..8143a0d4b0 100644 > --- a/linux-user/main.c > +++ b/linux-user/main.c > @@ -755,8 +755,9 @@ int main(int argc, char **argv, char **envp) > /* > * Manage binfmt-misc open-binary flag > */ > + errno = 0; > execfd = qemu_getauxval(AT_EXECFD); > - if (execfd == 0) { > + if (errno != 0) { > execfd = open(exec_path, O_RDONLY); > if (execfd < 0) { > printf("Error while loading %s: %s\n", exec_path, strerror(errno)); Reviewed-by: Richard Henderson <richard.henderson@linaro.org> r~
diff --git a/linux-user/main.c b/linux-user/main.c index 7d3cf45fa9..8143a0d4b0 100644 --- a/linux-user/main.c +++ b/linux-user/main.c @@ -755,8 +755,9 @@ int main(int argc, char **argv, char **envp) /* * Manage binfmt-misc open-binary flag */ + errno = 0; execfd = qemu_getauxval(AT_EXECFD); - if (execfd == 0) { + if (errno != 0) { execfd = open(exec_path, O_RDONLY); if (execfd < 0) { printf("Error while loading %s: %s\n", exec_path, strerror(errno));
It's possible for AT_EXECFD to end up with a valid value of 0. Check errno when using qemu_getauxval instead of return value to handle this case. Not handling this case leads to a confusing condition where the executable ends up as fd 0, i.e. stdin. Signed-off-by: Vivian Wang <uwu@dram.page> Fixes: 0b959cf5e4cc ("linux-user: Use qemu_getauxval for AT_EXECFD") Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2448 --- linux-user/main.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)